Review of the Mechanical Properties of High-Strength Alloys at Cryogenic Temperatures

To advance the understanding of metallic materials for structural components at cryogenic temperatures, a review of previous studies on the mechanical properties of austenitic stainless steels, titanium alloys, aluminum alloys, and copper alloys is presented herein. In particular, the evaluation of strength and toughness balance intends to clarify key differences between these alloys to facilitate better alloy design and potentially bolster further alloy development. Several key points on cryogenic mechanical tests are also introduced. Temperature control, testing tools, and test conditions should be properly calibrated to avoid experimental errors. Furthermore, substantial progress for subsurface crack initiation in high-cycle fatigue at cryogenic temperatures is presented, in which the mechanism of subsurface crack generation is highlighted as a key design consideration in microstructure of high-strength alloys.