Bolt Load Compressive Stress Retention Testing of Magnesium Alloys

Elevated temperature bolt load compressive stress retention testing of four high temperature magnesium alloys (AJ50X, AJ52X, AS21X and AE42), two structural magnesium alloys (AM50A and AM60B), one aluminum alloy (383) and one gray iron alloy were performed at the INTERMET Technical Center over a period of about one year. Artificial aging of some of these alloys during testing was observed. The effect of a heat treatment designed to thermally stabilize the microstructure was evaluated and determined to significantly improve magnesium performance and degrade aluminum performance. This paper documents the test procedure and the test results.