High Cyclic Fatigue Characteristics of Gravity Cast AZ91 Magnesium Alloy Subjected to Transverse Load

Abstract

High cycle fatigue behavior of magnesium AZ91 alloy under transverse loading ambience is reported. An electro dynamic shaker system was used to apply transverse load on the specimen fabricated according to ASTM standard. The S–N curve for this novel test method for the alloy was generated and compared with the existing fatigue data. This assumes significance in the terrain of commercial applications, where the design of critical components is subjected to repeated transverse loads. Fatigue cracks were initiated at the pores in most of the samples. Considering the pores as the initial cracks, using linear fracture mechanics, critical stress intensity amplitude (Kcr) was estimated. Structure – fatigue property correlation was investigated by metallographic (optical and SEM) examination.