钢-铜铅合金烧结双金属柱塞缸体的研制

Development of steel copper lead alloy sintering bi metall cylinder block for plunger pump

以４５＃钢为基体，以烧结铜铅合金为摩擦层，研究了双金属结合状态、烧结过程铅析出机理以及提高双金属结合强度和铜铅合金层物理机械性能，避免铅析出、铅偏析的工艺。本研究烧结铜铅合金层组织晶粒细小，铅分布均匀，相对密度９０％以上，抗拉强度≥１５０Ｎ／ｍｍ２，硬度ＨＢ为７０，具有良好的减摩性和耐磨性，双金属结合区为Ｆｅ、Ｃｕ互相扩散的冶金结合，双金属剪切强度≥１２０Ｎ／ｍｍ２。对比试验表明，本研究双金属柱塞缸体性能优于浇铸缸体。

Bi metal cylinder block is made of medium carbon steel base and copper lead alloy as antifrictional layer.The bi metallic bond state and the lead separation mechanism have been analyzed.The improvement of bi metallic bond strength,and method of avoiding lead separation and segregation have been studied.The sintering copper lead alloy layer has fine gain even lead distribution,the relative density above 90%,σ b≥150N/mm 2,and HB≥70.It has excellent antifriction property and wear resistance too.The bi metallic interface,which has τ b≥120N/mm 2,combines metallurgically with Fe and Cu diffusing mutually.The comparative experiment shows that the properties of our bi metal cyinder block are superior to those produced by casting copper alloy.