HVOF和APS喷涂制备掺杂超细Al_(2)O_(3)颗粒复合CoNiCrAlY涂层研究

Study on Composite CoNiCrAlY Coating with Super Fine Al_(2)O_(3) Particles Sprayed by HVOF and APS

在MCrACY中添加一定量Al_(2)O_(3)可提高其高温磨损性能。为此,将CoNiCrAlY和微米级Al_(2)O_(3)粉末颗粒按比例混合后在密封球磨机里球磨,筛分后得到复合CoNiCrAlY/Al_(2)O_(3)粉末颗粒。分别采用超音速火焰(HVOF)喷涂和大气等离子(APS)喷涂制备复合CoNiCrAlY/Al_(2)O_(3)涂层,并对喷涂粉末及2种涂层的形貌及性能进行了分析表征。SEM分析显示粉末颗粒内部含弥散分布的超细Al_(2)O_(3)颗粒。2种方式制备的涂层都含有弥散分布的超细Al_(2)O_(3)颗粒。HVOF制备的涂层中保留超细Al_(2)O_(3)颗粒较好。APS制备的涂层中超细Al_(2)O_(3)颗粒有所减少,涂层层间形成大量层状氧化物。2种方式制备的涂层中,HVOF制备的涂层硬度、结合强度高。

Adding a certain amount of Al_(2)O_(3) to MCrACY could improve its high temperature wear resistance.For this,CoNiCrAlY and micron Al_(2)O_(3) powder particles were mixed in proportion and then milled in a sealed ball mill to obtain composite CoNiCrAlY/Al_(2)O_(3) powder particles after sieving.Then,composite CoNiCrAlY/Al_(2)O_(3) coating was sprayed by HVOF and APS,respectively,and the morphologies and properties of two coatings were investigated.SEM results showed that both composite powder and coatings prepared by two methods had the dispersed super fine Al_(2)O_(3) particles inside the particle.The coating prepared by HVOF had better retention of ultrafine Al_(2)O_(3) particles.However,the ultra-fine Al_(2)O_(3) particles in APS coating were reduced,and a large number of layered oxides were formed between the coatings.Comparison of the coatings prepared by the two methods showed that HVOF coatings had larger hardness and higher bonding strength.