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本文讨论了脉冲式真空渗碳的工艺过程及其主要特点。 采用内热式冷壁真空炉研究了真空渗碳的各个工艺参数──渗碳时间、渗碳温度、渗碳期炉内压力、扩渗比（扩散期时间与渗碳期时间之比）等──对渗碳效果的影响，并根据试验结果提出一些初步看法。 真空渗碳的速度比普通气体渗碳快４倍，渗碳层的表面含碳量可以通过改变扩渗比得到调整。真空渗碳的质量明显地优于普通气体渗碳。 一般渗碳工艺（指气体渗碳等）的缺点是生产周期过长，渗碳质量不够理想（如经常有异常组织，表面碳浓度控制也不够准确等）。用冷壁内热式真空炉进行真空渗碳，允许采用较高的渗碳温度，使渗碳速度大大加快。在质量上，真空渗碳完全避免了各种异常组织，使渗碳零件的性能有了明显的提高。 本文在进行了一些试验的基础上对真空渗碳的特点、工艺过程、各工艺参数的影响等问题做了初步的探讨。
This article discusses the pulsed vacuum carburizing process and its main features. The various parameters of vacuum carburizing - carburizing time, carburizing temperature, pressure in carburizing furnace, expansion ratio (ratio of diffusion time to carburizing time), etc., were studied by means of internal heat type cold wall vacuum furnace. ─ The effect of carburizing effect, and based on the test results put forward some preliminary views. Vacuum carburizing 4 times faster than ordinary carburizing carburized surface carbon content can be adjusted by changing the expansion ratio. The quality of vacuum carburizing is obviously superior to ordinary carburizing. General carburizing process (gas carburizing, etc.) the disadvantage is the long production cycle, carburizing quality is not ideal (such as often have abnormal tissue, the surface carbon concentration control is not accurate enough, etc.). Vacuum wall carburizing with a vacuum furnace in a cold wall allows the carburizing temperature to be higher and the carburising speed to be considerably faster. In terms of quality, vacuum carburizing completely avoids all kinds of abnormal structure, so that the performance of carburized parts has been significantly improved. In this paper, based on some experiments on the characteristics of vacuum carburizing, process, the impact of various process parameters made a preliminary discussion.