Al–Co–W fusion diagram in the Co–CoAl–W part

Chem. Met. Alloys 1 (2008) 338-342

https://doi.org/10.30970/cma1.0073

G. DMITRIEVA, V. VASILENKO, I. MELNIK

The fusion diagram of the Al–Co–W system in the Co–CoAl–W part was drawn using optical light, differential thermal, X-ray diffraction and electron microprobe analysis data. The alloys were prepared by arc melting. No ternary intermediate phase was found in this partial system above 900°C. The phase equilibria between CoAl and W were established with the peritectic reaction L+W↔CoAl at 1650ºC. The Co–CoAl–W fusion diagram has two isothermal three-phase fields corresponding to four-phase invariant reactions with participation of liquid: L↔Co+CoAl+Co₇W₆ (1380°C) and L+W↔Co₇W₆+CoAl (1490°C). The solidus and liquidus surface projections and the vertical sections for 75 at.% Co and equiatomic Al and W are presented and compared with the isothermal sections at 1200°C and 900°C reported earlier.

Solidus surface projection of the Al–Co–W system in the Co–CoAl–W part.

Keywords

Phase equilibria / Solubility / Fusion diagram / Solidus / Liquidus