钢基表面单道激光熔覆Fe3Al金属间化合物的研究

以纯Fe3Al粉末为原料,采用同步送粉式激光熔覆工艺在低碳钢基体表面合成Fe3Al金属间化合物.利用金相显微镜、扫描电镜与X衍射实验方法对熔覆合金层、合金层与钢基体的结合界面等进行了显微组织与相结构的分析.结果表明,激光熔覆功率对合金层品质有较大影响,本实验在2 kW激光熔覆功率条件下获得了致密、无肉眼可见气孔、夹杂、裂纹等缺陷的熔覆层,熔覆表面有一定起伏的合金层,合金层与基体间完全冶金结合;熔覆合金层主要由单相Fe3Al构成,熔覆层组织为细小等轴状晶粒,等轴晶内部由大量更为细小的条状Fe3Al晶粒构成.

Study of Single Track Laser Cladding Fe3Al Intermetallic on the Steel Base

The layers of Fe_3Al Intermetallic are prepared on the substrate of steel by single track laser cladding with powders of Fe_3Al. The microstructure and phase constitution of the layers are studied with methods of SEM, EDX and X-Ray analysis technique. The results show the value of cladding power quite influence the layers quality. The compact coatings jointed metallurgically with the steel are obtained when P=2kW, no pore, no inclusion and cracks in macroscopic. The microstructure of the layer consists of equiaxed grain-groups, which consist of large amount of banding fine Fe_3Al grains.