Deformation Mechanisms in High-Purity Fe–50Cr(–5W) Alloys at Elevated Temperatures

Abstract

The deformation mechanisms in high-purity Fe–50Cr(–5W) alloys were investigated between 293 and 773 K by tensile tests and by TEM observations of the fractured specimens. The results of the TEM observation have shown the following. 1. Fe–50Cr alloys deform by dislocation slip and twinning. 2. Four types of twin–matrix interfaces are observed in high-purity Fe–50Cr(–5W) alloys after deformation, normal type, zigzag type, wavy type and abnormal type. 3. The planar slip traces are seen on the Fe–50Cr alloy after deformation at 293 and 573 K and the addition of tungsten restrains the local deformation. The results of the tensile test have shown the following. 4. The addition of tungsten to an Fe–50Cr alloy increases the amount of twinning at every temperature and the elongation of high-purity Fe–50Cr alloy increases dramatically at 773 K due to uniform dislocation slip.