Effect of Tungsten Content on γ′ Strengthening Phase in Co-Al-W Alloy

In order to study the influence of tungsten element content on γ′ strengthening phase in Co-Al-W alloy,the alloys with different tungsten contents were prepared by combustion synthesis.The effect of tungsten content on the morphology ,amount and stablization of γ′ strengthening phase was studied by using SEM,XRD,EPMA and DSC.The results show that the microstructure of Co-Al-W alloy consisted of rich γ-Co matrix,γ′-Co3(Al,W) strengthening phase and less carbides.γ′-Co3(Al,W) strengthening phase was more stable than Co3Al phase.The liquidus temperature of the alloy increased and the amount of the strengthening phase increased as the W content inceased.The best stabilization effect of the element on the phase could obtain as the W content was 26.36wt%.