Korean Institute of Surface Engineering

pISSN : 1225-8024 | eISSN : 3399-8403


한국표면공학회지 (39권4호 179-189)

HVOF Thermal Spray Coating of WC-Co for Durability Improvement of High Speed Spindle

초고속 스핀들의 내구성 향상을 위한 WC-Co 분말의 HVOF 용사 코팅

Kim, K.S.;Baek, N.K.;Yoon, J.H.;Cho, T.Y.;Youn, S.J.;Oh, S.K.;Hwang, S.Y.;Chun, H.G.;

창원대학교 나노신소재 공학부;(주)써머텍코리아;대구기계부품연구원;포항산업과학연구원;울산대학교;
School of Nano Advanced Materials Engineering, Changwon National University;Sermatech Korea Co., LTD;Daegu Machinery Institute of Components & Materials;Mater. & Processes Research Center, Research Institute of Industrial Science & Technology;School of Materials Science & Engineering, University of Ulsan;


High velocity oxygen fuel(HVOF) thermal spray coating of WC-Co powder is one of the most promising candidate for the replacement of the traditional hard chrome plating and ceramics coating because of the environmental problem of the very toxic $Cr^{6+}$ known as carcinogen and the brittleness of ceramics coating. WC-Co micron and nano powder were coated by HVOF thermal spraying method for the study of durability improvement of the high speed spindle. Coatings were planned by Taguchi program for the four spray parameters of spray distance, flow rates of hydrogen, oxygen and powder feed rate. Optimal coating process was obtained by the studies of coating properties such as porosity, surface roughness, micro hardness, and micro structure. WC-Co micron and nano powder were coated on the Inconel 718 substrate by the optimal coating process obtained in this study. The wear behaviors were studied by the sliding wear tester at room temperature and at an elevated temperature of $500^{circ}C$ for the application to high speed spindle. Sliding wear test was carried out for four most promising hard coatings of chrome coating, ceramics coatings such as $A1_2O_3,;Cr_2O_3$ and HVOF Co-alloy T800 for the comparison of their wear behaviors. HVOF WC-Co coating was better than other coatings showing highest micro hardness of 1400 Hv and comparable friction coefficients with others. HVOF WC-Co coating is a strong candidate for the replacement of the traditional hard chrome plating for the high speed spindle.


WC-Co;Wear resistance;Thermal spraying;HVOF;High speed spindle;