铝合金表面激光熔覆 Fe- Al青铜合金层的组织结构

Microstructure of the Laser Clad Fe Al Bronze Coating on Aluminium Alloy Substrate

研究了铝合金表面激光熔覆 Ｆｅ Ａｌ青铜层的组织结构， 结果表明， 熔覆层的组织结构为孪晶结构的 α Ｃｕ＋ 颗粒状（ Ｃｕ， Ｆｅ， Ｓｉ）９ Ａｌ４ （γ１ ）＋ 少量的 Ｃｕ３ Ａｌ（β）， 硬质点相强化、孪晶强化、细晶强化和固溶强化的共同作用使得熔覆层的维氏硬度达到了 ３ ０００ Ｍ Ｐａ～３ ５００ Ｍ Ｐａ， 明显高于其名义硬度 １ ８００ Ｍ Ｐａ～２ １００ Ｍ Ｐａ。同时， 分析了熔覆层相结构的形成原因。

The microstructure of a laser clad Fe Al bronze coating on an Al alloy substrate has been investigated. The results show that the structure of the coating is twinned α Cu with twin structure, pellet like aluminide (Cu, Fe, Si) 9Al 4( γ 1 ) and a small amount of aluminide Cu 3Al( β ). The microhardness of the laser clad coating (3 000 MPa^3 500 MPa)is much higher than that of the alloy. This significant hardening effect is contributed to the formation of hard phases, the twin ned structure, fine grains and pronounced solid solution strengthening. The reason for the formation of the observed structures in the clad is also discussed.