感应等离子球化Sm_2Zr_2O_7粉末涂层性能研究

The Research on the Properties of Sm_2Zr_2O_7 Powder Prepared by Induction Plasma Spheroidization

采用感应等离子球化技术对喷雾干燥制备的Sm_2Zr_2O_7(SZO)团聚粉末进行了球化处理,通过正交实验研究了各个工艺参数对于粉体球化率的影响,采用大气等离子喷涂技术制备了SZO涂层,利用场发射扫描电镜、X射线衍射(XRD)研究了Sm_2Zr_2O_7粉末及涂层的微观组织形貌、相结构。结果表明,经过感应等离子球化处理后,Sm_2Zr_2O_7粉末呈表面光洁、致密的实心球状,粉末的流动性能提高了67.6%,松装密度提高了128.8%,粉末相结构没有发生变化。各个工艺参数对于Sm_2Zr_2O_7粉末球化率的影响显著性顺序为:氢气流量、氩气流量、反应室压力、送粉速率。所制备的SZO热障涂层各个界面结合紧密,各层致密度较高,孔隙率约为7.54%,结合强度为43.5MPa。

The agglomerated Sm_2Zr_2O_7(SZO) powders were treated by induction plasma spheroidization process and applied as powder of thermal barrier coating(TBC) by atmospheric plasma spraying(APS).The orthogonal design method was used to optimize the parameters of the spheroidization process.Microstructures and phase of SZO powder and TBCs before and after treatment were examined by scanning electrical microscopy and X-ray diffraction(XRD).The results show that the spheroidized Sm_2Zr_2O_7 powders are solid spheres with smooth and dense surface,suitable for atmospheric plasma spraying.No phase transformation occurred after spheroidization treatment.And the flowability and apparent density of SZO powder were increased by 67.6%and 220%,respectively.According to the spheroidization rate of Sm_2Zr_2O_7 powder,the significant degree of parameters in turn is the hydrogen flow rate,argon flow rate,reaction chamber pressure and feeding speed.The SZO coating has compact microstructure and high bonding strength between the topcoat and the bondcoat.The bonding strength and porosity of the coating are about 43.5MPa and 7.54%,respectively.