| Fe-Cr-Mo系的激光表面合金化 | |
| 王俊 | |
| Subtype | 硕士 |
| Thesis Advisor | 斯重遥 |
| 1988 | |
| Degree Grantor | 中国科学院金属研究所 |
| Place of Conferral | 中国科学院金属研究所 |
| Abstract | 为了提高材料表面的性能，尤其是耐蚀性，研究了中碳低合金钢上铬钼喷涂层的激光表面合金化工艺、显微组织结构和性能之间的关系。建立了扫描速度与熔化深度、宽度、熔化面积的关系，认为熔化面积与扫描速度之间的关系更能体现激光的熔化效果；在激光合金化过程中合金元素要发生烧损，在一定的范围内烧损量随扫描速度的增大而增加，而且铬的烧损量比钼的高。通过各种实验守段研究了显微组织、成分均匀性、显微硬度、表面裂纹和热疲劳性能。3Cr18Mo6合金层中存在大量的块状奥氏体。激光处理完全抑制或大大减少了X相、σ相、碳化物的析出，激光处理还改变了碳化物的类型。激光处理对耐蚀性有很大的影响。3Cr18Mo6在1N H_2SO_4中的耐蚀性比18-8不锈钢的好，在含Cl~-离子的介质中没有发生点蚀，具有优异的耐点蚀性能。 |
| Other Abstract | Laser surface alloying of Cr Mo plasma-sprayed steel was investigated in an effort to modify material's surface properties, especially corrosion resistance. The relationships among scanning rate, melted depth, melted width and melted area were established, it was pointed out that the relationship between scanning rate and melted area could express the laser melting effect better. Alloy elements were evaporated and lost in laser surface alloying. At a certain power density, the loss of alloy elements increased with the increase of scanning rate in a certain range of scanning rate, besides, the loss of Cr was more than that of Mo. The microstructure of alloyed layers, composition uniformity, microhardness, surface crack, thermal fatigue were studied by various experiments. Large amount of austenite was retained in laser alloyed Fe-18%Cr-6%Mo layer. X-phase, σ-phase and carbides were eliminated or reduced by laser treatment, types of carbides were also changed by laser treatment. Electrical chemical experiment results showed that laser treatment affected corrosion behaviour greatly. The corrosion resistance of Fe-18%Cr-6%Mo in 1N H_2SO_4 was better than that of 18-8 stainless steel and the alloy layer had no pitting in the solution containing Cl~-. Therefore, laser alloyed Fe-18%-6%Mo have excellent corrosion resistance especially pitting resistance and could be used in many fields. |
| Pages | 58 |
| Language | 中文 |
| Document Type | 学位论文 |
| Identifier | http://ir.imr.ac.cn/handle/321006/17331 |
| Collection | 中国科学院金属研究所 |
| Recommended Citation GB/T 7714 | 王俊. Fe-Cr-Mo系的激光表面合金化[D]. 中国科学院金属研究所. 中国科学院金属研究所,1988. |
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