Microstructure, Texture, and Mechanical Properties of Ni-W Alloy After Accumulative Roll Bonding

Abstract

In this study, the microstructure, texture, and mechanical properties evolution of Ni-14W (wt.%) alloy processed up to four cycles of accumulative roll-bonding (ARB) were investigated using electron backscatter diffraction, microhardness measurements, and tensile tests. The initial equiaxed grains, with an average size of 10 μm, underwent a strong refinement after ARB processing. The elongated ultrafine grains were parallel to the rolling direction, with a grain thickness of 0.2 µm. The texture after ARB processing was characterized by the typical rolling components (Copper, S and Brass), which showed a tendency toward stabilization after four cycles. The microhardness increased substantially (+ 86%) and seemed to saturate after three cycles. The tensile tests demonstrated that Ni-14W samples subjected to ARB processing exhibited high strength (> 1200 MPa after three ARB cycles) and very poor ductility.