Effect of Lanthanum Doping Method on Properties of La-TZM Alloy

Abstract:

Based on TZM molybdenum alloy, La-TZM alloy sheets, with solid-solid doping of rare earth La2O3 or liquid-solid doping of La(NO3)3, were manufactured by sintering, hot rolling, warm rolling and cold rolling. The powder morphology, microstructures of sintering compact and fracture morphology of the alloy sheets were observed by SEM, and the alloy powder particle size and alloy composition were analyzed by particle size distribution and EDS, respectively. The results show that the distribution of the second phase in the La(NO3)3 doped TZM alloy sheets is more uniform than that in La2O3 doped TZM alloy sheets. The grain size of La(NO3)3 doped TZM alloy is finer. Besides, the tensile strength of La(NO3)3 doped TZM alloy is much higher than that of La2O3 doped alloy, which increases by 10.9%.

Key words:La2O3; TZM alloy; molybdenum powder; tensile strength; elongation; fracture morphology