Heat Pipe Reliability Test
Heat pipe technology is a heat transfer element called "heat pipe" invented by G.M. rover of Los Alamos National Laboratory in 1963, which makes full use of the principle of heat conduction and the rapid heat transfer properties of the refrigeration medium, and transfers the heat of the heating object quickly to the heat source through the heat pipe. Its thermal conductivity exceeds that of any known metal. Heat pipe technology has been widely used in aerospace, military and other industries, since it has been introduced into the radiator manufacturing industry, making people change the design idea of the traditional radiator, and get rid of the single heat dissipation mode that simply relies on high air volume motor to obtain better heat dissipation effect. The use of heat pipe technology makes the radiator even if the use of low speed, low air volume motor, can also get satisfactory results, so that the noise problem plagued by air cooling heat has been well solved, opening up a new world in the heat dissipation industry.
Heat pipe reliability test conditions:
High temperature stress screening test: 150℃/24 hours
Temperature cycling test:
120℃(10min)←→-30℃(10min), Ramp: 0.5℃, 10cycles 125℃(60min)←→-40℃(60min), Ramp: 2.75℃, 10cycles
Thermal shock test:
120℃(2min)←→-30℃(2min), 250 cycles
125℃(5min)←→-40℃(5min), 250 cycles
100℃(5min)←→-50℃(5min), 2000 cycles(check once after 200 cycles)
High temperature and high humidity test:
85℃/85%R.H./1000 hours
Accelerated aging test:
110℃/85%RH/264h
Other heat pipe test items:
Salt spray test, strength (blasting) test, leakage rate test, vibration test, random vibration test, mechanical shock test, helium combustion test, performance test, wind tunnel test
Multi-touch Panel Testing
When the human body is close to the touchpad, the capacitance value between the sensing pad and the ground will change (general pf level). Capacitive touch pad (also known as: Surface capacitive) is through the use of the sensor detected by the change of capacitance value by calculating microprocessor, filtering interference and finally determining whether there is a human body close to achieve the key function. Compared with the traditional mechanical keys, the advantage is that there is no mechanical damage, and non-metals such as glass, acrylic, plastic can be used as the operating panel isolation, making the appearance of the product more atmospheric. In contrast, it can also realize the sliding operation that is difficult to achieve with traditional mechanical keys, so that the human-machine interface is more in line with the intuitive operation of people.
The outermost layer of the capacitive touch panel is a thin silicon dioxide hardening processing layer, and its hardness reaches 7; The second layer is ITO(conductive coating), through the conductive layer on the front of the average distribution of low-voltage conduction current, to establish a uniform electric field on the glass surface, when the finger touches the surface of the touch panel, it will absorb a small amount of current from the contact point, resulting in a voltage drop of the corner electrode, the use of sensing the weak current of the human body to achieve the purpose of touch; The function of the bottom layer of ITO is to shield electromagnetic waves, so that the touch panel can work in a good environment without interference. While the projective capacitive, which is the touch mode used by the famous Apple iPhone and Windows 7, has the feature of supporting multi-touch, which can shorten the user's learning time, just use the finger belly touch panel to avoid the use of stylus, and has higher light transmission and more power saving, more scratch resistance than resistive type (hardness up to 7H or more), greatly increase the service life without correction...
Touch technology can be divided into four kinds according to the principle of sensing, including resistive, capacitive, surface acoustic wave and optics. And capacitive can also be divided into surface capacitive and projected capacitive two kinds.
Touch technology applications:
Industrial applications (automatic processing machines, measuring instruments, centralized monitoring and control)
Commercial applications (ticketing systems, POS, ATMs, vending machines, stored value machines)
Life applications (cell phones, satellite positioning GPS, UMPC, small laptop)
Education and entertainment (e-books, portable game consoles, jukeboxes, electronic dictionaries)
Comparison of touch panel light transmission rate: resistive (85%), capacitive (93%)
Multi-touch panel test conditions:
Operating temperature range: -20℃～70℃/20%～85%RH
Storage temperature range: -50℃～85℃/10%～90%RH
High temperature test: 70℃/240, 500 hours, 80℃/240, 1000 hours, 85℃/1000 hours, 100℃/240 hours
Low temperature test: -20℃/240 hours, -40℃/240, 500 hours, -40℃/1000 hours
High temperature and high humidity test: 60℃/90%RH/240hours, 60℃/95%RH/1000hours 70℃/80%RH/500hours, 70℃/90%RH/240,500,1000hours, 70℃/95%RH/500hours 85℃/85%RH/1000hours, 85℃/90%RH/1000hours
Boiling test: 100℃/100%RH/100 minutes
Temperature shock - high and low temperature: (Temperature shock test is not equivalent to temperature cycling test )
-30℃←→80℃, 500cycles
-40℃(30min)←→70(30min)℃, 10cycles
-40℃←→70℃, 50, 100cycles
-40℃(30min)←→110℃(30min), 100cycles
-40℃(30min)←→80℃(30min), 10, 100cycles
-40℃(30min)←→90℃(30min), 100cycles
Thermal Shock Test - Liquid Type: -40℃←→90℃, 2cycles
Cold and thermal shock test-over room temperature: -30℃(30min)→R.T. (5min)→80℃(30min), 20cycles
Service life: 1,000,000 times, 2,000,000 times, 35,000,000 times, 225,000,000 times, 300,000,000 times
Hardness test: greater than hardness level 7 (ASTM D 3363, JIS 5400)
Impact Test: With more than 5kg of force, strike the panel on the most vulnerable area and the center of the panel respectively.
Pin(Tail) Pulling Test: 5 or 10kg downward pulling.
Pin Folding Test：135¢angle, left and right back and forth for 10 times.
Impact resistance test: 11φ/5.5g copper ball dropped at 1.8m height on the center surface of 1m object, 3ψ/9g stainless steel ball dropped at 30cm height.
Writing durability: 100,000 characters or more (width R0.8mm, pressure 250g)
Touch durability: 1,000,000, 10,000,000, 160,000,000, 200,000,000 times or more (width R8 mm, hardness 60°, pressure 250g, 2 times per second)
Test equipment:
Test equipment
Test Requirements and Conditions
Temperature & humidity test chamber
Equipment features: high-strength, high-reliability structural design - to ensure the high reliability of the equipment; working room materials for the SUS304 stainless steel - corrosion resistance, strong anti-fatigue thermal function, long service life; high-density polyurethane foam insulation materials - to ensure that the heat loss is reduced to a little; the surface of the plastic spraying treatment - to ensure that the equipment's lasting corrosion-resistant function and the appearance of the life; high-strength temperature-resistant Silicone rubber sealing strip - to ensure the high sealing of the equipment door.
High temperature & high humidity test chamber
High temperature and high humidity test chamber series, passed the CE certification, offer 34L, 64L, 100L, 180L, 340L, 600L, 1000L, 1500L and other volume models to meet the needs of different customers. In design, they use environment-friendly refrigerant and high-performance refrigeration system, parts and components are used in the international famous brand.
Two-Zone(Basket Type)
Thermal shock test chamber
Applicable to the assessment of products (the whole machine), parts and components, etc. to withstand rapid changes in temperature. Thermal shock test chambers can understand the impact of the test sample once or repeatedly due to temperature changes. The main parameters affecting the temperature change test are the high and low temperature values of the temperature change range, the retention time of the sample at high and low temperature, and the number of test cycles.
Three-zone (Ventilation Type)
Thermal shock test chamber
TS series thermal shock test chambers have complete equipment specifications - two-zone(basket type), three-zone (ventilation type) and horizontal movement type are available for users to choose, fully meeting the various requirements of different users; The equipment can also provide standard high and low temperature test function to achieve the compatibility of temperature shock and high and low temperature test; high strength, high reliability of the structure design - ensure the high reliability of the equipment.
UV aging tester testing equipment
The structure of the test chamber is made of corrosion-resistant metal materials, including 8 fluorescent ultraviolet lamps, a water tray, a test sample holder, and temperature and time control systems and indicators.
2. The lamp power is 40W and the lamp length is 1200mm. The range of the uniform working area of the test box is 900 × 210mm.
3. The lights are installed in four rows, divided into two rows. The tubes of each row of lights are installed in parallel, and the center distance of the lights is 70mm.
4. The test sample is fixedly installed at a position 50mm away from the surface of the lamp surface. The test sample and its bracket form the inner wall of the box, and their backs are exposed to cooling air at room temperature due to the temperature difference between the test sample and the air inside the box. To create stable condensation conditions on the surface of the test sample during the condensation stage, the test chamber should generate natural air convection through the outer wall of the chamber and the channel of the test sample at the bottom.
5. Water vapor is generated by a water tray located at the bottom of the heating box, with a water depth not exceeding 25mm, and equipped with an automatic water supply controller. The water tray should be regularly cleaned to prevent the formation of scale.
6. The temperature of the test chamber is measured by a sensor fixed on a black aluminum plate (blackboard) with a width of 75mm, height of 100mm, and thickness of 2.5mm. The blackboard should be placed in the central area of the exposure test, and the measurement range of the thermometer is 30-80 ℃ with a tolerance of ± 1 ℃. The control of lighting and condensation stages should be carried out separately, and the condensation stage is controlled by the heating water temperature.
7. The test chamber should be placed in a test room with a temperature of 15-35 ℃, 300mm away from the wall, and should prevent the influence of other heat sources. The air in the test room should not circulate strongly to avoid affecting the lighting and condensation conditions.
Dear customer:
Hello, our company is a high-quality development team with strong technical strength, providing high-quality products, complete solutions, and excellent technical services to our customers. The main products include walk-in constant temperature and humidity testing chambers, UV accelerated aging testing machines, rapid temperature change testing chambers, walk-in environmental testing chambers, UV aging testers, constant temperature and humidity chambers, etc. Our company adheres to the principle of building a business with integrity, maintaining quality, and striving for progress. With a more determined pace, we continuously climb new heights and contribute to the national automation industry. We welcome new and old customers to confidently choose the products they like. We will serve you wholeheartedly!
Bicycle Lamp Reliability Test
Bicycles are in the social environment of high oil prices and environmental protection, with environmental protection, fitness, slow living... Such as multi-functional recreational sports equipment, and bicycle lights are an indispensable and important part of bicycle night riding, if the purchase of low-cost and not after reliability test of bicycle lights, riding at night or through the tunnel failure, not only for the rider has a serious threat to life safety, For driving, collision accidents can occur because the driver cannot see the cyclist, so it is important to have bicycle lights that pass the reliability test.
Reasons for bicycle lamp failure:
a. Deformation, embrittlement and fading of lamp shell caused by high temperature of lamp
b. yellowing and embrittlement of lamp shell caused by outdoor ultraviolet exposure
c. Riding up and down the hill due to high and low temperature changes in the environment caused by lamp failure
d. Abnormal power consumption of car lights
e. Lights fail after a long time of rain
f. Hot failure occurs when the lights are lit for a long time
g. During riding, the lamp fixture drags loose, causing the lamp to fall
h. Lamp circuit failure caused by road vibration and slope
Bicycle lamp test classification:
Environmental test, mechanical test, radiation test, electrical test
Initial characteristic test:
Take any 30, light the lamp with DC power supply according to the rated voltage, after the characteristics are stable, measure the distance between the current and the optical center, less than 10 defective products are qualified, more than 22 are unqualified, if the number of defective products is between 11 and 22, another 100 samples are collected for testing, and the number of defective products under the original inspection is qualified when the number is less than 22. If the number exceeds 22, it is disqualified.
Life test: 10 bulbs passed the initial characteristic test, and 8 of them met the requirements.
Bicycle test speed: simulated 15 km/h environment
High temperature test (temperature test) : 80℃, 85℃, 90℃
Low temperature test: -20℃
Temperature cycle: 50℃(60min)→ normal temperature (30min)→20(60min)→ normal temperature (30min), 2cycle
Wet heat test: 30℃/95%R.H/48 hours
Stress screening test: High temperature: 85℃←→ Low temperature: -25℃, dwell time: 30min, cycle: 5cycles, power on, time: ≧24h
Shell salt spray test: 20℃/15% salt concentration/spray for 6 hours, determination method: the surface of the shell should not occur obvious rust
Waterproof test:
Description: The IPX rating of rainproof lamps needs to be at least IPX3 or above
IPX3(Water resistance) : Drop 10 liters of water vertically from a height of 200CM at 60˚ (test time: 10 minutes)
IPX4(anti-water, anti-splash) : 10 liters of water drops from 30 ~ 50CM in any direction (test time: 10 minutes)
IPX5:3m 12.5L of water from any direction [weak water](test time: 3 minutes)
IPX6:3m Strong spray 30 liters from any direction [strong water, pressure: 100KPa](test time: 3 minutes)
IPX7(Life waterproof) : It can be used for 30 minutes under 1m in water
Vibration test: vibration number 11.7 ~ 20Hz/amplitude: 11 ~ 4mm/ time: up and down 2h, about 2h, 2h before and after 2h/acceleration 4 ~ 5g
Drop test: 1 meter (hand drop), 2 meters (bicycle fall, fall from the frame)/ concrete floor/four times/four sides
Impact test: 10mm flat wooden platform/Distance: 1 m/diameter 20mm mass 36g steel ball free fall/top surface and side once
Low temperature impact: When the sample is cold to -5℃, maintain this temperature for three hours and then carry out the impact test
Irradiation test: long time irradiation brightness test, low voltage irradiation test, light brightness, light color
Bicycle lamp noun sorting:
Natural Convection Test (No Wind Circulation Temperature Test) and Specification
Home entertainment audio-visual equipment and automotive electronics are one of the key products of many manufacturers, and the product in the development process must simulate the adaptability of the product to temperature and electronic characteristics at different temperatures. However, when the general oven or constant temperature and humidity test chamber is used to simulate the temperature environment, both the oven and constant temperature and humidity test chamber have a test area equipped with a circulating fan, so there will be wind speed problems in the test area. During the test, the temperature uniformity is balanced by rotating the circulating fan. Although the temperature uniformity of the test area can be achieved through the wind circulation, the heat of the product to be tested will also be taken away by the circulating air, which will be significantly inconsistent with the actual product in the wind-free use environment (such as the living room, indoor). Because of the relationship of wind circulation, the temperature difference of the product to be tested will be nearly 10 ° C, in order to simulate the actual use of environmental conditions, many people will misunderstand that only the test machine can produce temperature (such as: oven, constant temperature and humidity test chamber) can carry out natural convection test, in fact, this is not the case. In the specification, there are special requirements for wind speed, and a test environment without wind speed is required. Through the natural convection test equipment (no forced wind circulation test), the temperature environment without fan is generated (natural convection test), and then the test integration test is carried out to detect the temperature of the product under test. This solution can be applied to the actual ambient temperature test of household related electronic products or confined Spaces (such as: Large LCD TV, car cockpit, car electronics, laptop, desktop computer, game console, stereo... Etc.).
The difference of the test environment with or without wind circulation for the test of the product to be tested:
If the product to be tested is not energized, the product to be tested will not heat itself, its heat source only absorbs the air heat in the test furnace, and if the product to be tested is energized and heated, the wind circulation in the test furnace will take away the heat of the product to be tested. Every 1 meter increase in wind speed, its heat will be reduced by about 10%. Suppose to simulate the temperature characteristics of electronic products in an indoor environment without air conditioning, if an oven or a constant temperature and humidity test chamber is used to simulate 35 ° C, although the environment in the test area can be controlled within 35 ° C through electric heating and freezing, the wind circulation of the oven and the constant temperature and humidity test chamber will take away the heat of the product to be tested, making the actual temperature of the product to be tested lower than the temperature in the real state of no wind. Therefore, it is necessary to use a natural convection testing machine without wind speed to effectively simulate the actual windless environment (such as: indoor, non-starting car cockpit, instrument chassis, outdoor waterproof box... Such environment).
Indoor environment without wind circulation and solar radiant heat irradiation:
Through the natural convection tester, simulate the client's actual use of the real air conditioning convection environment, hot spot analysis and heat dissipation characteristics of the product evaluation, such as the LCD TV in the photo not only to consider its own heat dissipation, but also to evaluate the impact of thermal radiation outside the window, thermal radiation for the product may produce additional radiant heat above 35 ° C.
Comparison table of wind speed and IC product to be tested:
When the ambient wind speed is faster, the IC surface temperature will also take away the IC surface heat due to the wind cycle, resulting in faster wind speed and lower temperature, when the wind speed is 0, the temperature is 100℃, but when the wind speed reaches 5m/s, the IC surface temperature has been below 80℃.
Unforced air circulation test:
According to the specification requirements of IEC60068-2-2, in the high temperature test process, it is necessary to carry out the test conditions without forced air circulation, the test process needs to be maintained under the wind-free circulation component, and the high temperature test is carried out in the test furnace, so the test cannot be carried out through the constant temperature and humidity test chamber or oven, and the natural convection tester can be used to simulate the free air conditions.
Description of test conditions:
Test specification for unforced air circulation: IEC-68-2-2, GB2423.2, GB2423.2-89 3.3.1
Unforced air circulation test: The test condition of unforced air circulation can simulate the free air condition well
GB2423.2-89 3.1.1:
When measuring under free air conditions, when the temperature of the test sample is stable, the temperature of the most hot spot on the surface is more than 5℃ higher than the temperature of the surrounding large device, it is a heat dissipation test sample, otherwise it is a non-heat dissipation test sample.
GB2423.2-8 10(Test heat dissipation test sample temperature gradient test) :
A standard test procedure is provided to determine the adaptability of thermal electronic products (including components, equipment level other products) to use at high temperatures.
Test requirements:
a. Testing machine without forced air circulation (equipped with a fan or blower)
b. Single test sample
c. The heating rate is not greater than 1℃/min
d. After the temperature of the test sample reaches stability, the test sample is energized or the home electrical load is carried out to detect the electrical performance
Natural convection test chamber features:
1. Can evaluate the heat output of the product to be tested after power, to provide the best distribution uniformity;
2. Combined with digital data collector, effectively measure the relevant temperature information of the product to be tested for synchronous multi-track analysis;
3. Record the information of more than 20 rails (synchronous record the temperature distribution inside the test furnace, multi-track temperature of the product to be tested, average temperature... Etc.).
4. The controller can directly display the multi-track temperature record value and record curve; Multi-track test curves can be stored on a USB drive via the controller;
5. The curve analysis software can intuitively display the multi-track temperature curve and output EXCEL reports, and the controller has three kinds of display [Complex English];
6. Multi-type thermocouple temperature sensor selection (B, E, J, K, N, R, S, T);
7. Scalable to increase heating rate & control stability planning.
Structural characteristics of temperature and humidity control box
The full name of the temperature and humidity control chamber is "Constant Temperature and Humidity Test Chamber", which is an essential testing equipment in aviation, automotive, home appliances, scientific research and other fields. It is used to test and determine the parameters and performance of electrical, electronic and other products and materials after high temperature, low temperature, humidity and heat or constant temperature environment changes. It can be mainly divided into "desktop" and "vertical" according to testing requirements and standards, with the difference being the temperature and humidity that can be achieved. The vertical type can be used for low temperature and drying below room temperature, while the desktop type can only be used for temperature and high humidity above room temperature.
Suitable for various small electrical appliances, instruments, materials, and components for wet heat testing, it is also suitable for conducting aging tests. This test chamber adopts the most reasonable structure and stable and reliable control method currently available, making it aesthetically pleasing, easy to operate, safe, and with high precision in temperature and humidity control. It is an ideal equipment for conducting constant temperature and humidity tests.
1) The test box body is in the form of an integral structure, with the refrigeration system located at the lower rear of the box and the control system located at the upper part of the test box.
(2) Inside the air duct interlayer at one end of the studio, there are devices such as heaters, refrigeration evaporators, and fan blades distributed; On the left side of the test box, there is a Ø 50 cable hole, and the test box is a single door (stainless steel embedded door handle)
(3) The double-layer high temperature and anti-aging silicone rubber seal can effectively ensure the temperature loss of the test chamber
(4) There are observation windows, frost prevention devices, and switchable lighting fixtures on the box door. The observation window adopts multi-layer hollow tempered glass, and the inner adhesive sheet conductive film is heated and defrosted. The lighting fixtures use imported brand Philips lamps, which can effectively observe the experimental changes in the studio from all angles.
Dear customer:
Hello, our company is a high-quality development team with strong technical strength, providing high-quality products, complete solutions, and excellent technical services to our customers. The main products include walk-in constant temperature and humidity testing chambers, UV accelerated aging testing machines, rapid temperature change testing chambers, walk-in environmental testing chambers, UV aging testers, constant temperature and humidity chambers, etc. Our company adheres to the principle of building a business with integrity, maintaining quality, and striving for progress. With a more determined pace, we continuously climb new heights and contribute to the national automation industry. We welcome new and old customers to confidently choose the products they like. We will serve you wholeheartedly!
Temperature control of solar simulation irradiation test chamber
The test chamber uses an artificial light source combined with a G7 OUTDOOR filter to adjust the system light source to meet the requirements of IEC61646 for solar simulators by simulating the radiation in natural sunlight. The above system light source is used to conduct the IEC61646 photoaging test on the solar cell module, and the temperature on the back of the module needs to be constantly controlled between 50 ± 10℃during the test. Can automatically monitor temperature; Configure a radiometer to control the irradiance of light, ensuring it remains stable at a specified level, while also controlling the testing time.
During the ultraviolet light cycle period in the solar simulation irradiation test chamber, photochemical reactions are usually not sensitive to temperature. But the rate of any subsequent reaction depends on the temperature. The rate of these reactions accelerates with increasing temperature. Therefore, controlling the temperature during UV exposure is crucial. In addition, it is necessary to ensure that the temperature of the accelerated aging test is consistent with the highest temperature at which the material is directly exposed to sunlight. In the solar simulation irradiation test chamber, the UV exposure temperature can be set at any temperature between 50 ℃ and 80 ℃ based on the illuminance and ambient temperature. The UV exposure temperature is adjusted by a sensitive temperature controller and blower system to achieve excellent uniformity in the temperature of this test chamber.
Dear customer:
Hello, our company is a high-quality development team with strong technical strength, providing high-quality products, complete solutions, and excellent technical services to our customers. The main products include walk-in constant temperature and humidity testing chambers, UV accelerated aging testing machines, rapid temperature change testing chambers, walk-in environmental testing chambers, UV aging testers, constant temperature and humidity chambers, etc. Our company adheres to the principle of building a business with integrity, maintaining quality, and striving for progress. With a more determined pace, we continuously climb new heights and contribute to the national automation industry. We welcome new and old customers to confidently choose the products they like. We will serve you wholeheartedly!
PCB Performs Accelerated Tests of Ion Migration and CAF Through HAST
PCB In order to ensure its long-term use quality and reliability, need to carry out SIR (Surface Insulation Resistance) surface insulation resistance test, through its test method to find out whether the PCB will occur MIG(ion migration) and CAF(glass fiber anode leakage) phenomenon, Ion migration is performed in a humidified state (e.g. 85℃/85%R.H.) with a constant bias (e.g. 50V), the ionized metal moves between the opposite electrodes (cathode to anode growth), the relative electrode is reduced to the original metal and precipitated dendritic metal phenomenon, often resulting in short circuit, ion migration is very fragile, the current generated at the moment of power will make the ion migration itself dissolves and disappears, MIG and CAF commonly used norms: IPC-TM-650-2.6.14., IPC-SF-G18, IPC-9691A, IPC-650-2.6.25, MIL-F-14256D, ISO 9455-17, JIS Z 3284, JIS Z 3197... But its test time is often 1000h, 2000h, for the cyclical products slow emergency, and HAST is a test method is also the name of the equipment, HAST is to improve environmental stress (temperature, humidity, pressure), in the unsaturated humidity environment (humidity: 85%R.H.) Speed up the test process to shorten the test time, used to assess PCB pressing, insulation resistance, and the moisture absorption effect of related materials, shorten the test time of high temperature and humidity (85℃/ 85%R.H. /1000h→110℃/ 85%R.H. /264h), the main reference specifications of PCB HAST test are: JESD22-A110-B, JCA-ET-01, JCA-ET-08.
HAST Accelerated Life Mode:
★ Increase temperature (110℃, 120℃, 130℃)
★ Maintain high humidity (85%R.H.)
Taken the pressure (110 ℃ / / 0.12 MPa, 120 ℃, 85% / 85% / 85% 0.17 MPa, 130 ℃ / / 0.23 MPa)
★ Extra bias (DC)
HAST test conditions for PCB:
1. Jca-et-08:110, 120, 130 ℃/85%R.H. /5 ~ 100V
2. High TG epoxy multilayer board: 120℃/85%R.H./100V, 800 hours
3. Low inductance multilayer board: 110℃/85% R.H./50V/300h
4. Multi-layer PCB wiring, material: 120℃/85% R.H/100V/ 800h
5. Low expansion coefficient & low surface roughness halogen-free insulation material: 130℃/ 85% R.H/12V/240h
6. Optically active covering film: 130℃/ 85% R.H/6V/100h
7. Heat hardening plate for COF film: 120℃/ 85% R.H/100V/100h
Lab Companion HAST High Acceleration Stress Test System (JESD22-A118/JESD22-A110)
The HAST independently developed by Macro Technology fully owns independent intellectual property rights, and the performance indicators can fully benchmark foreign brands. It can provide single-layer and double-layer models and two series of UHAST BHAST. It solves the problem of long-term dependence on imports of this equipment, long delivery time of imported equipment (up to 6 months) and high price. High Accelerated Stress Testing (HAST) combines high temperature, high humidity, high pressure, and time to measure the reliability of components with or without electrical bias. HAST testing accelerates the stress of more traditional testing in a controlled way. It is essentially a corrosion failure test. Corrosion-type failure is accelerated, and defects such as packaging seals, materials and joints are detected in a relatively short time.
Reliability of Ceramic Substrate
Ceramic PCB (Ceramic Substrate) refers to a special process plate where copper foil is directly bonded to the surface (single or double) of alumina (Al2O3) or aluminum nitride (AlN) ceramic substrate at high temperature. The ultra-thin composite substrate has excellent electrical insulation performance, high thermal conductivity, excellent soldering and high adhesion strength, and can be etched into a variety of graphics like PCB board, with great current carrying capacity. Therefore, the ceramic substrate has become the basic material of high-power electronic circuit structure technology and interconnect technology, which is suitable for products with high caloric value (high-brightness LED, solar energy), and its excellent weather resistance can be applied to harsh outdoor environments.
Main application products: high power LED carrier board, LED lights, LED street lights, solar inverter
Ceramic substrate features:
Structure: Excellent mechanical strength, low warping, thermal expansion coefficient close to silicon wafer (aluminum nitride), high hardness, good processability, high dimensional accuracy
Climate: Suitable for high temperature and humidity environment, high thermal conductivity, good heat resistance, corrosion and wear resistance, UV& yellowing resistance
Chemistry: Lead-free, non-toxic, good chemical stability
Electrical: high insulation resistance, easy metallization, circuit graphics and strong adhesion
Market: Abundant materials (clay, aluminum), easy to manufacture, low price
PCB material thermal characteristics comparison (conductivity) :
Glass fiber board (traditional PCB) : 0.5W/mK, aluminum substrate: 1~2.2W/mK, ceramic substrate: 24[alumina]~170[aluminum nitride]W/mK
Material heat transfer coefficient (unit W/mK) :
Resin: 0.5, alumina: 20-40, silicon carbide: 160, aluminum: 170, aluminum nitride: 220, copper: 380, diamond: 600
Ceramic substrate process classification:
According to the line ceramic substrate process is divided into: thin film, thick film, low temperature co-fired multi-layer ceramic (LTCC)
Thin Film Process (DPC) : Precise control of component circuit design (line width and film thickness)
Thick film process (Thick film) : to provide heat dissipation and weather conditions
Low temperature co-fired multilayer ceramic (HTCC) : The use of glass ceramics with low sintering temperature, low melting point, high conductivity of precious metal co-fired characteristics, multi-layer ceramic substrate) and assembly.
Low temperature co-fired multilayer ceramics (LTCC) : Stack several ceramic substrates and embed passive components and other ics
Thin film ceramic substrate process:
· Pretreatment → sputtering → photoresistance coating → exposure development → line plating → film removal
· Lamination → hot pressing → degreasing → substrate firing → circuit pattern formation → circuit firing
· Lamination → surface printed circuit pattern → hot pressing → degreasing → co-firing
· Printed circuit graphics → lamination → hot pressing → degreasing → co-firing
Ceramic substrate reliability test conditions:
Ceramic substrate high temperature operation: 85℃
Ceramic substrate low temperature operation: -40℃
Ceramic substrate cold and thermal shock:
1. 155℃(15min)←→-55℃(15min)/300cycle
2. 85 ℃ (30 min) please - - 40 ℃ (30 min)/RAMP: 10 min (12.5 ℃ / min) / 5 cycle
Ceramic substrate adhesion: Stick to the surface of the board with 3M#600 tape. After 30 seconds, tear quickly in a 90° direction with the surface of the board.
Ceramic substrate red ink experiment: Boil for one hour, impermeable
Test equipment:
1.High and low temperature humid heat test chamber
2. Three-box gas type cold and heat shock test chamber
Factors causing uneven temperature inside the high and low temperature humid heat test chamber
The high and low temperature damp heat test chamber is the main equipment in temperature and humidity environment testing, mainly used for conducting high and low temperature and humidity tests to evaluate the temperature and humidity resistance of products, so as to ensure that our products can work and operate normally under any environmental conditions. However, if the temperature uniformity exceeds the allowable deviation range during environmental testing in the high and low temperature damp heat test chamber, the data obtained from the test is unreliable and cannot be used as the ultimate tolerance for high and low temperature testing of materials or products. So what are the reasons that can cause temperature uniformity to exceed the allowable deviation range?
1. The differences in the test objects in the high and low temperature humid heat test chamber: If enough test samples that affect the overall internal heat convection are placed in the high and low temperature test chamber, it will inevitably affect the uniformity of the internal temperature to a certain extent, that is, the temperature uniformity. For example, if LED lighting products are placed, the products themselves emit light and heat, becoming a thermal load, which has a significant impact on temperature uniformity.
2. The design issues make it difficult to achieve a uniform symmetrical structure in the internal structure and space of the high and low temperature wet heat test chamber, and an asymmetric structure will inevitably lead to deviations in the uniformity of internal temperature. This aspect is mainly reflected in sheet metal design and processing, such as the design of air ducts, the placement of heating pipes, and the size of fan power. All of these will affect the temperature uniformity inside the box.
3. Due to the different structures of the inner wall of the high and low temperature humid heat test chamber, the temperature of the inner wall of the test chamber will also be uneven, which will affect the heat convection inside the working chamber and cause deviation in the internal temperature uniformity.
4. Due to the different heat transfer coefficients on the front, back, left, right, top, and bottom surfaces of the box wall in the studio, some have threading holes, detection holes, testing holes, etc., which cause local heat dissipation and transfer, resulting in uneven temperature distribution of the box body and uneven radiative convective heat transfer on the box wall, affecting temperature uniformity.
5. The sealing of the box and door is not strict, for example, the sealing strip is not customized and has seams, and the door leaks air, which affects the temperature uniformity of the workspace.
6. If the volume of the test object is too large, or if the position or method of placing the test object in the high and low temperature damp heat test chamber is inappropriate, it will obstruct the air convection inside and also cause significant temperature uniformity deviation. Placing the test product next to the air duct seriously affects the circulation of air, and of course, the uniformity of temperature will be greatly affected.
In summary, all of these points are the main culprits that affect the temperature uniformity inside the high and low temperature humid heat test chamber. We hope that everyone can investigate from these aspects one by one, which will surely solve your confusion and difficulties.
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Hello, our company is a high-quality development team with strong technical strength, providing high-quality products, complete solutions, and excellent technical services to our customers. The main products include walk-in constant temperature and humidity testing chambers, UV accelerated aging testing machines, rapid temperature change testing chambers, walk-in environmental testing chambers, UV aging testers, constant temperature and humidity chambers, etc. Our company adheres to the principle of building a business with integrity, maintaining quality, and striving for progress. With a more determined pace, we continuously climb new heights and contribute to the national automation industry. We welcome new and old customers to confidently choose the products they like. We will serve you wholeheartedly!
How to handle situations encountered during testing in a programmable constant temperature and humidity test chamber
The handling of interruptions in programmable constant temperature and humidity test chambers is clearly defined in GJB 150, which considers three types of interruptions: interruptions within tolerance range, interruptions under under under test conditions, and interruptions under over test conditions. Different situations have different handling methods. For interruptions within the tolerance range, when the test conditions during the interruption period do not exceed the allowable error range, the interruption time should be considered as a part of the total test time; For the interruption of under test conditions, when the test conditions are below the lower limit of allowable error, the predetermined test conditions should be reached again from the point below the test conditions, and the test should be resumed until the predetermined test cycle is completed; Rework the test sample. If the test conditions do not directly affect the interruption of the test conditions, and if the test sample fails in future tests, the test result should be considered invalid. In practical work, we adopt the method of retesting after repairing the test sample for interruptions caused by faults in the test sample; For test interruptions caused by experimental equipment reasons (such as sudden water or power outages, equipment failures, etc.), if the interruption time is not very long (within 2 hours), we usually handle it according to the under test conditions specified in GJB 150. If the time is too long, the test must be redone. The reason for applying the regulation of interrupting the test in this way is determined by the regulation of stable temperature of the test sample.
The determination of the duration at the test temperature in temperature testing is often based on the sample reaching temperature stability at that temperature. Due to differences in product structure, materials, and testing equipment capabilities, the time it takes for different products to reach temperature stability at the same temperature varies. When the surface of the test sample is heated (or cooled) and gradually transferred to the interior of the test sample. This thermal conduction process is a stable thermal conduction process, and there is a time delay when the internal temperature of the test sample reaches thermal equilibrium compared to the time when the surface of the test sample reaches thermal equilibrium. This time delay is the temperature stabilization time. For test samples that cannot measure temperature stability, the minimum required time is specified. That is, when not in operation and unable to measure, the minimum temperature stability time is 3 hours. When in operation, the minimum temperature stability time is 2 hours. In practical work, we use 2 hours as the temperature stability time. When the test sample reaches temperature stability, if the temperature around the test sample suddenly changes, there is a corresponding time delay for the test sample in thermal equilibrium, that is, in a short period of time, the temperature inside the test sample will not change too much.
During the experiment, if there is a sudden water or power outage or equipment failure, we should first seal the test chamber door, because when the test equipment suddenly stops running, as long as the door is sealed, the temperature of the test chamber door will not change sharply. In a short period of time, the temperature inside the test sample will not change too much; Then, determine whether the interruption has affected the test sample. If it has not affected the test sample and the test equipment can resume normal operation in a short period of time, we can continue the test according to the under test condition interruption handling method specified in GJB 150, unless the interruption has caused some impact on the test sample.
Dear customer:
Hello, our company is a high-quality development team with strong technical strength, providing high-quality products, complete solutions, and excellent technical services to our customers. The main products include walk-in constant temperature and humidity testing chambers, UV accelerated aging testing machines, rapid temperature change testing chambers, walk-in environmental testing chambers, UV aging testers, constant temperature and humidity chambers, etc. Our company adheres to the principle of building a business with integrity, maintaining quality, and striving for progress. With a more determined pace, we continuously climb new heights and contribute to the national automation industry. We welcome new and old customers to confidently choose the products they like. We will serve you wholeheartedly!
High and low temperature laboratory applications
Can determine whether the reliability and stability performance parameters of the product are qualified. Provide a basis for predicting and improving the quality and reliability of products. Structural characteristics of high and low temperature laboratory:
The high and low temperature laboratory adopts imported advanced temperature and humidity control instruments with PID regulation, fast self-tuning, programmable control of cyclic testing, multiple parameter settings, digital display, and extremely convenient reading;
The refrigeration system adopts an original imported high cooling capacity, high-efficiency maintenance free compressor. Adopting a binary cascade refrigeration method and imported environmentally friendly refrigerant, the cooling capacity is controlled by a servo control valve imported from the United States, saving about 30% energy (compared to our previous products).
The warehouse plate unit combination structure adopts internal stainless steel and external special steel plate spray coating treatment. The internal size can be expanded arbitrarily, and it is easy to disassemble and assemble. It can be customized according to customer requirements to match the site design appearance. Cooperate with customer migration.
A high-temperature resistant sealing strip is installed between the door and the shell of the walk-in constant temperature and humidity testing machine, effectively ensuring the sealing of the working room;
It has the functions of system parameter monitoring and equipment fault protection diagnosis. When there is a fault, it is accompanied by an alarm sound to prompt the fault handling measures, and at the same time, it is recorded in the book, which facilitates maintenance personnel to understand the medical history of the equipment. Improve maintenance quality and equipment stability.
Dear customer:
Hello, our company is a high-quality development team with strong technical strength, providing high-quality products, complete solutions, and excellent technical services to our customers. The main products include walk-in constant temperature and humidity testing chambers, UV accelerated aging testing machines, rapid temperature change testing chambers, walk-in environmental testing chambers, UV aging testers, constant temperature and humidity chambers, etc. Our company adheres to the principle of building a business with integrity, maintaining quality, and striving for progress. With a more determined pace, we continuously climb new heights and contribute to the national automation industry. We welcome new and old customers to confidently choose the products they like. We will serve you wholeheartedly!
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