摘要
采用扫描电镜、电子探针、X射线衍射和透射电镜技术分析了氧乙炔火焰喷焊WC增强镍基自熔性合金复合涂层的组织结构,并采用湿砂橡胶轮式磨粒磨损试验机对该涂层与等离子喷涂NiCr/Cr3C2涂层的磨损性能进行了实验比较。结果表明,复合喷焊层内形成了-γNi固溶体基体,其中弥散分布着大量细小的碳化物硬质相Cr3C2、B4C、Cr7C3、Cr23C6等。WC颗粒仅在边缘处发生部分溶解,与涂层基体形成了冶金结合,周围生成针状的碳化铬枝晶。该组织决定了喷焊层基体具有较高的硬度,WC增强颗粒与基体之间具有很高的结合强度。复合喷焊层具有很好的耐磨粒磨损性能,其磨损失重量仅为NiCr/Cr3C2涂层的57%。
Microstructure of WC reinforced Ni-based self-fluxing alloy composite coating prepared by oxy-acetylene flame spray-welding was investigated by scanning electron microscopy (SEM), electron probe micro-analysis (EPMA), X-ray diffraction (XRD) and transmission electron microscopy (TEM). The wear performance of the coating and plasma sprayed NiCr/Cr3C2 coating were tested by a MLS-225 wet sand rubber wheel abrasive wearing tester. The results indicate that γ-Ni solid solution forms as matrix, in which large amounts of fine carbide grains such as Cr3C2, B4 C, Cr7C3, Cr23C6 disperse. WC grains partly dissolve at the edge and metallurgically bond with coating matrix. Needle-like chromium carbide dendrites form around WC grains. The structure gives hard matrix and high binding strength of WC grain and matrix. The coating shows excellent wear resistance and its weight loss is only 57 percent of that of NiCr/Cr3C2 coating.
出处
《材料热处理学报》
EI
CAS
CSCD
北大核心
2006年第3期116-120,共5页
Transactions of Materials and Heat Treatment
关键词
磨损
喷焊
涂层
镍基自熔性合金
Acetylene
Coatings
Microstructure
Scanning electron microscopy
Solid solutions
Transmission electron microscopy
Wear resistance
Welding
X ray diffraction analysis
