Infuence Of Fe On Microstructure And Hardess Of Aluminum Bronze Powder Plasma Spray Coating

The bronze alloy has been developed successfully by our group, it has been applied to make stamping die successfully for it's good performance for example high strength,excellent plastic,wear resistance and wear corrosive.The paper studied microstructure and property of the bronze alloy power which made based on the bronze alloy and infuence of Fe on microstructure and hardess of aluminum bronze powder plasma spray coatings which was prepared on various substrates (45steel, ZQA19-4 alloy and T3 copper) by plasma spray technique in order to further apply in the field of surface engineering.The bronze alloy power and the plasma spray welding coatings have been studied by SEM,XRD,EDSand EPMA,etc. The results indicated that:Firstly, the bronze alloy powder by atomization has good sphericity, smooth surface structure, good density and particle size distribution. Secondly,bulk density of -300 purpose aluminum bronze alloy powder is maximum,-200～+300 purpose alloy powder has the best liquid. thirdly,45 steel substrate,ZQA19-4 alloy substrate and T3 copper substrate aluminum bronze powder coatings are composed of a solid solution (white),βsolid solution (gray) and K-phase (black) which is distributed in a substrate,a-phase is Cu-based substitution solid solution,βcontain a andγphase (black),γphase is Cu9Al4-based intermediate solid solution, K-phase is mainly intermetallic compound AlFe,AlFe3 and Fe3Mn7,etc. Fourth, phases of power and three different substrate coatings are Cu9Al4,AlFe3,AlFe and Fe3Mn7. Fifth,45 steel substrate,ZQA19-4 alloy substrate and T3 copper substrate plasma spray coatings and substrates are metallurgy bonding.45 steel substrate sprayed coating has a wider metallurgy bonding district,and ZQA19-4 alloy substrate and T3 copper substrate plasma spray coatings have a narrower metallurgy bonding district. Sixth, formation of aluminum bronze powder plasma spray coating has characteristic of rapid solidification, microstructure of the organization also has characteristic of rapid solidification. Seventh, diffusion of element Fe on aluminum-bronze alloy spray welding layer has a major impact。45 steel substrate sprayed coating have more dendritics and serious intragranular composition segregation,and ZQA19-4 alloy substrate and T3 copper substrate coatings have smaller dendrites.Macro-hardness and micro-hardness of the bronze alloy power and the plasma spray welding coatings have been tested in HBRV-187.5 Brinell Rockwell Vickers hardness tester and HX-1000TM digital micro hardness tester. The results indicated that:Firstly, micro-hardness of the bronze alloy powder by atomization is higher, with an average hardness value of 542.17HV. Among them, the dark gray or black block has a higher hardness value, hardness of white matrix phase is lower. secondly, three different substrate coatings hardness generally fluctuates from 300HV to 400HV. ZQA19-4 alloy substrate and 45 steel substrate coatings hardness peak lies in the binding layer, T3 copper substrate coating hardness peak lies in the spray layer. Thirdly, diffusion of element Fe on aluminum-bronze alloy spray welding layer has a certain impact to coatings hardness.45 steel substrate coating macro-hardness is minimum, T3 copper substrate macro-hardness coating is maximum.