Ambient-Temperature Indentation Creep of an Additively Manufactured Ti-6Al-4V Alloy

Abstract

Instrumented indentation testing technique is a robust, convenient, and non-destructive characterization method to study time-dependent plastic deformation in metals and alloys at ambient and elevated temperatures. In this current research, the depth-sensing indentation creep behavior of additively manufactured Ti-6Al-4V alloy and its mechanism were studied at ambient temperature for different additive manufacturing scan direction and scan size. Indentation creep tests were conducted through a dual-stage scheme (loading followed by a constant load-holding) at different peak load of 250, 350, and 450 mN with holding time of 400 s. In addition, microstructural quantitative analyses, using optical microscopy and scanning electron microscopy, were performed. Microstructural assessments and depth-sensing creep characterizations were then used to assess processing parameter/ microstructure/ creep properties relationships for this alloy.