Research On The Microstructure And Property Of AgCuNi/Cu Noble-base Metal Composite Material

AgCuNi/Cu noble-base metal composite material was used extensively due to their good wear-resiting property and electrical conductivity. In this study, AgCuNi/Cu noble-base metal composite materials’noble metal alloy claddings’metallographical structures were researched and analyzed by means of scanning electronic microscope and microhardness tester. On this basis, noble metal alloy claddings’micro-frictional wear property were researched and analyzed by means of micro-friction wear testing machine, and the frictional behaviors were analyzed by means of metallographical structures. Noble metal alloy claddings’incipient wear was simulated by nano-test instrument. The micro-abrasive dusts’shape and the relationship with macro-abrasive dusts were researched and analyzed. The main research results as follows:(1) AgCuNi/Cu noble metal alloy claddings’basal phases are allα-Ag(but the basal phases of AgCu4PdNi0.3 was Ag-Pd solid solution), the second-phases are all banded structures, the number of the second-phases was determined by the content of the element. When other conditions were the same, the more Cu element in the noble metal alloy claddings, the more second-phases created . The hardness of tested materials was affected remarkably by second-phases’number and distribution in the noble metal alloy claddings.(2) the main wear way between AgCuNi and AgPd30 noble metal alloy claddings are all adhesion wear. Surface abrasion was expressed by AgCu4Ni0.3 noble metal alloy cladding under low-load, and the small flakes were generated; work-hardening layers and adhesive transfer layers were expressed by AgCu4Ni0.3 noble metal alloy claddings under high-load, and the bigger flakes were generated. The abrasive dust of AgCu3ZnNi0.3 is not obvious, the work-hardening layers generated in the frictional wear can reduce friction coefficient. Grainy abrasive dusts were generated in AgCu6ZnNi0.3 noble metal alloy cladding, while grainy and flaky abrasive dusts were generated in AgCu4PdNi0.3 noble metal alloy cladding. Because of the outermost layer and the second layer alloys interacted each other, three-layer noble-base metallic composites’noble metal alloy claddings have good wear-resiting property and low friction coefficient. Part materials of the noble metal alloy claddings’were transferred to the AgPd30 surface. And then the abrasive dusts generated by adhesion wear taking part in grinding abrasion.(3) Plastometric set was generated under the load on the surface of noble metal alloy cladding. When the plastometric set cumulated to a certain extent, cracks were generated in a certain depth of the surface or in the original inherent vice, and then the early micro-abrasive dusts were generated by the crack extension under the load. The different early incipient wear of noble metal alloy cladding lead to different micro-frictional wear.