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Environmental Stress Screening
Environmental stress screening (ESS) refers to the process of exposing a newly manufactured or repaired product or component (typically electronic) to stresses such as thermal cycling and vibration in order to force latent defects to manifest themselves by permanent or catastrophic failure during the screening process. The surviving population, upon completion of screening, can be assumed to have a higher reliability than a similar unscreened population. Overview Developed to help electronics manufacturers detect product defects and production flaws, ESS is widely used in military and aerospace applications, less so for commercial products. The tests need not be elaborate, for example, switching an electronic or electrical system on and off a few times may be enough to catch some simple defects that would otherwise be encountered by the end user very soon after the product was first used. Tests typically include the following: * Temperature variations * Vibration tests * Pressure ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electronic Component
An electronic component is any basic discrete device or physical entity in an electronic system used to affect electrons or their associated fields. Electronic components are mostly industrial products, available in a singular form and are not to be confused with electrical elements, which are conceptual abstractions representing idealized electronic components and elements. Electronic components have a number of electrical terminals or leads. These leads connect to other electrical components, often over wire, to create an electronic circuit with a particular function (for example an amplifier, radio receiver, or oscillator). Basic electronic components may be packaged discretely, as arrays or networks of like components, or integrated inside of packages such as semiconductor integrated circuits, hybrid integrated circuits, or thick film devices. The following list of electronic components focuses on the discrete version of these components, treating such packages as compone ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MIL-STD 461
MIL-STD-461 is a United States Military Standard A United States defense standard, often called a military standard, "MIL-STD", "MIL-SPEC", or (informally) "MilSpecs", is used to help achieve standardization objectives by the U.S. Department of Defense. Standardization is beneficial in achievi ... that describes how to test equipment for electromagnetic compatibility. The United States Department of Defense issued MIL-STD-461 in 1967 to integrate electromagnetic compatibility into the research and development stage for defense communications technology. Various revisions of MIL-STD-461 have been released. Many military contracts require compliance to MIL-STD-461E. The latest revision (as of 2015) is known as "MIL-STD-461G". While MIL-STD-461 compliance is technically not required outside the US military, many civilian organizations also use this document. In 1999, MIL-STD-462 was combined with MIL-STD-461D into MIL-STD-461E. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Highly Accelerated Life Test
A highly accelerated life test (HALT) is a stress testing methodology for enhancing product reliability in which prototypes are stressed to a much higher degree than expected from actual use in order to identify weaknesses in the design or manufacture of the product. Manufacturing and research and development organizations in the electronics, computer, medical, and military industries use HALT to improve product reliability. HALT can be effectively used multiple times over a product's life time. During product development, it can find design weakness earlier in the product lifecycle when changes are much less costly to make. By finding weaknesses and making changes early, HALT can lower product development costs and compress time to market. When HALT is used at the time a product is being introduced into the market, it can expose problems caused by new manufacturing processes. When used after a product has been introduced into the market, HALT can be used to audit product reliabil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Highly Accelerated Stress Screen
A highly accelerated life test (HALT) is a stress testing methodology for enhancing product reliability in which prototypes are stressed to a much higher degree than expected from actual use in order to identify weaknesses in the design or manufacture of the product. Manufacturing and research and development organizations in the electronics, computer, medical, and military industries use HALT to improve product reliability. HALT can be effectively used multiple times over a product's life time. During product development, it can find design weakness earlier in the product lifecycle when changes are much less costly to make. By finding weaknesses and making changes early, HALT can lower product development costs and compress time to market. When HALT is used at the time a product is being introduced into the market, it can expose problems caused by new manufacturing processes. When used after a product has been introduced into the market, HALT can be used to audit product reliabil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MIL-STD-810
MIL-STD-810, U S Department of Defense Test Method Standard, Environmental Engineering Considerations and Laboratory Tests, is a United States Military Standard that emphasizes tailoring an equipment's environmental design and test limits to the conditions that it will experience throughout its service life, and establishing chamber test methods that replicate the effects of environments on the equipment rather than imitating the environments themselves. Although prepared specifically for U.S. military applications, the standard is often applied for commercial products as well. The standard's guidance and test methods are intended to: * define environmental stress sequences, durations, and levels of equipment life cycles; * be used to develop analysis and test criteria tailored to the equipment and its environmental life cycle; * evaluate equipment's performance when exposed to a life cycle of environmental stresses * identify deficiencies, shortcomings, and defects in equipment ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Failure Analysis
Failure analysis is the process of collecting and analyzing data to determine the cause of a failure, often with the goal of determining corrective actions or liability. According to Bloch and Geitner, ”machinery failures reveal a reaction chain of cause and effect… usually a deficiency commonly referred to as the symptom…”. failure analysis can save money, lives, and resources if done correctly and acted upon. It is an important discipline in many branches of manufacturing industry, such as the electronics industry, where it is a vital tool used in the development of new products and for the improvement of existing products. The failure analysis process relies on collecting failed components for subsequent examination of the cause or causes of failure using a wide array of methods, especially microscopy and spectroscopy. Nondestructive testing (NDT) methods (such as industrial computed tomography scanning) are valuable because the failed products are unaffected by analysis, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Environmental Tests
{{noref, date=January 2021 Environmental testing is the measurement of the performance of equipment under specified environmental conditions, such as: * extremely high and low temperatures * large, swift variations in temperature * blown and settling sand and dust * salt spray and salt fog * very high or low humidity * wet environments, waterproofness, icing * presence of corrosive material * fungus, fluids susceptibility * vibrations (airborne and structural), gun fire * accelerations * solar radiation * high and low pressures (especially for aeronautical and space equipment) * operating at angles (especially for marine, aeronautical and space equipment) * electromagnetic interference (EMI), ESD, Lightning * acoustic measurements * power input variations Such tests are most commonly performed on equipment used in military, maritime, aeronautical and space applications. See Environmental test chambers for more information about environmental testing equipment. Environmental test st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Environmental Chamber
An environmental chamber, also called a climatic chamber or climate chamber, is an enclosure used to test the effects of specified environmental conditions on biological items, industrial products, materials, and electronic devices and components. Such a chamber can be used: # as a stand-alone test for environmental effects on test specimens # as preparation of test specimens for further physical tests or chemical tests # as environmental conditions for conducting testing of specimens Overview An environmental test chamber artificially replicates conditions which machinery, materials, devices or components might be exposed to. It is also used to accelerate the effects of exposure to the environment, sometimes at conditions not actually expected. Chamber testing involves testing and exposing products to various environmental conditions in a controlled setting. Climatic Chamber testing and Thermal Shock testing are part of chamber testing. Climatic Chamber testing is a broad c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Accelerated Aging
Accelerated aging is testing that uses aggravated conditions of heat, humidity, oxygen, sunlight, vibration, etc. to speed up the normal aging processes of items. It is used to help determine the long-term effects of expected levels of stress within a shorter time, usually in a laboratory by controlled standard test methods. It is used to estimate the useful lifespan of a product or its shelf life when actual lifespan data is unavailable. This occurs with products that have not existed long enough to have gone through their useful lifespan: for example, a new type of car engine or a new polymer for replacement joints. Physical testing or chemical testing is carried out by subjecting the product to * representative levels of stress for long time periods, * unusually high levels of stress used to accelerate the effects of natural aging, or * levels of stress that intentionally force failures (for further analysis). Mechanical parts are run at very high speed, far in excess o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IEST
The Institute of Environmental Sciences and Technology (IEST) is a non-profit, technical society where professionals who impact controlled environments connect, gain knowledge, receive advice, and work together to create industry best practices. The organization uniquely serves environmental test engineers, qualification engineers, cleanroom professionals, those who work in product testing and evaluation, and others who work across a variety of industries, including: acoustics, aerospace, automotive, biotechnology/bioscience, climatics, cleanroom operations/design/equipment/certification, dynamics, filtration, food processing, HVAC design, medical devices, nanotechnology, pharmaceutical, semiconductors/microelectronics, and shock/vibration. Information on ISO 14644 and ISO 14698 standards can be found through this organization. Founded in 1953, the organization is headquartered in Schaumburg, Illinois. Its members are internationally recognized in the fields of environmental test ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States Department Of Defense
The United States Department of Defense (DoD, USDOD or DOD) is an executive branch department of the federal government charged with coordinating and supervising all agencies and functions of the government directly related to national security and the United States Armed Forces. The DoD is the largest employer in the world, with over 1.34 million active-duty service members (soldiers, marines, sailors, airmen, and guardians) as of June 2022. The DoD also maintains over 778,000 National Guard and reservists, and over 747,000 civilians bringing the total to over 2.87 million employees. Headquartered at the Pentagon in Arlington, Virginia, just outside Washington, D.C., the DoD's stated mission is to provide "the military forces needed to deter war and ensure our nation's security". The Department of Defense is headed by the secretary of defense, a cabinet-level head who reports directly to the president of the United States. Beneath the Department of Defense are th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bathtub Curve
The bathtub curve is widely used in reliability engineering and deterioration modeling. It describes a particular form of the hazard function which comprises three parts: *The first part is a decreasing failure rate, known as early failures. *The second part is a constant failure rate, known as random failures. *The third part is an increasing failure rate, known as wear-out failures. The name is derived from the cross-sectional shape of a bathtub: steep sides and a flat bottom. The bathtub curve is generated by mapping the rate of early "infant mortality" failures when first introduced, the rate of random failures with constant failure rate during its "useful life", and finally the rate of "wear out" failures as the product exceeds its design lifetime. In less technical terms, in the early life of a product adhering to the bathtub curve, the failure rate is high but rapidly decreasing as defective products are identified and discarded, and early sources of potential failure s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
