Fatigue Strength

Fatigue strength refers to the ability of a material or component to resist fatigue failure under cyclic loading, usually expressed as stress amplitude or number of cycles. In foreign trade, this term is commonly found in technical specifications, quality inspection reports, and contracts for mechanical parts, metal products, automotive components, and aviation parts. Usage scenarios include: customers requiring suppliers to provide fatigue strength data to verify product durability; contracts specifying that products must meet certain fatigue strength standards (e.g., ASTM, ISO); and quality inspection involving fatigue testing of samples and issuing reports. Note: Fatigue strength differs from static strength (e.g., tensile strength) in that the former focuses on life under cyclic loading, while the latter focuses on maximum stress under a single load. Different materials, heat treatments, and surface treatments all affect fatigue strength, so testing standards and acceptance conditions must be clarified before quoting and signing contracts. Difference from 'fatigue limit': Fatigue limit is the stress limit for infinite life, while fatigue strength can correspond to finite life.