In this study, the formation, microstructure, and wear properties of Colmonoy 88 (Ni-17W-15Cr-3B-4Si wt.%) + Stellite 1 (Co-32Cr-17W wt.%) coating layers fabricated by high-velocity oxygen fuel (HVOF) spraying are investigated. Colmonoy 88 and Stellite 1 powders were mixed at a ratio of 1:0 and 5:5 vol.%. HVOF sprayed selffluxing composite coating layers were fabricated using the mixed powder feedstocks. The microstructures and wear properties of the composite coating layers are controlled via a high-frequency heat treatment. The two coating layers are composed of γ-Ni, Ni3B, W2B, and Cr23C6 phases. Co peaks are detected after the addition of Stellite 1 powder. Moreover, the WCrB2 hard phase is detected in all coating layers after the high-frequency heat treatment. Porosities were changed from 0.44% (Colmonoy 88) to 3.89% (Colmonoy 88 + ST#1) as the content of Stellite 1 powder increased. And porosity is denoted as 0.3% or less by inducing high-frequency heat treatment. The wear results confirm that the wear property significantly improves after the high-frequency heat treatment, because of the presence of wellcontrolled defects in the coating layers. The wear surfaces of the coated layers are observed and a wear mechanism for the Ni-based self-fluxing composite coating layers is proposed.

Abstract
1. 서 론
2. 실험 방법
3. 결과 및 고찰
    3.1 HVOF Ni계 자용성 복합 코팅 소재의 미세조직
    3.2 HVOF Ni계 자용성 복합 코팅 소재의 경도 특성
    3.3 HVOF Ni계 자용성 복합 코팅 소재의 마모 특성
4. 결 론
References

• 위동열(인하대학교 신소재공학과) | Dong-Yeol Wi (Department of Materials Science & Engineering, Inha University)
• 함기수(인하대학교 신소재공학과) | Gi-Su Ham (Department of Materials Science & Engineering, Inha University)
• 박순홍(포항산업과학연구원) | Sun-Hong Park (Research Institute of Industrial Science & Technology)
• 이기안(인하대학교 신소재공학과) | Kee-Ahn Lee (Department of Materials Science & Engineering, Inha University) Corresponding Author