Defect-free TiC/Si multi-layer electrical discharge coatings
Defect-free TiC/Si multi-layer electrical discharge coatings
复制标题
DOI：
10.1016/j.matdes.2018.06.019
复制
发表时间：
2018-10
影响因子：
8.4
通讯作者：
J. Murray;R. Cook;N. Senin;S. J. Algodi;A. Clare
中科院分区：
文献类型：
--
作者：
J. Murray;R. Cook;N. Senin;S. J. Algodi;A. Clare
放电涂层（EDC）工艺可用于在保形基材表面沉积硬质材料。下一代电火花加工组件可能会利用附着现象来提高重铸层的性能，从而避免重铸层的移除。在这里，首次开发了一种无裂纹和孔隙的陶瓷基复合层，使用牺牲TiC和Si电极进行顺序涂层。利用硅屑在间隙中加宽放电过程的衰减解释了层性能的改善。WC和TiC的复合镀层具有良好的元素混合性能。附着水平与熔点密切相关，熔点高的材料由于凝固速度更快而不易弹出。纳米压痕显示，TiC和WC/TiC层具有最高的平均硬度值，大约是Cu基加工层的两倍，其硬度为11.0 GPa，远高于基体的1.9 GPa。
The process of electrical discharge coating (EDC) may be used to deposit hard materials on conformal substrate surfaces. Next generation EDM'd components may exploit attachment phenomena to enhance recast layer properties, to avoid the need for recast layer removal. Here, a ceramic based composite layer was developed without cracking and porosity for the first time, using sequential coating using sacrificial TiC and Si electrodes. Attenuation of the discharge process by gap widening using Si debris in the gap explained improved layer properties. Composite coatings combining WC and TiC were also demonstrated, with good elemental intermixing. Attachment level was correlated strongly with melting point, with high melting point materials resisting ejection due to more rapid solidification. Nanoindentation showed the TiC and WC/TiC layers possessed the highest mean hardness values, approximately double that of the Cu based machined layer which itself yielded a much higher hardness of 11.0 GPa compared to 1.9 GPa of the substrate.