文档介绍：STUDY ON FORMING MECHANISM OF THE Fe-Al2O3-POSITE COATING BY REACTIVE PLASMA SPRAYING
ABSTRACT
Composite powders of Al/Fe2O3 were synthesized by spray granulation method using inexpensive aluminium powder and iron oxide powder. And the metal and posite coating was synthesized by plasma spraying using posite powders of Al/Fe2O3. The microstructure of posite coating was checked and ponent was analyzed. The products of the reaction posite powders were tested. Combined with thermodynamic analysis, the forming mechanism of posite coating was studied.
After mixing the aluminium powder and iron oxide powder, posite powders were synthesized by spray granulation method using the aluminium powder and iron oxide powder. By selecting appropriate ones, posite powders with high intensity, rounded shapes, well-regularity and excellent liquidity, can be used for plasma spraying to synthesize posite coating. The better processing parameter was obtained by orthogonal experiment to improve the process of posite powder synthesize.
By plasma spraying technology, the metal and posite coating was synthesized using posite powders. During the process, posite powders would take reaction at the same time. That would release high energy to let the powders e liquid. The molten powders impacted to the substrate and spread out to form posite coating. posite coating was mainly constituted by FeAl2O4, Fe and Al2O3 was dispersedly embedded in the coating.
In the process of posite coating, there were three periods: the
incubation period, the reaction period and condensation period. By posite powders quenching test, the reaction products were studied. The reaction of posite powders in balance condition was studied by thermodynamics analysis.
bining with the products by actual reaction, the forming mechanism of posite coating can be studied.
KEY WORDS: spray granulation, reactive plasma spraying, metal and posite coating, mechanism of reaction
原创性声明
本人郑重声明:所呈交的学位论文,是本人在导师指导下,进行研究工作所取得的成果。除文中已