Reliability testing refers to determining and verifying the reliability of a product through experimentation. Research on identifying weak links in products with limited samples, time, and usage costs. Reliability testing is a general term for various tests conducted to understand, evaluate, analyze, and improve the reliability of products.
Reliability testing method:
1. Timing truncation test: Refers to setting a test time in advance, and stopping the test when the specified time is reached. The number of samples with faults in the sample is random and cannot be known in advance.
2. Sequential experiment: also known as sequential analysis, involves conducting experiments on existing samples one by one or pair by pair, in a sequential and coherent manner, until the specified results are achieved and the experiment is concluded. Its characteristic is that this type of experiment can avoid blindly increasing the number of test samples and causing waste, and will not fail to draw conclusions due to too few test samples - saving samples (saving 30-50% of samples compared to general experimental methods). The commonly used sequential experimental methods include the split method, 0.618 method, fractional method, parabolic method, hill climbing method, and batch experiment method.
3. Reliability Growth Test: A planned Test Analysis Improvement (TAAF) process that involves applying real or simulated comprehensive environmental stress to a product, exposing potential defects, and taking corrective measures to achieve predetermined reliability requirements. It is worth noting that reliability growth activities are not aimed at poorly designed products, but at products that, despite careful design, still cannot meet requirements due to certain technical reasons. Remember: the core of reliability growth is to eliminate design defects that affect it. However, the attitude of placing reliability levels on growth activities is incorrect.
4. High acceleration life test, abbreviated as HALT test, is a qualitative testing method for design quality verification and manufacturing quality verification extended from the United States. It uses a rapid high and low temperature oscillation system to reveal design defects and deficiencies in electronic and mechanical assemblies. The HALT test chamber can provide a temperature range of -100 ℃ to+200 ℃, with a temperature rate of up to 70 ℃ to 100 ℃/min. At the same time, provide six axis random vibration (vibration intensity 0-75Grms, frequency range 1Hz-1MHz). ）Transmitting high vibration energy in the low-frequency range to stimulate potential defects in large products. HALT advantage: Quickly detect defects and eliminate opportunities for malfunctions; Evaluate inefficiency and MTBF, validate standards.
The HAST high acceleration life test chamber developed by ZONGLEN is mainly used to evaluate the reliability of products or materials in humid environments. It is achieved by setting and creating various conditions of temperature, humidity, and pressure in a highly controlled pressure vessel, which accelerates the penetration of moisture through external protective plastic packaging and applies these stress conditions to the material body or the interior of the product. Compared to traditional high-temperature and high humidity testing, HAST increases the pressure inside the container, enabling temperature and humidity control under conditions exceeding 100 ℃. This can accelerate the aging effects of temperature and humidity (such as migration, corrosion, insulation degradation, material aging, etc.), greatly shorten the reliability evaluation testing cycle, and save time and cost. HAST high accelerated aging testing has become a standard in certain industries, especially in products such as PCBs, semiconductors, solar energy, display panels, etc., as a fast and effective alternative to standard high-temperature and high humidity testing.