Abstract: By using plasma arc method a copper base alloy surfacing weld was formed on steel Q235,with Sn P bronze powder with nickel base alloy powder.The microstructures of surfacing weld and bond area have been studied by means of optical metallography,SEM and XRD.Hardness and wear resistance of the surfacing weld bave been measured.The result shows that the bond between surfacing weld and base metal is metallurgical bond,and bond line is clear.Surfacing wled has a low rate of dilution.The surfacing weld with copper base alloy DGCu150 consists of α-Cu phase,δ phase,ε phase,Cu₃P.The surfacing weld with copper base alloy DGCu150+ nickel base alloy DGNi50A consists of α-Cu phase,δ phase,ε phase,Cu₃P,γ-Ni,Ni₂B,CrB,(Fe,Ni)₂₃C₆,(Cu,Ni)₂₃C₆ and Fe₅Si₂B₂.As the increasing of nickel base alloy powder,the thickness of bond area increases and hardness and wear vesistanee of the surfacing weld improved greatly.