Fabrication of new type cermets of functionally graded materials with surface of high thermal resistance above 3000℃

一些Cermets; TaC， TaC， ZrC， ZrN， TiC， TiN和Ti-D22-D2 AIN已从金属中制造成功; Ta， Zr， Ti和TiAl， Respectively，根据最初开发的反应性等离子体处理的含义。每个细胞都是在一个亚表面的基础金属制成的，作为碳化物或硝酸盐的厚层。TaC、ZrC和TiC的分解温度，据报道，Sintering生产的温度达到4000、3550和3300 ° C，尊重。等离子体处理在1000摄氏度以上的高温下完成。由于加工温度和加工时间的影响，许多陶瓷元件都增加了。As the results of the preliminary experiment， the maximum Vicker's hardness and thickness of cermets; TaC， ZrC and Ti-D22-D2AIN were 3000 Hv/100-m for 5 h，1300 Hv/100-m for 5 h and 3500 Hv/24-m for 3 h [Hv; kg·mmイイD12イエD1]， respectively.The characteristic features of processed cermets were on the points，（1）在基础金属的亚表面产生的陶瓷金属是指基础金属的转化--它们自身与表面上的碳或硝基差异的辅助作用，（2）修改后的层中碳或硝基化合物的合并概况及其与表面距离的接口。陶瓷层必须具有功能分级的材料在硬度、热条件和修改层上的抗磨损能力的属性;此外，在较低处理温度下，一种带有20 MeV电子束的新处理方法在性能之前进行了等离子体处理，以增加修改层的厚度。The thickness of TaC-？met layer carbonized at 1300？after the irradition to a fluence of 3×10？D115？D1e·cm？D1-2？D1 increased by about four times that of non-irradiation at 1000？。

Some cermets; TaC, TaC, ZrC, ZrN, TiC, TiN and TiィイD22ィエD2AIN have been fabricated successfully from metals; Ta, Zr, Ti and TiAl, respectively, by means of the reactive plasma processing developed originally. Each cermet was formed at a sub-surface of base metal as a thick layer of carbide or nitride. The decomposition temperature of TaC, ZrC and TiC, produced by sintering were reported to reach 4000, 3550 and 3300℃, respectively. The plasma processing was done at high temperature over 1000℃. Thicknesses of cermets were increased with the processing-temperature and the processing-time. As the results of the preliminary experiment, the maximum Vicker's hardness and thickness of cermets; TaC, ZrC and TiィイD22ィエD2AIN were 3000Hv/100μm for 5h, 1300Hv/100μm for 5h and 3500Hv/24μm for 3h [Hv;kg・mmィイD12ィエD1], respectively.The characteristic features of processed cermets were on the points, 1) Cermets were produced at the sub-surface of base metals by means of transformation of base metals-themselves with an aid of carbon or nitrogen diffused from the surface facing the processing plasma, 2) The concentration profile of carbon- or nitrogen-compounds degraded gradually in the modified layer and the interface with the distance from the surface. The cermet layers must have the properties of functionally graded materials on hardness, thermal conductivity and the abrasion resistance of modified layer.Additionally, the new processing with 20MeV-electron beam was performed before the plasma processing for increasing the thickness of modified layer at the lower processing temperature. The thickness of TaC-cermet layer carbonized at 1300℃ after the irradition to a fluence of 3×10ィイD115ィエD1 e・cmィイD1-2ィエD1 increased by about four times that of non-irradiation at 1000℃.