Effect of Hf on Microstructure and High-Temperature Strength of a Cast NiAl/Cr(Mo) Alloy
2001 Volume 42 Issue 8 Pages 1700-1704
Details
2001 Volume 42 Issue 8 Pages 1700-1704
A NiAl/Cr(Mo) alloy modified with Hf was fabricated by a vacuum induction melted and drop cast. The alloy was mainly composed of NiAl matrix, Cr(Mo) and Hf-rich phase distributed between NiAl and Cr(Mo) phase boundary and phase transition was also studied. Then it was hot isostically pressed (HIPed) at 1523 K, 200 MPa for 4.5 h. Its high temperature compressive behavior was studied and the deformation features of the alloy could be adequately described by standard power law which is usually used to characterize creep behavior for various metallic material. The stress exponent n as well as the activation energy Q was calculated by fitting the experimental data to the power-law and temperature-compensated power law equation. The possible strengthening mechanism was discussed.
