J. Mater. Sci. Technol. ›› 2007, Vol. 23 ›› Issue (04): 525-528.

• 论文 • 上一篇    下一篇

Influence of Surface Nano-structured Treatment on Pack Boriding of H13 Steel

徐凌云;吴晓春;汪宏斌   

  1. 上海大学
  • 收稿日期:2006-11-13 修回日期:2007-04-29 出版日期:2007-07-28 发布日期:2009-10-10
  • 通讯作者: 徐凌云

Influence of Surface Nano-structured Treatment on Pack Boriding of H13 Steel

Lingyun XU, Xiaochun WU, Hongbin WANG   

  1. School of Materials Science and Engineering, Shanghai University, Shanghai 200072, China
  • Received:2006-11-13 Revised:2007-04-29 Online:2007-07-28 Published:2009-10-10
  • Contact: Xiaochun WU

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摘要： 为了降低热作模具钢H13的渗硼温度，在渗硼之前对试样进行表面机械研磨处理，使其表面晶粒尺寸达到纳米级。渗硼过程中主要考虑的工艺参数为温度与时间。通过TEM、SEM、XRD技术和硬度试验研究了纳米化表面的晶粒尺寸，热稳定性，渗硼层厚度，表面形貌以及相组成。同时还对原始面以及纳米化面的渗硼动力学进行了分析对比。结果表明，预先表面机械研磨处理后，形成的硼化物层更厚，并且硬度梯度更为平缓。此外，在700℃下进行8小时固体渗硼后，在纳米化表面形成5μm左右的渗硼层，层中的相为Fe2B相。渗硼动力学研究表明表面纳米化后渗硼激活能明显降低。

关键词: 渗硼, 表面机械研磨处理, H13钢, 渗硼动力学

Abstract: In order to lower the boriding temperature of hot work steel H13, method of surface mechanical attrition treatment (SMAT), which can make the grain size of the surface reach nano-scale, was used before pack boriding. The growth of the boride layer was studied in a function of boriding temperature and time. By TEM (transmission electron microscopy), SEM (scanning electron microscopy), XRD (x-ray diffraction) and microhardness tests, the grain size, thermal stability of the nano-structured (NS) surface and the thickness, appearance, phases of the surface boride layer were studied. Kinetic of boriding was compared between untreated samples and treated samples. Results showed that after SMAT, the boride layer was thicker and the hardness gradient was smoother. Furthermore, after boriding at a low temperature of 700℃ for 8 h, a boride layer of about 5 μm formed on the NS surface. This layer was toothlike and wedged into the substrate, which made the surface layer combine well with the substrate. The phase of the boride layer was Fe2B. Research on boriding kinetics indicated that the activation energy was decreased for the treated samples.

Key words: Boriding, Surface mechanical attrition treatment (SMAT), H13 steel, Boriding kinetic