| Author Name | Affiliation | | Xingdong Yuan | School of Materials Science and Engineering, Shandong Jianzhu University, Jinan 250101, China | | Xiaojie Yang | Shandong Institute for Product Quality Inspection, Jinan 250100, China | | Feng Tian | Shandong Quality and Technical Examination Assess Center, Jinan 250014, China | | Bin Xu | School of Materials Science and Engineering, Shandong Jianzhu University, Jinan 250101, China |
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| Abstract: |
| A nanostructured layer was fabricated on the surface of steel Q235 by using fast multiple rotation rolling (FMRR). The Cr-Rare earth-boriding process was carried out followed at different temperatures. Experimental results showed that the thickness of the boride layer was significantly increased by surface nanocrystallization. The morphology of the boride layer was saw-toothed. An uniform, continuous and dense boride layer was obtained and adhered well to the substrate. The penetrating speed of FMRR specimens was enhanced by 1.9,1.7 and 1.5 times when the Cr-Rare earth-boriding temperature was 843, 873 and 923 K. Severe plastic deformation, which grain size was approximately 100 nm, was observed on steel Q235 surface. Mechanism of Cr-Rare earth-boriding was also studied. |
| Key words: nanostructure low temperature steel Q235 boride layer |
| DOI：10.11916/j.issn.1005-9113.15377 |
| Clc Number:O157.5 |
| Fund: |
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| Descriptions in Chinese: |
| 表面纳米化对Q235钢低温硼铬稀土共渗的影响 袁兴栋1，杨晓洁2，田 丰3，许 斌1 （1.山东建筑大学 材料科学与工程学院，济南 250101;2.山东省产品质量检验研究院，济南 250100; 3.山东省质量技术审查评价中心，济南 250014) 创新点说明：1）用快速多重旋转碾压法（FMRR）对Q235钢表面进行预处理； 2）在Q235钢表面实现低温硼铬稀土共渗，共渗温度分别为843K、873K和923K。 研究目的： 1）本文解决了零件表面高温渗硼的不足； 2）零件变形小，共渗层脆性降低，共渗层与基体结合更加牢固。 研究方法： 1）利用快速多重旋转碾压设备对Q235钢表面进行纳米化； 2）利用数字低真空扫描电子显微镜对渗硼层及表面纳米化引起的变形层进行表征，并对渗硼层厚度进行测量； 3）利用透射电子显微镜对高密度位错及纳米结构进行表征。 结果： 1）843 K温度下，渗硼层形态是锯齿状，致密、均匀、连续，与基体结合良好；渗硼层厚度为13μm； 2）873 K温度下，渗硼层形态是锯齿状，致密、均匀、连续，与基体结合良好；渗硼层厚度为19μm； 3）923 K温度下，渗硼层形态是锯齿状，致密、均匀、连续，与基体结合良好；渗硼层厚度为25μm。 结论： 1）表面纳米化使Q235钢渗硼层厚度显著增加，渗速在843 K、873 K和923 K温度下分别提高了1.9倍、1.7倍和1.5倍； 2）表面纳米化使Q235钢表面硬度显著提高。 关键词： 纳米结构;低温;Q235钢; 硼化物层 |
