TiA1双层辉光离子渗Cr的工艺研究

利用双层辉光离子渗金属技术（DGPSAT）对TiAl金属间化合物进行渗Cr处理。研究了主要工艺参数对渗层表面合金含量CA和渗层厚度δ这两个目标函数的影响。结果表明,表面合金含量CA和渗层厚度δ随源极电压Vs、有效功率密度比κ的增加而增加;随阴极电压Vc的增加而减少。气压存在一个峰值,太高或太低都不利。工艺参数的最佳值:源极电压Vs为1200V～1300V,阴极电压为200V～300V,有效功率密度比κ为4～5,气压为25Pa～30Pa。

Processing of Double Glow Plasma Chromising on TiAl Intermetallics

Chromising treatment of TiAl intermetallics was conducted by double glow plasma (DGPSAT). Effects of key processing parameters on two objective functions of alloy concentration CA on diffusion coating surface and thickness 8 of diffusion coating were investigated. Experimental results indicated that alloy concentration CA on surface and thick-ness S of diffusion coating increased with source pole voltage Vs and valid power density ratio K and decreased with cath-ode voltage Vc. There is a peak in gas pressure, and it will be unfavorable if the value is too high or too low. The optimal values of key process parameters are as follows: source pole voltage Vs is 1 200 V ~ 1 300 V, cathode voltage Vc is 200 V ~ 300 V, valid power density ratio K is 4 ~ 5 and gas pressure is 25 Pa ~ 30 Pa.