Low alloying Mg-2 Gd-0.5(Cu/Ni)alloys for sealing tools in the oil and gas industry were prepared.The differences in the effects of minor Cu and Ni additions on microstructures and properties of the Mg-2 Gd alloy were...Low alloying Mg-2 Gd-0.5(Cu/Ni)alloys for sealing tools in the oil and gas industry were prepared.The differences in the effects of minor Cu and Ni additions on microstructures and properties of the Mg-2 Gd alloy were compared.The results showed that adding Ni was more effective than adding Cu in refining grain sizes,strengthening the basal fiber texture,and promoting the formation of LPSO phases,resulting in higher strength.The tensile yield strength/elongation of the Mg-2 Gd-0.5 Cu alloy,Mg-2 Gd-0.25 Cu-0.25 Ni alloy,and Mg-2 Gd-0.5 Ni alloy was 146 MPa/23.7%,175 MPa/23.1%,and 248 MPa/18.2%,respectively.The decreased elongation was attributed to the basal fiber texture and the presence of coarse LPSO phases.In terms of the corrosion rate in 3.5 wt.%NaCl solution,it rose from 112 mm y^(-1)for the Mg-2 Gd-0.5 Cu alloy to 269 mm y^(-1)for the Mg-2 Gd-0.25 Cu-0.25 Ni alloy and 490 mm y^(-1)for the Mg-2 Gd-0.5 Ni alloy,indicating that the addition of Ni instead of Cu showed a more significant promoting effect on the degradability of Mg alloys,which was related to more refined grains,the stronger basal fiber texture,and a larger amount of LPSO phases.展开更多
基金financially supported by the National Key Research and Development Program of China(No.2019YFC1520303)the Scientific and Technological Research Program of Chongqing Municipal Education Commission(No.KJQN202001527)the Natural Science Foundation of Zhejiang Province(No.LQ18E010003)。
文摘Low alloying Mg-2 Gd-0.5(Cu/Ni)alloys for sealing tools in the oil and gas industry were prepared.The differences in the effects of minor Cu and Ni additions on microstructures and properties of the Mg-2 Gd alloy were compared.The results showed that adding Ni was more effective than adding Cu in refining grain sizes,strengthening the basal fiber texture,and promoting the formation of LPSO phases,resulting in higher strength.The tensile yield strength/elongation of the Mg-2 Gd-0.5 Cu alloy,Mg-2 Gd-0.25 Cu-0.25 Ni alloy,and Mg-2 Gd-0.5 Ni alloy was 146 MPa/23.7%,175 MPa/23.1%,and 248 MPa/18.2%,respectively.The decreased elongation was attributed to the basal fiber texture and the presence of coarse LPSO phases.In terms of the corrosion rate in 3.5 wt.%NaCl solution,it rose from 112 mm y^(-1)for the Mg-2 Gd-0.5 Cu alloy to 269 mm y^(-1)for the Mg-2 Gd-0.25 Cu-0.25 Ni alloy and 490 mm y^(-1)for the Mg-2 Gd-0.5 Ni alloy,indicating that the addition of Ni instead of Cu showed a more significant promoting effect on the degradability of Mg alloys,which was related to more refined grains,the stronger basal fiber texture,and a larger amount of LPSO phases.