User:IgnitionMarketing/Physics of Failure

Physics of Failure (PoF) Physics of Failure (PoF), also known as Reliability Physics, applies analysis early in the design process to assess the reliability and durability of design alternatives in specific applications. It is a critical part of the Design for Reliability process as it enables designers to make design and manufacturing choices that minimize failure opportunities, which produces reliability optimized, robust products. Physics of Failure focuses on understanding the cause and effect physical process and mechanisms that cause degradation and failure of materials and components. It is based in the analysis of loads and stresses in an application and evaluating the ability of materials to endure them from a strength and mechanics of material point of view. This approach integrates reliability into the design process via a science-based process for evaluating materials, structures and technologies.

Other definitions of Physics of Failure

•US Army: An engineering-based approach to reliability that uses modeling and simulation to eliminate failures early in the design process by addressing root-cause failure mechanisms in a Computer-Aided-Engineering environment. •NASA-JPL: Modeling of failure mechanisms, based on science/engineering first principles, tat support deterministic or probablistic predictions fo reliability and provide a scientific basis for determining the effectiveness of screens or inspections.

While Physics of Failure is common in civil engineering and disciplines where fatigue or corrosion-induced wearout is a risk, it has not been as widely adopted in other industries.

Physics of Failure and the Electronics Industry Originally developed by Rome Air Development Center (RADC) in 1961 for integrated circuits (IC's), movement to circuit card and higher level integration was initially llimited by complexity, lack of wearout mechanisms.

Reliability is the measure of a product's ability to: •perform a specified function •in a customer-defined use environment •over a desired lifetime

Physics of failure therefore requires an understanding of the design, desired lifetime and use environment. •Design: Architecture + materials •Desired lifetime: When the customer will be satisfied •Use environment: Must include assembly, transportation, storage, operation

There is an increasing need for Physics of Failure in electronics design due to the introduction of limited-life technology into electronics components, products, and systems. Of special interest has been the effect of transistor aging and wear-out on the reliability of current and future generation microprocessors. In addition, the majority of electronic failures are thermo-mechanically related by thermally induced stresses and strains. As a result, a number of organizations including the US Department of Defense and the US Army are attempting to migrate from the empirical prediction methodology that has dominated electronics reliability prediction for decades to one more grounded in Physics of Failure.

Examples of standards that have already adopted Physics of Failure as a requirement: •VITA-51.2 •GEIA-STD-0009 •IPC SM-785