Compressive properties of high-pressure die cast IP 75 alloy with strengthening Laves phase

Abstract

The NiAl–2Ta–7.5Cr–0.5Nb alloys (IP 75 alloy) were prepared by high-pressure die cast (HPDC), and tested for compressible strength and fracture behavior in the temperature range 300–1373 K. The fine structures with a homogeneous distribution of Laves phase at the boundary regions created by high-pressure die cast led to improvements in both the compressible yield strength and fracture strain. The high temperature (1373 K) 0.2% compressible yield strength of the HDC IP 75 alloy (160 MPa) is larger than that of the IP 75 alloys prepared by other processes. The room-temperature compressible fracture strain of the HDC IP 75 (14%) is also superior to the IP 75 alloy (5%) prepared by an ingot-casting process. The effects of size refinement and the more homogenous distribution of Laves phase and the formation of a ductile Cr-rich phase due to a rapid solidification contribute to the increments of the compressible yield strength and the fracture strain of the HPDC alloy.