Why is it significant to issue a professional failure analysis report?

Date：2021-09-09 14:55:39 Views：1987

The purpose of failure analysis of electronic components is to confirm the failure phenomenon of electronic components with the help of various test and analysis technologies and analysis procedures, distinguish their failure mode and failure mechanism, determine the cause of their final failure, put forward suggestions for improving design and manufacturing process, prevent the recurrence of failure and improve the reliability of components. Failure analysis is an important part of product reliability engineering. Failure analysis is widely used to determine the causes of production problems in the development and production process, identify reliability related failures in the test process, and confirm the field failure mechanism in the use process. In the development stage of electronic components, failure analysis can correct errors in design and development and shorten the development cycle; In the production, testing and use stage of electronic components, failure analysis can find out the failure causes of electronic components and the responsible party causing the failure of electronic components. According to the results of failure analysis, the component manufacturer improves the design and production process of components, the user of components improves the circuit board design, improves the testing, test conditions and procedures of components or the whole machine, and even replaces unqualified component suppliers on this basis. Therefore, failure analysis is of great significance to speed up the development of electronic components and improve the yield and reliability of components and the whole machine.

Failure analysis is to comprehensively analyze the macro and micro characteristics, materials, processes, physical and chemical properties, specified functions, stress state and environmental factors of the failed parts, judge the failure mode and cause, and put forward technical and management activities to prevent and correct the failure. In order to identify and analyze the fault mechanism, fault cause and fault consequence, the fault parts are studied logically and systematically.

Material failure mode

The failure modes of materials in various engineering applications mainly include fracture, corrosion, wear and deformation, among which fracture failure is the most harmful.

Elastic deformation failure

When the recoverable elastic deformation of the material caused by stress or temperature is enough to affect the normal function of the equipment, the elastic deformation will fail.

Plastic deformation failure

When the plastic deformation of the load material that cannot be recovered is enough to affect the normal predetermined function of the equipment, the plastic deformation will fail.

Ductile fracture failure

The fracture with obvious macroscopic plastic deformation before material fracture is called ductile fracture fault.

Brittle fracture failure

The fracture that does not occur before the material fracture or has less macroscopic visible plastic deformation is called brittle fracture fault.

Fatigue fracture failure

The fracture of materials under alternating load after a certain period is called fatigue fracture fault.

Corrosion failure

Corrosivity refers to the physical or chemical reaction between the surface of the material and the use environment, resulting in damage or deterioration of the material, and the corrosivity of the material makes it unable to play its normal role, which is called corrosive failure. There are many forms of corrosivity, including uniformly distributed corrosivity on the material surface and locally distributed corrosivity on the material surface. Local corrosion can be divided into pitting corrosion, intergranular corrosion, crevice corrosion, stress corrosion crack, corrosive fatigue, etc.

Wear failure

When materials are in contact with each other or the material surface is in contact with fluid and moves relative to each other, the shape, size or quality of the material surface changes due to physical and chemical effects, which is called wear. The loss of component function caused by wear is called wear failure. There are many forms of wear, including adhesion wear, wear, impact wear, fretting wear, corrosion wear, fatigue wear and so on.

Failure modes of polymers and composites

Common failure modes of metal materials and parts include fracture (ductile fracture, brittle fracture, fatigue fracture, stress corrosion fracture, fatigue fracture, creep fracture, liquid metal brittleness, hydrogen embrittlement), corrosion (chemical corrosion, electrochemical corrosion), wear (abrasive wear, adhesive wear, fatigue wear, fretting wear, deformation wear), etc.

The main failure modes of polymer materials are fracture, cracking, corrosion, delamination, blistering, falling off, discoloration, wear and so on.

The main failure modes of composites are crack, corrosion, plate layer explosion, open circuit (line, hole), discoloration and so on.

What is the significance of failure analysis?

1. Failure analysis is to find out the failure causes and take effective measures to prevent similar failure accidents from recurring, so as to avoid great economic losses and casualties;

2. Promote the development of science and technology

During the industrial revolution in the 19th century, the use of steam engine promoted railway transportation, but many train shaft fracture and train derailment accidents occurred continuously.

A large number of broken shaft analysis and experimental research show that the cracks start from the sharp corner of the inner edge of the wheel seat. It is recognized that under alternating stress, even if the stress is far lower than the tensile strength of the metal, it will break after a certain cycle accumulation, that is, "fatigue"

"Fatigue fracture" has become an important field in the strength of metal materials. The fatigue testing machine is designed, the concept of fatigue limit is determined, and the anti fatigue design method is put forward.

During World War II, the United States had 4694 "free ships" with welded structures, and 1289 failed to varying degrees. Among them, 238 were broken in two or seriously damaged and scrapped, 19 sank and 24 decks were completely broken.

After the war, a large number of failure cause analysis studies were carried out, and it was recognized that the notch sensitivity of steel and the low-temperature embrittlement of steel. That is, carbon steel and low alloy steel have brittle transition temperature, which will become brittle below a certain temperature (very sensitive to notch).

From 1940s to 1950s, many flying cracks of power station equipment and crashes of British air force occurred in the United States. The results of failure analysis show that the harmful effects of hydrogen and inclusions in steel. Since then, the basic theory of hydrogen embrittlement of steel has been established. Therefore, alkaline and vacuum smelting technology has been developed to promote the development of metallurgical technology.

3. Promote the provision of quality, safety and reliability of mechanical products

Reliability is the key quality index of products, and reliability technology is the harmony of quality assurance. One of the prerequisites of reliability analysis is to confirm whether the product fails, analyze the failure type, failure mode and failure mechanism.

Part failure is related to design, material selection, manufacturing, inspection, installation and other processes. Through failure analysis, the failure causes and preventive measures are continuously fed back to the relevant design departments for corresponding improvement to promote the improvement of product quality and reliability.

4. Failure analysis provides the basis for formulating or modifying technical standards

5. Failure analysis is also an important basis for arbitrating failure accidents, developing technical insurance business and claims in foreign trade

According to the introduction of the chip unsealing laboratory, it can carry out testing according to international, domestic and industrial standards, carry out comprehensive testing from the underlying chip to the actual product, from physics to logic, and provide chip preprocessing, side channel attack, optical attack, intrusive attack, environment, voltage burr attack, electromagnetic injection, radiation injection, physical security, logic security, function Compatibility, multipoint laser injection and other safety detection services. At the same time, it can carry out failure analysis and detection services to simulate and reproduce the failure of intelligent products and find out the failure causes, mainly including probe station, reactive ion etching (RIE), micro leakage detection system (Emmi), X-ray detection, defect cutting observation system (FIB system) and other detection tests. Realize the evaluation and analysis of the quality of intelligent products, and provide quality assurance for chips, embedded software and applications of intelligent equipment products.