BEHAVIOUR OF Co5Cr3Si2 PHASE IN Cu-RICH ALLOYS CONTAINING Co,Cr AND Si

The major phases in the Cu-rich alloys containing Co,Cr and Si are α-Cu(a solid solutionof Co,Cr and Si in Cu),χ-phase(CoCrSi)and CoSi.In comparison with referencesample,it has been detected that the crystal structure of CoCrSiis cubic,α-Mn type witha=0.8694 nm.The melting temperature of χ-phase and the alloy are higher than that of thepure Cu,namely,1535 and 1389 K respectively.During ageing treatment,the CoSi phaseprecipitates out from α-Cu and χ-phase simultaneously,but the hardening effect is mainlycontributed by the precipitation from α-Cu.