The Cr_(7)C_(3)−CrSi_(2)−Al_(2)O_(3)composite coatings were prepared by plasma spraying Cr_(7)C_(3)−CrSi_(2)−Al_(2)O_(3)and Al−Cr2O3−SiC composite powders,respectively.The microstructure,formation mechanism and proper...The Cr_(7)C_(3)−CrSi_(2)−Al_(2)O_(3)composite coatings were prepared by plasma spraying Cr_(7)C_(3)−CrSi_(2)−Al_(2)O_(3)and Al−Cr2O3−SiC composite powders,respectively.The microstructure,formation mechanism and properties of the two Cr_(7)C_(3)−CrSi_(2)−Al_(2)O_(3)composite coatings obtained by plasma spraying were investigated,and the reaction mechanism of the Al−Cr_(2)O_(3)−SiC system was explored.The results show that the coating obtained by plasma spraying Al−Cr_(2)O_(3)−SiC composite powders had thinner lamella and more tortuous interlayer interface,and the in-situ synthesized Cr_(7)C_(3),CrSi_(2) and Al_(2)O_(3) in the coating were all nano-crystallines.Compared with the Cr_(7)C_(3)−CrSi_(2)−Al_(2)O_(3)coating prepared by plasma spraying Cr_(7)C_(3)−CrSi_(2)−Al_(2)O_(3)composite powders,the plasma-sprayed Cr_(7)C_(3)−CrSi_(2)−Al_(2)O_(3)coating obtained from Al−Cr_(2)O_(3)−SiC composite powders had higher density,higher microhardness(increased by 20%),better fracture toughness and lower wear rate(reduced by 28%).展开更多
基金the National Natural Science Foundation of China(No.52072110)the Natural Science Foundation of Hebei Province,China(No.E2018202034).
文摘The Cr_(7)C_(3)−CrSi_(2)−Al_(2)O_(3)composite coatings were prepared by plasma spraying Cr_(7)C_(3)−CrSi_(2)−Al_(2)O_(3)and Al−Cr2O3−SiC composite powders,respectively.The microstructure,formation mechanism and properties of the two Cr_(7)C_(3)−CrSi_(2)−Al_(2)O_(3)composite coatings obtained by plasma spraying were investigated,and the reaction mechanism of the Al−Cr_(2)O_(3)−SiC system was explored.The results show that the coating obtained by plasma spraying Al−Cr_(2)O_(3)−SiC composite powders had thinner lamella and more tortuous interlayer interface,and the in-situ synthesized Cr_(7)C_(3),CrSi_(2) and Al_(2)O_(3) in the coating were all nano-crystallines.Compared with the Cr_(7)C_(3)−CrSi_(2)−Al_(2)O_(3)coating prepared by plasma spraying Cr_(7)C_(3)−CrSi_(2)−Al_(2)O_(3)composite powders,the plasma-sprayed Cr_(7)C_(3)−CrSi_(2)−Al_(2)O_(3)coating obtained from Al−Cr_(2)O_(3)−SiC composite powders had higher density,higher microhardness(increased by 20%),better fracture toughness and lower wear rate(reduced by 28%).