A low-pressure hollow cathode plasma source carburizing was developed as a novel surface treatment technique based on the active screen plasma carburizing combined with hollow cathode sources. The cylindric cathodic cage with array holes was made of pure graphite, where the hollow cathode graphite tubes were inlaid on. A pulsed high voltage power with a peak voltage of 800 V and a pulse frequency of 30 kHz was supplied to ignite the hollow cathode discharge inside graphite tubes at a low pressure less than about 300 Pa using a gas mixture of CH₄ + 90%H₂. The hollow cathode plasma source together with the pulsed high voltage power realized a high biasing current on the carburized samples at low pressure, and produced an enhanced heating except the thermal radiation by the cathodic cage. The graphite cathode as a carbon source besides the gas precursor provided an additional carbon potential. The AISI 304L austenitic stainless steel was carburized at a low temperature of 450 °C for a treatment time of 6 h with a bias of 200 V under the carburizing pressure of 50 Pa and 300 Pa, respectively. It was observed that the carburizing case at 50 Pa was about 13 μm with a higher surface carbon concentration of about 6.5 at.% and a higher hardness of about HV_{0.25 N} 8.5 GPa compared with that at 300 Pa. The carbon-expanded austenite (γ_C) phase was observed by the x-ray diffraction of both the carburizing cases. The metastable high carbon carbide Fe₅C₂ only appeared at 50 Pa, which was attributed to high carbon potential at the lower pressure. Therefore, an increased carburizing efficiency at the low temperature was obtained by the low-pressure hollow cathode plasma source carburizing technique using a pulsed high voltage power.

低压空心阴极等离子源渗碳是在活性屏等离子渗碳与空心阴极源相结合的基础上发展起来的一种新型表面处理技术。带阵列孔的圆柱形阴极笼由纯石墨制成，空心阴极石墨管镶嵌在其上。提供峰值电压为 800 V 和脉冲频率为 30 kHz 的脉冲高压电源，以使用 CH ₄  + 90%H的气体混合物在小于约 300 Pa 的低压下点燃石墨管内的空心阴极放电₂. 空心阴极等离子体源与脉冲高压电源一起在低压下在渗碳样品上实现了高偏置电流，并产生了除阴极笼的热辐射外的增强加热。除了气体前体之外，作为碳源的石墨阴极提供了额外的碳势。AISI 304L奥氏体不锈钢分别在50 Pa和300 Pa的渗碳压力下，在450℃的低温和200 V的偏压下进行渗碳处理时间为6 h。观察到，与 300 Pa的渗碳情况相比，50 Pa 的渗碳情况约为 13 μm，表面碳浓度较高，约为 6.5 at.%，硬度较高，约为 HV _{0.25 N} 8.5 GPa。碳膨胀奥氏体（ γ _C) 相是通过两种渗碳情况的 X 射线衍射观察到的。亚稳态高碳碳化物 Fe ₅ C ₂仅在 50 Pa 时出现，这归因于较低压力下的高碳势。因此，通过使用脉冲高压电源的低压空心阴极等离子体源渗碳技术，在低温下提高了渗碳效率。