Friction And Wear Properties Of Bronze Alloy Powder Coatings

Cu-14A1-X material 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 of contrastive friction property of the laser cladding coatings and the plasma spray welding coatings of bronze alloy power,witch made based on Cu-14A1-X alloy,with RFT-Ⅲfriction machine to promote Cu-14Al-X alloy to use in the field of surface engineering.The structure of the laser cladding coatings and the plasma spray welding coatings of bronze powder have been studied by SEM,XRD and EPMA.The results show that the influence of the preparation on coatings' morphology,composition and hardness significantly.Firstly,the laser cladding coatings and the plasma spray welding coatings have the same phase,they were composed byα+γ2+β'+ K phase. but their morphology are very different.The microstructure of the laser cladding coatings are uniform and dense,and the K phase uniform dispersed in the grain.The size of the K phase of the plasma spray welding coatings are more larger than the laser cladding coatings,and it's distributing unequally.Secondly,the laser cladding coatings' component of Fe element is 11.30%,but the plasma spray welding coatings of Cu-14A1-X's component of Fe element is only 3.83%.Thirdly,the surface hardness of the laser cladding coatings are much higher than the plasma spray welding coatings.The surface hardness of the laser cladding coatings have reached 43.88HRC,and the laser cladding coatings' surface hardness only 28.51HRC.Three conclusions can be drawn by doing friction experiment with RFT-Ⅲfriction machine under boundary lubrication.Firstly,the laser cladding coatings and the plasma spray welding coatings' friction mechanism are very different.The laser cladding coatings' abrasion mechanism is mostly abrasive wear,but the plasma spray welding coatings' abrasion format is minor abrasive wear under low load,and the abrasion format will change to serious adhesion wear with the load increased,at the same time,accompanied with abrasive wear.Secondly,the plasma spray welding coatings shows excellent friction properties at low-load condition.But the plasma spray welding coatings' friction coefficient and wear amounts were increased intensely at high load,it's stability of frictional properties is not as well as the laser cladding coatings.The friction properties of coatings and Cu-14A1-X alloy were compared,the results show that,firstly,the abrasion mechanism of the Cu-14A1-X alloy is same as the laser cladding coatings,is mostly abrasive wear,but the plasma spray welding coatings' chief abrasion format is adhesion wear.Secondly,the plasma spray welding coatings' friction properties are better than the Cu-14A1-X alloy at low load condition.But,the plasma spray welding coatings' friction properties is the worst at the high load.Thirdly,the laser cladding coatings' friction properties is similar to the Cu-14A1-X alloy.The laser cladding coatings' wear amounts slightly larger than the Cu-14A1-X alloy,but it's frictional stability get better.