The microstructure and melting properties of ternary Ag-Cu-In intermediate-temperature alloys （400-600 ℃） prepared by electric arc melting were investigated in this work. The melting properties, phase compositions,...The microstructure and melting properties of ternary Ag-Cu-In intermediate-temperature alloys （400-600 ℃） prepared by electric arc melting were investigated in this work. The melting properties, phase compositions, microstructure and hardness were charac- terized by differential scanning calorimetry （DSC）, X-ray diffraction （XRD）, scanning electron microscopy （SEM） and micro-hardness tester, respectively. The results show that the melting properties, phase compositions, microstructure and hardness of Ag-Cu-In brazing alloys are substantially different when adding different levels of indium. Indium element could effectively reduce the melting temperatures of （Ag-Cu28）-xIn alloys, and the melting temperatures of （Ag-Cu28）-25In alloy are located at 497.86 and 617.48 ℃. When the indium content varies from 5 wt% and 10 wt%, the dominant phases in the alloys are Ag-rich and Cu-rich phases, and their granular crystals are smaller than 0.5 ktm. When the indium content is higher than 15 wt%, the phase compositions of the alloy are Ag4In and Cu11In9, and the microstructure exhibits dendritic crystals with a uniform distribution. The hardness of （Ag- Cu28）-xIn alloy decreases first and then increases with the content of indium increasing, and the highest hardness of （Ag-Cu28）-25In alloy is HV 266.0.展开更多
The nanowire and whisker heterostructures of tin dioxide were fabricated by the chemical vapor deposition technique.It was demonstrated that various structures of tin oxide can be obtained by controlling the thickness...The nanowire and whisker heterostructures of tin dioxide were fabricated by the chemical vapor deposition technique.It was demonstrated that various structures of tin oxide can be obtained by controlling the thickness of gold layer and the partial pressure of source vapor at growing sites.12.5 and 25 nm thicknesses are preferable for the epitaxial growth of nanowires and heterostructure through vapor–liquid–solid mechanism,respectively.The tin dioxide whiskers with core-shell structure were fabricated by vapor–solid mechanism.Meanwhile,the influences of various factors on the tin dioxide growth are also discussed.展开更多
基金financially supported by the Open Project of State Key Laboratory Cultivation Base for Nonmetal Composites and Functional Materials(No.11zxfk13)the Scientific Research Fund of Sichuan Provincial Education Department(No.14ZB0103)the China Scholarship Council(CSC)
文摘The microstructure and melting properties of ternary Ag-Cu-In intermediate-temperature alloys （400-600 ℃） prepared by electric arc melting were investigated in this work. The melting properties, phase compositions, microstructure and hardness were charac- terized by differential scanning calorimetry （DSC）, X-ray diffraction （XRD）, scanning electron microscopy （SEM） and micro-hardness tester, respectively. The results show that the melting properties, phase compositions, microstructure and hardness of Ag-Cu-In brazing alloys are substantially different when adding different levels of indium. Indium element could effectively reduce the melting temperatures of （Ag-Cu28）-xIn alloys, and the melting temperatures of （Ag-Cu28）-25In alloy are located at 497.86 and 617.48 ℃. When the indium content varies from 5 wt% and 10 wt%, the dominant phases in the alloys are Ag-rich and Cu-rich phases, and their granular crystals are smaller than 0.5 ktm. When the indium content is higher than 15 wt%, the phase compositions of the alloy are Ag4In and Cu11In9, and the microstructure exhibits dendritic crystals with a uniform distribution. The hardness of （Ag- Cu28）-xIn alloy decreases first and then increases with the content of indium increasing, and the highest hardness of （Ag-Cu28）-25In alloy is HV 266.0.
基金supported by Deakin University under a postgraduate research scholarship,the Fundamental Scientific Research Funds for Chinese Academy of Tropical Agricultural Sciences (Nos.1630022011033 and 1630062013011)the Natural Science Foundation of Hainan Province,China (No.20155197)
文摘The nanowire and whisker heterostructures of tin dioxide were fabricated by the chemical vapor deposition technique.It was demonstrated that various structures of tin oxide can be obtained by controlling the thickness of gold layer and the partial pressure of source vapor at growing sites.12.5 and 25 nm thicknesses are preferable for the epitaxial growth of nanowires and heterostructure through vapor–liquid–solid mechanism,respectively.The tin dioxide whiskers with core-shell structure were fabricated by vapor–solid mechanism.Meanwhile,the influences of various factors on the tin dioxide growth are also discussed.
