Load direction and temperature impacts on cyclic creep behavior of laser-based powder bed fusion-produced WE43 magnesium alloy

Abstract

Magnesium alloys are renowned for their high strength-to-weight ratio and low density, making them highly sought-after in the lightweight engineering sector. Among these, the high-strength magnesium alloy WE43, characterized by its Mg-4Y-3RE composition, stands out for its superior mechanical strength and thermal stability. These properties, coupled with its creep resistance, render WE43 a suitable alloy in elevated temperature applications, particularly in aerospace and automotive engineering. Despite its potential, the characterization of the load direction- and temperature-dependent deformation behavior remains incomplete for WE43, especially in additive manufacturing contexts. This study explores the quasi-static and cyclic creep properties of WE43 produced via laser-based powder bed fusion. The research involved tensile and compression testing to evaluate quasi-static deformation and tensile-compression asymmetry. Cyclic creep behavior was studied under diverse mechanical (tension, compression) and thermal (RT, 200 °C, 300 °C) conditions by load-increase fatigue tests. Microstructural analyses based on cross-sections, XRD and computed tomography were conducted to assess manufacturing quality and identify potential inhomogeneities. The results reveal the interplay between mechanical load, temperature, and structural integrity in WE43. It could be shown that especially at 300 °C increased creep rates occure.