Importance and purpose of product reliability test
Date：2021-04-26 16:19:00 Views：1360
The ability or possibility of the product to perform the specified function without failure under certain time or conditions. The reliability of products can be evaluated by reliability, failure rate and mean time between failures. Moreover, this is an important quality index. Only qualitative description is not enough. It must be quantified in order to make accurate description and comparison.
Reliability is closely related to the development of electronic industry. Its importance can be explained from the three characteristics of the development of electronic products.
First, the complexity of electronic products is increasing. The first ore radio used by people is very simple. Then there have been various types of radios, tape recorders, video cameras, communicators, radars, guidance systems, electronic computers and aerospace control equipment, with increasing complexity. The significant sign of the complexity of electronic products is the number of components required. The reliability of electronic products depends on the reliability of the components used, because the failure of any component and solder joint in electronic products will lead to system failure. Generally speaking, the more components used in electronic products, the more serious the reliability problem. In order to ensure the reliable operation of products or systems, the requirements for the reliability of components are very high and demanding.
Secondly, the use environment of electronic products is becoming increasingly harsh. From the laboratory to the field, from the tropics to the cold zone, from the land to the deep sea, from the high altitude to the space, they are subjected to different environmental conditions. In addition to the effects of temperature and humidity, the effects of seawater, salt fog, impact, vibration, cosmic particles and various radiation on electronic components increase the possibility of product failure.
Third, the device density of electronic products is increasing. From the first generation of electronic tube products to the second generation of transistors, and now from small and medium-scale integrated circuits to large-scale and super large-scale integrated circuits, electronic products are developing in the direction of miniaturization and miniaturization, which leads to the continuous increase of device density, resulting in the increase of internal temperature and the deterioration of heat dissipation conditions. The reliability of electronic components will decrease with the increase of ambient temperature, so the reliability of components has attracted great attention.
The test to measure, verify or improve product reliability is called reliability test. It is an important link of product reliability. Usually, the product is testedPurpose of reliability testAs follows:
(1) In the development stage, make the product reach the predetermined reliability index. In order to make the product reach the predetermined reliability index, it is necessary to carry out reliability test on the samples in the development stage, so as to find out the problems existing in the raw materials, structure, process and environmental adaptability of the product and improve them. After repeated test and improvement, the reliability indexes of the product can be continuously improved to meet the predetermined requirements.
(2) Conduct reliability appraisal during product development and finalization. During the development and finalization of new products, identification tests shall be carried out according to product standards (or product technical conditions), so as to comprehensively assess whether the products meet the specified reliability indicators.
(3) Control the quality of products in the production process. In order to produce products stably, it is sometimes necessary to conduct reliability test for each product according to the items specified in the product technical conditions. In addition, reliability sampling test shall be carried out batch by batch or within a certain period. The stability of product quality can be understood through the reliability test of products. If the product quality drops due to poor quality of raw materials or out of control of process flow, it can be reflected in the product reliability test, so that corrective measures can be taken in time to restore the product quality to normal.
(4) Screen the products to improve the reliability of the whole batch of products. Reasonable screening can eliminate the early failure products caused by various reasons (such as defective raw materials, improper process measures, negligence of operators, failure of production equipment and lax quality inspection, etc.), so as to improve the reliability level of the whole batch of products.
(5) Study the failure mechanism of the product. Through the product reliability test (including simulation test and field use test), we can understand the failure mode and failure law of the product under different environments and different stress conditions. Through the analysis of failed products, the internal causes (i.e. failure mechanism) and weak links of products can be found out, so that corresponding measures can be taken to improve the reliability level of products.
The development of reliability engineering can drive and promote the development of product design, manufacturing, use, materials, technology, equipment and management, and raise electronic components and other electronic products to a new level. It has been listed as an important quality index of products for assessment and inspection. In a sense, reliability can comprehensively reflect the quality of products. Reliability engineering is a comprehensive discipline. Its development can drive and promote the development of product design, manufacturing, use, materials, technology, equipment and management, and raise electronic components and other electronic products to a new level. Because of this, reliability has formed a special discipline to be studied as a special technology.