Nanostructured (NS) W-Cu composite powder was prepared by mechanical alloying (MA), and nanostructured bulk of W-Cu contact material was fabricated by hot pressed sintering in an electrical vacuum furnace. The mic...Nanostructured (NS) W-Cu composite powder was prepared by mechanical alloying (MA), and nanostructured bulk of W-Cu contact material was fabricated by hot pressed sintering in an electrical vacuum furnace. The microstructure, electric conductivity, hardness, breakdown voltage and arcing time of NS W-Cu alloys were measured and compared to conventional W-Cu alloys prepared by powder metallurgy. The results show that microstructural refinement and uniformity can improve the breakdown behavior, the electric arc stability and the arc extinction ability of nanostructured W-Cu contacts materials. Also, the nanostructured W-Cu contact material shows the characteristic of spreading electric arcs, which is of benefit to electric arc erosion.展开更多
Microstructure of W-Cu alloy wire before and after hot-swaging was studied in this paper. Results show that a homogeneous microstructure of the W-Cu alloy wire was formed after hot-swaging treatment, and the tungsten ...Microstructure of W-Cu alloy wire before and after hot-swaging was studied in this paper. Results show that a homogeneous microstructure of the W-Cu alloy wire was formed after hot-swaging treatment, and the tungsten particles were embedded in copper phases to form a networking structure;the W-Cu alloy wire has a microstructure of body-centered-cubic tungsten particles and face-centered-cubic copper phase, and did not change after hot-swaging. The intermediate phases have not been found during the process, but the size of the tungsten particles in the copper matrix becomes smaller. After hot-swaging, the treated W-Cu alloy wire has a relative density of 105.1%, and a conductivity of 47.2% IACS, the tensile and bending strength can be as large as 644 and 1600 MPa, respectively.展开更多
基金supported by the National Natural Science Fundation of China under grant No.50071043the Natural Science Fundation of Shaanxi province under grant No.2004E105.
文摘Nanostructured (NS) W-Cu composite powder was prepared by mechanical alloying (MA), and nanostructured bulk of W-Cu contact material was fabricated by hot pressed sintering in an electrical vacuum furnace. The microstructure, electric conductivity, hardness, breakdown voltage and arcing time of NS W-Cu alloys were measured and compared to conventional W-Cu alloys prepared by powder metallurgy. The results show that microstructural refinement and uniformity can improve the breakdown behavior, the electric arc stability and the arc extinction ability of nanostructured W-Cu contacts materials. Also, the nanostructured W-Cu contact material shows the characteristic of spreading electric arcs, which is of benefit to electric arc erosion.
文摘Microstructure of W-Cu alloy wire before and after hot-swaging was studied in this paper. Results show that a homogeneous microstructure of the W-Cu alloy wire was formed after hot-swaging treatment, and the tungsten particles were embedded in copper phases to form a networking structure;the W-Cu alloy wire has a microstructure of body-centered-cubic tungsten particles and face-centered-cubic copper phase, and did not change after hot-swaging. The intermediate phases have not been found during the process, but the size of the tungsten particles in the copper matrix becomes smaller. After hot-swaging, the treated W-Cu alloy wire has a relative density of 105.1%, and a conductivity of 47.2% IACS, the tensile and bending strength can be as large as 644 and 1600 MPa, respectively.