Structure and mechanical properties of Ni-Cr alloy produced by single roll strip casting

Abstract

In the present investigation the microstructure and some mechanical properties of Ni-Cr alloy prepared by single roll strip casting (SRSC) were studied. The top surface (surface not in contact with the roll) of the as received sample was rough and lusterless. The grain size of the top surface was significantly larger compared to that of the bottom surface. Grain interior showed dendritic morphology. Etch-pits, formed by dislocation were observed on the top and bottom surfaces of the sample. Scanning electron microstructure revealed continuous corroded region along the grain boundaries. X-ray diffraction (XRD) study confirms the formation of chromium carbide at the grain boundary, which depletes Cr near the grain boundary. The hardness of the top surface is lower compared to the bottom surface. The cross-sectional surface shows much higher hardness compared to top and bottom surface, suggesting anisotropic nature of the alloy. The tensile properties of the sample were affected by chromium carbide precipitation at grain boundaries. Crown Copyright (C) 2009 Published by Elsevier Ltd. All rights reserved.