High temperature mechanical properties of Ni-Al-Cr based alloys for advanced die-materials applications

In this study, we report on advanced Ni3Al based high temperature structural alloys with Zr and B addition in order to apply in the fields of die-casting and high temperature press forming as die materials. Microstructures and mechanical properties of Ni3Al based intermetallic alloys produced by vacuum arc melting were investigated in terms of phase analysis by using a scanning electron microscope (SEM) equipped with an X-ray energy dispersive spectrometer (EDS), an X-ray diffractometer (XRD) and tensile test. The duplex microstructural feature consisting of gamma' matrix phase and small intermetallic dispersoids was observed to be distributed over the whole microstructure. The ultimate tensile strength of the present alloy was superior to commercial iron-based and Ni-based die-materials especially in the high temperature region.