A Study of the Phase Diagram for the Mo-Zr-C System in a Region Rich in Molybdenum

摘要

A series of Mo-Zr-C alloys containing 0-0.55% wt. C, 0-6.0% wt. Zr, and about 0.011% O, 0.008% N, and 0.0006% H impurities, were melted from single crystal molybdenum, 99.94 percent - pure Zr, lamp black and spectrally pure zirconium carbide (ZrC) in a nonconsumable-electrode arc furnace in a helium atmosphere. The alloys were investigated by various methods of physicochemical and phase analyses in the ascast condition and also after vacuum annealing and quenching from temperatures ranging from 1970 to 1250C. On the basis of the results obtained, isotherms were plotted for the solidus surface of molybdenum alpha-solid solution in the ternary Mo-Zr-C system, and also isothermal sections at 1970 and 1250C, and a polythermal Mo-Zr-C section. (Author)