Comparative studies of the microstructure, porosity and hardness of the surface layer of a low-carbon steel are performed after nitrocarburizing by traditional single-cycle and novel multi-cycle treatments. The sizes and the content of pores in the surface layer are determined, the profile of the variation of microhardness over its thickness is plotted, and an x-ray diffraction analysis is performed. It is recommended to use multi-cycle nitrocarburizing for surface treatment of parts from low-carbon steels in order to raise the operating characteristics of the parts.

中文翻译：

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多循环氮碳共渗对低碳钢组织和表面硬度的影响

通过传统的单循环和新型的多循环处理，对低碳钢表面层的组织、孔隙率和硬度进行了对比研究。确定表面层中孔的大小和含量，绘制显微硬度随其厚度变化的曲线，并进行 X 射线衍射分析。低碳钢零件的表面处理建议采用多循环氮碳共渗，以提高零件的操作特性。