The stainless Fe-Mn-Si shape memory alloy(SMA) coating was prepared on the surface of AISI 304 stainless steel. The principal residual stress measured by the mechanical hole-drilling method indicates that the Fe-Mn-Si...The stainless Fe-Mn-Si shape memory alloy(SMA) coating was prepared on the surface of AISI 304 stainless steel. The principal residual stress measured by the mechanical hole-drilling method indicates that the Fe-Mn-Si SMA cladding specimen possesses a lower residual stress compared with the 304 stainless steel cladding specimen. The mean stress values of the former and the latter on 10-mm-thick substrate are 4.751 MPa and 7.399 MPa, respectively. What's more, their deformation values on 2-mm-thick substrate are about 0° and 15°, respectively. Meanwhile, the variation trend and the value of the residual stress simulated by the ANSYS finite element software consist with experimental results. The X-ray diffraction(XRD) pattern shows ε-martensite exists in Fe-Mn-Si SMA coating, which verifies the mechanism of low residual stress. That's the γ→ε martensite phase transformation, which relaxes the residual stress of the specimen and reduces its deformation in the laser cladding processing.展开更多
Fe-Mn-Si-Cr-Ni composite powders are utilized to form a functional shape memory alloy cladding layer （SMACL） using a laser cladding method. The microstructure, microhardness, and phase composition of the SMACL are m...Fe-Mn-Si-Cr-Ni composite powders are utilized to form a functional shape memory alloy cladding layer （SMACL） using a laser cladding method. The microstructure, microhardness, and phase composition of the SMACL are measured, and the extent of deformation of the laser cladding samples is determined. The SMACL is composed of planar, cellular, and dendritic crystals, equiaxed grains, and oxides with increasing distance from the substrate surface. The SMACL is further composed of ε-martensite and γ-austenite phases, while the tempered SMACL consists mainly of γ-austenite. Extensive deformation occurs in AISI 304 stainless steel laser cladding samples. By contrast, limited deformation is observed in the SMACL samples.展开更多
基金supported by the Fundamental Research Funds for the Central Universities of China(No.3132016354)
文摘The stainless Fe-Mn-Si shape memory alloy(SMA) coating was prepared on the surface of AISI 304 stainless steel. The principal residual stress measured by the mechanical hole-drilling method indicates that the Fe-Mn-Si SMA cladding specimen possesses a lower residual stress compared with the 304 stainless steel cladding specimen. The mean stress values of the former and the latter on 10-mm-thick substrate are 4.751 MPa and 7.399 MPa, respectively. What's more, their deformation values on 2-mm-thick substrate are about 0° and 15°, respectively. Meanwhile, the variation trend and the value of the residual stress simulated by the ANSYS finite element software consist with experimental results. The X-ray diffraction(XRD) pattern shows ε-martensite exists in Fe-Mn-Si SMA coating, which verifies the mechanism of low residual stress. That's the γ→ε martensite phase transformation, which relaxes the residual stress of the specimen and reduces its deformation in the laser cladding processing.
基金supported by the Research Fund for the Doctoral Program of Higher Education of China(No.20122125120013)the Dalian Science and Technology Fund(No.2011J21DW003)the Fundamental Research Funds for the Central Universities(Nos.3132013060 and 3132013311)
文摘Fe-Mn-Si-Cr-Ni composite powders are utilized to form a functional shape memory alloy cladding layer （SMACL） using a laser cladding method. The microstructure, microhardness, and phase composition of the SMACL are measured, and the extent of deformation of the laser cladding samples is determined. The SMACL is composed of planar, cellular, and dendritic crystals, equiaxed grains, and oxides with increasing distance from the substrate surface. The SMACL is further composed of ε-martensite and γ-austenite phases, while the tempered SMACL consists mainly of γ-austenite. Extensive deformation occurs in AISI 304 stainless steel laser cladding samples. By contrast, limited deformation is observed in the SMACL samples.
