钢的等离子体基低能离子注入的传质机制

等离子体基低能离子注入是一种钢的低温，低压表面改性方法，它包括等离子体源离子渗氮和等离子体源离子渗碳两种工艺。等离子体基低能离子注入的主要传质机制是低能离子注入－同步热扩散，即在脉冲负偏压作用下的离子首先完成不依赖于工艺温度的低能离子注入，然后已注入的原子在较低的工艺温度上发生足够的热扩散，等离子体热扩散吸收具有补充的传质作用，但由于工艺温度较低，这种作用很小，连续的热扩散过程有利于改善注入吸收条

MASS TRANSFER MECHANISM FOR PLASMA-BASED LOW-ENERGY ION IMPLANTION OF STEEL

Plasma-based low-energy ion implantation, including plasma source ion nitriding and plasma source ion carburizing, has been emerged as a low-temperature, low-pressure modification approach for steel. In the processes, the low-energy ion implantation and simultaneously thermo-diffusion inward are the major mass transfer mechanism. The low-energy ion implantation was carried out under independent condition on the process temperature. And then the indiffusion of the implanted species was found due to the presence of the temperature field. The plasma thermo-diffusional absorption in between the bias pulses has an additional mass transfer effect, however, the additional contribution which is depended on the process temperature is limited by the process temperatures. Also, in the plasma environment between the bias pulses, the enhanced effects on the mass transfer were observed because the continuous diffusion of the implanted species in the bulk steel led to the condition improvement in the surface absorption and the outward escape of the implanted species was prevented, respectively.