The isothermal section at 927 ℃ of the Cr-Ni-Ti system was established using a high-efficiency diffusion couple approach, supplemented with eight equilibrated alloys. The alloy compositions were selected on the basis...The isothermal section at 927 ℃ of the Cr-Ni-Ti system was established using a high-efficiency diffusion couple approach, supplemented with eight equilibrated alloys. The alloy compositions were selected on the basis of the experimental results from the diffusion couple. Both the diffusion couple specimens and the alloys were examined by means of optical microscopy, scanning electron microscopy, and electron probe microanalysis. No ternary compound is found at 927 ℃. The following five three-phase equilibria are well determined: TiNi3+(Cr)+(Ni), TiNi3+(Cr)+TiNi, TiNi+(Cr)+Cr2Ti, Ti2Ni+Cr2Ti+TiNi and Ti2Ni+Cr2Ti+(Ti). The solubilities of Cr in NiTi2, NiTi, and Ni3Ti are determined to be 7.5%, 14.5% and 11.4% (molar percent), respectively. α-Cr2Ti and β-Cr2Ti dissolve about 9.2% and 13.9% Ni (molar percent), respectively.展开更多
基金Project(50425103) supported by the National Science Fund for Distinguished Young Scholars of ChinaProject(50571114) supported by the National Natural Science Foundation of China
文摘The isothermal section at 927 ℃ of the Cr-Ni-Ti system was established using a high-efficiency diffusion couple approach, supplemented with eight equilibrated alloys. The alloy compositions were selected on the basis of the experimental results from the diffusion couple. Both the diffusion couple specimens and the alloys were examined by means of optical microscopy, scanning electron microscopy, and electron probe microanalysis. No ternary compound is found at 927 ℃. The following five three-phase equilibria are well determined: TiNi3+(Cr)+(Ni), TiNi3+(Cr)+TiNi, TiNi+(Cr)+Cr2Ti, Ti2Ni+Cr2Ti+TiNi and Ti2Ni+Cr2Ti+(Ti). The solubilities of Cr in NiTi2, NiTi, and Ni3Ti are determined to be 7.5%, 14.5% and 11.4% (molar percent), respectively. α-Cr2Ti and β-Cr2Ti dissolve about 9.2% and 13.9% Ni (molar percent), respectively.
