Effect of Texture on Fatigue Properties of an Extruded AZ61 Magnesium Alloy Plate

Abstract

Tensile and fatigue properties of extruded AZ61 magnesium alloy plate in different orientations of basal plane to the principal stress axis were investigated in a controlled air (20 -55%RH). A sinusoidal loading form with a stress ratio R=0.1 and a frequency of 20Hz was applied to the fatigue specimens. The specimen in 45 degree direction from the extruded direction showed lower tensile strength compared to those in the longitudinal and transverse directions, while it demonstrated the highest elongation. Fatigue strength of the specimen in the longitudinal direction was higher compared to those for the specimens in the transverse and 45 degree directions. Inclusions served as a fatigue crack initiation site for all specimens regardless of specimen orientation. It is suggested that the dominant basal plane texture strongly affects the tensile and fatigue properties of extruded magnesium alloys.

Effect of Processing Layer on Fatigue Strength of Extruded AZ61 Magnesium Alloy

“…Fatigue cracks were initiated at 26% with initial crack length of 24.8µm for PL specimen and 19% with initial crack length of 31.4µm for PL-P specimen, respectively. Crack initiation life observed in the present materials were the similar to that observed in generally in other magnesium alloys [4], however, fatigue crack initiation life of PL material was slightly longer than that of PL-P material and crack did not grow until 88% of the total fatigue life in PL material.…”