摘要
BN-SiO-SiAlON composite ceramics were successfully prepared by the means of hot pressed sintering.Xe plasma flow generated by HallThruster was used for sputtering the surface of the samples in order to evaluate the plasma erosion resistance.XRD,TEM,SEM,and LSCM were used to characterize the phase composition and morphologies of as-made composite ceramics before and after Xe plasma erosion.The ceramics were composed of h-BN,fused silica,and SiAlON,which maintained structuralstability during the process of Xe plasma sputtering.In conclusion,comparing with BN-SiOcomposite ceramics,the plasma erosion rate of BN-SiO-SiAlON composite ceramics decreases significantly at first then rises with the increase of AlN addition.Erosion pits can be observed by using SEM on the surface after plasma sputtering,which demonstrates that the BN grains have dropped off the surface.In addition,mechanicaldenudation by high-speed Xe ions is recognized as the injury mechanism for the BN-matrix composite materials.
BN-SiO_2-SiAlON composite ceramics were successfully prepared by the means of hot pressed sintering.Xe plasma flow generated by HallThruster was used for sputtering the surface of the samples in order to evaluate the plasma erosion resistance.XRD,TEM,SEM,and LSCM were used to characterize the phase composition and morphologies of as-made composite ceramics before and after Xe plasma erosion.The ceramics were composed of h-BN,fused silica,and SiAlON,which maintained structuralstability during the process of Xe plasma sputtering.In conclusion,comparing with BN-SiO_2 composite ceramics,the plasma erosion rate of BN-SiO_2-SiAlON composite ceramics decreases significantly at first then rises with the increase of AlN addition.Erosion pits can be observed by using SEM on the surface after plasma sputtering,which demonstrates that the BN grains have dropped off the surface.In addition,mechanicaldenudation by high-speed Xe ions is recognized as the injury mechanism for the BN-matrix composite materials.
基金
Funded by the National Natural Science Funds for Distinguished Young Scholar(No.51225203)
the National Natural Science Foundation of China(Nos.51372050 and 50902030)
