Experimental Determination of Isothermal Section in a Ni-Cr-W Ternary System at 1 000°C

Abstract

An isothermal section of an equilibrium phase diagram in a Ni-Cr-W ternary system was experimentally determined at 1 000°C. Seventeen alloys with multiphase composition were equilibrated at 1 000°C for more than 10 000 h. Three terminal solid solutions: fcc γ nickel-rich, bcc α₁chromium-rich and bcc α₂ tungsten-rich phase, and two intermetallic compounds: β-Ni₄W and σ phase, were observed as stable phases. Two-phase tie-lines and three-phase tie-triangles were determined by means of an electron microprobe analysis.