Search Results for fatigue properties

Fatigue failure is a critical performance metric for additively manufactured (AM) metal parts, especially those intended for safety-critical structural applications (i.e., applications where part failure causes system failure and injury to users). This article discusses some of the common defects that occur in laser powder bed fusion (L-PBF) components, mitigation strategies, and their impact on fatigue failure. It summarizes the fatigue properties of three commonly studied structural alloys, namely aluminum alloy, titanium alloy, and nickel-base superalloy.

This article describes the fatigue properties of particle-reinforced metal-matrix composites (PR-MMCs) in terms of mechanisms of crack initiation, fatigue life, and fatigue crack growth. It reviews specimen preparation and microscopic procedures that are used in fatigue testing of MMCs. It also describes the evaluation of the long fatigue crack growth behavior of MMCs by using the test methods and specimens that are used for unreinforced metallic alloys. Fractography of MMCs under plane-strain conditions is also described with information on the observed features of MMC fatigue fracture surfaces and their observation methods.

Copper alloys are classified by the International Unified Numbering System designations to identify alloy groups by major alloying element. This article presents the designations and compositions of various copper alloys, such as brasses, nickel silvers, bronzes, beryllium coppers, and spinodal alloys. It discusses the fatigue testing of the copper alloys and tabulates the tensile and fatigue strengths of the copper alloys. The article schematically illustrates S-N curves for the solid-solution (non-aging) strengthened alloys. It concludes with a discussion on the role of microstructure in the fatigue performance of beryllium copper alloys.

Fatigue properties are an integral part of materials comparison activities and offer information for structural life estimation in many engineering applications. This article presents three general approaches to fatigue design, with a discussion on their respective attributes. These include infinite-life criterion, finite-life criterion, and damage tolerant criterion. The article describes the individual property requirements of these approaches. It also presents selected examples of properties that reflect some detail of these approaches.

This article provides information on fracture toughness and fatigue crack growth of structural steels. It describes fatigue life behavior in terms of unnotched fatigue limits, notch effects, axial strain-life fatigue, and mean stress effects. The article analyzes the mechanisms of corrosion fatigue crack initiation and prevention of corrosion fatigue. It presents case histories of fatigue failure of various steel components. The article reviews the failure of coiled tubing in a drilling application and the failure of coiled tubing due to hydrogen sulfide exposure, with examples.