新型Fe-Cu复合材料的设计及性能研究

Design and Properties of New Fe-Cu Composites

基于粉末冶金液相烧结技术对Fe-Cu复合材料进行结构设计,以尺寸均匀呈密排方式的Fe合金球为强化相,其间隙以熔融态Cu进行填充形成导电树枝结构,通过调整Fe和Cu的比例制备出新型Fe-Cu合金;为进一步达到强化作用,对Fe合金进行成分设计,使其能通过淬火进行强化。采用真空热压液相烧结技术制备出Fe-Cu复合材料,优化制备工艺,研究铜含量、导电树枝尺寸对导电率和力学性能的影响,进一步分析强韧化热处理工艺对材料组织和力学性能的影响,在此基础上进行了初步的高速载流摩擦磨损性能试验。研究表明:含50%Cu复合材料的导电率能达到31%IACS,抗拉强度达到457 MPa;对含37%Cu的复合材料进行强韧化处理,调质后铁基组织为回火索氏体, Fe和Cu界面结合良好,抗拉强度为588 MPa,导电率达到20%IACS以上;高速载流摩擦磨损试验表明,随Fe-Cu合金强度的提高其磨损抗力显著增加。

A new Fe-Cu composite was designed based on the powder metallurgy liquid-phase sintering technology. The Fe alloy balls with uniform size and dense arrangement were used as the strengthening phase, and the gaps of Fe alloy were filled with molten Cu to form the conductive branched structure. A novel Fe-Cu alloy was prepared by adjusting the weight ratio of Fe and Cu. In order to achieve the better strengthening, the composition of Fe alloy was designed to be strengthened by quenched treatment. The Fe-Cu composites were prepared by vacuum hot pressing liquid-phase sintering technology. The effects of copper content, conductive branch size on electrical conductivity and mechanical properties were investigated, the influence of strengthening and toughening heat treatment process on the microstructure and mechanical properties of the material was further analyzed, and the preparation process was optimized. On this basis, a preliminary high-speed tribological test with electric current was carried out. The research showed that the conductivity of the composites containing 50%Cu could reach 31%IACS and the tensile strength was 457 MPa. The composite material containing 37%Cu was toughened and treated, after quenching and tempering, the iron-based structure was tempered Sorbite, and the interface between Fe and Cu was well bonded. The tensile strength was 588 MPa and the electrical conductivity was above 20% IACS. The high-speed current-carrying wear test revealed that the wear resistance was significantly improved due to the increase of the strength of the Fe-Cu alloy.