Microstructure and Mechanical Properties of Zr-Co-Ni Intermetallic Compound

Abstract

The relationship between the microstructure and mechanical properties on the ternary ZrCoNi alloys has been investigated. Zr50Co50-xNix alloys undergo martensitic transformation from the B2 to B33 structure by the substitution of Ni for Co. The tensile ductility at room temperature increases remarkably without the loss of yield strength by substituting Ni. Zr50Co39Ni11 alloy has the extremely high plastic elongation of 21%. There are many {021}B33 deformation twins in the B2 parent phase just near the tensile fractured area. These twins are the strain induced martensitic phase due to the tensile deformation. Consequently, the remarkable improvement of the ductility of ZrCoNi alloys is due to the transformation induced plasticity.