In order to improve the low ductility of the Mo-Ni alloy,Fe is added and the effects of Ni/Fe mass ratio on the densification behavior,microstructure evolution and mechanical properties of alloy were investigated.The ...In order to improve the low ductility of the Mo-Ni alloy,Fe is added and the effects of Ni/Fe mass ratio on the densification behavior,microstructure evolution and mechanical properties of alloy were investigated.The experimental results show that when iron is added to 95Mo-5Ni alloy,the formation of brittle intermetallic phaseδ-MoNi at the grain boundary is avoided.Meanwhile,the grain growth of Mo is also effectively inhibited in the sintering process.However,the addition of iron reduces the degree of densification of alloy since the activation effect of Ni is superior to that of Fe.From the experimental results,it could be concluded that the maximum hardness and bending strength are achieved by 95Mo-1.5Ni-3.5Fe alloy,which are HV 614 and 741 MPa,respectively.Combined with the analyses of bending fracture mechanism,the improvement relative to Mo-Ni alloy is likely attributed to the inhibition of the brittle phase.展开更多
Hot roll bonding was carried out between commercially pure titanium TA2 and high-strength low-alloy steel Q390 using pure Nb or Mo interlayer at 950 ~C with a total reduction ratio of 86.7%. Interfacial microstructure...Hot roll bonding was carried out between commercially pure titanium TA2 and high-strength low-alloy steel Q390 using pure Nb or Mo interlayer at 950 ~C with a total reduction ratio of 86.7%. Interfacial microstructure and bonding properties of titanium clad steel plates were investigated by electron microscopy and mechanical tests. The results showed β-Ti, TiC and Fe2Ti reaction phases were generated at Ti/steel interface for the clad plates with no interlayer. Inserting Nb or Mo interlayer can effectively suppress the formation of brittle phases, while the weak bonding joint transferred to Nb/steel or Mo/steel interface. And some micro-voids were found at the interface of Nb/steel and Mo/steel. The improved shear strength of clad plates with Nb interlayer might be attributed to the elimination of brittle phases at bonding interface. The small size and little quantities of the micro-voids at Nb/steel interface had a relatively weak effect on shear strength. However, the large number and big size of micro-voids were responsible for the degradation of shear strength for the clad plates with Mo interlayer.展开更多
基金Project(51734002)supported by the National Natural Science Foundation of China。
文摘In order to improve the low ductility of the Mo-Ni alloy,Fe is added and the effects of Ni/Fe mass ratio on the densification behavior,microstructure evolution and mechanical properties of alloy were investigated.The experimental results show that when iron is added to 95Mo-5Ni alloy,the formation of brittle intermetallic phaseδ-MoNi at the grain boundary is avoided.Meanwhile,the grain growth of Mo is also effectively inhibited in the sintering process.However,the addition of iron reduces the degree of densification of alloy since the activation effect of Ni is superior to that of Fe.From the experimental results,it could be concluded that the maximum hardness and bending strength are achieved by 95Mo-1.5Ni-3.5Fe alloy,which are HV 614 and 741 MPa,respectively.Combined with the analyses of bending fracture mechanism,the improvement relative to Mo-Ni alloy is likely attributed to the inhibition of the brittle phase.
文摘Hot roll bonding was carried out between commercially pure titanium TA2 and high-strength low-alloy steel Q390 using pure Nb or Mo interlayer at 950 ~C with a total reduction ratio of 86.7%. Interfacial microstructure and bonding properties of titanium clad steel plates were investigated by electron microscopy and mechanical tests. The results showed β-Ti, TiC and Fe2Ti reaction phases were generated at Ti/steel interface for the clad plates with no interlayer. Inserting Nb or Mo interlayer can effectively suppress the formation of brittle phases, while the weak bonding joint transferred to Nb/steel or Mo/steel interface. And some micro-voids were found at the interface of Nb/steel and Mo/steel. The improved shear strength of clad plates with Nb interlayer might be attributed to the elimination of brittle phases at bonding interface. The small size and little quantities of the micro-voids at Nb/steel interface had a relatively weak effect on shear strength. However, the large number and big size of micro-voids were responsible for the degradation of shear strength for the clad plates with Mo interlayer.
