采用表面机械研磨技术在低碳钢上制备出纳米结构表层, 利用 X 射线衍射和电子显微分析研究表层的结构特征, 并对硬度沿厚度方向的变化进行分析. 结果表明: 经过表面机械研磨处理后, 样品表层的晶粒可细化至纳米量级. 表面纳米晶层的厚度约为 40 µm, 平均晶粒尺寸由 10 nm 逐渐增加到 100 nm; 在距表面约 40–80 µm 的深度为亚微晶层, 平均晶粒尺寸进一步增至 1000 nm. 与样品的心部相比, 表层的硬度显著提高

A nanostructured surface layer was fabricated on a low carbon steel plate by using a surface mechanical attrition (SMA) treatment. The refined microstructure in the surface layer was characterized by means of X-ray diffraction and electron microscopy, and the hardness variation along the depth of the treated sample was examined. Experimental evidences show that after the SMA treatment the microstructure of the surface layer may be refined into the nanoscale. The thickness of the nanocrystalline layer is approximately 40 μm and the average grain size increases from 10 nm in the top surface gradually to 100 nm at a depth of 40 μm. In the region of 40-80 μm deep from the top surface, there exists a ultrafine grained layer, in which the average size from 100 nm to about 1000 nm. The hardness of nanostructured surface layer is enhanced significantly after the SMA treatment compared with that of the original sample.