Comparison of Processing on the Mechanical and Microstructure of Powder Metallurgy Molybdenum 41 and 47.5 Rhenium

摘要

Rhenium and rhenium containing alloys are unique metals with high melting points, high moduli of elasticity and high temperature mechanical properties. The most common rhenium containing alloys are molybdenum-41wt% rhenium (Mo41%Re) and molybdenum-47.5wt% rhenium (Mo47.5%Re). The focus of this study is to examine the mechanical properties and microstructures of hot isostatic pressed, hot rotary swaged, hot rolled and hot rolled and annealed Mo41%Re and Mo47.5%Re alloys. Both alloys are BCC solid solution alloys with work hardening rates half of commercial-purity rhenium. Unlike pure molybdenum, Mo41% and Mo47.5% and rhenium have excellent cold and warm plasticity. Adding rhenium to molybdenum increases the ductility as the rhenium concentration increases. The primary deformation mechanism of Mo47.5 Re alloys is twinning. Twinning occurs during cold and warm working, enhancing the mechanical properties without sacrificing ductility yet maintaining good strength at elevated temperatures. This study will discuss the results of the differences in rhenium concentration and processing methods on the texture, microstructure, and the mechanical properties at room temperature and at elevated temperature.