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采用铸渗技术在45钢表面制备了镍基合金渗层,对渗层的微观组织及弯曲行为进行了研究。结果表明:渗层组织致密,与基体呈冶金熔合,在渗层内部及渗层与基体的结合界面处无任何夹杂、气孔及微裂纹等缺陷,渗层主要由镍基固溶体、CrB以及Cr3Ni2组成;带有渗层的试样三点弯曲载荷-位移曲线上出现了三个峰值,在第一个峰值刚出现时渗层表面微裂纹开始萌生,随着第二个峰值的出现微裂纹微量扩展,在第三个峰值发生时渗层宏观断裂,但从载荷位移曲线上发现相同位移条件下其载荷依然大于基体,这说明渗层并没有完全破坏,第三个峰值时的载荷为0.88 kN,较相同条件下基体的载荷提高115%。
Casting infiltration technology was used to prepare Ni-based alloy layer on the surface of 45 steel, and the microstructure and bending behavior of the layer were studied. The results show that the infiltrated layer is compact and metallurgically fused with the substrate. There are no inclusions, pores and micro-cracks in the interface of the infiltrated layer and the interface between the infiltrated layer and the substrate. The infiltrated layer mainly consists of Ni-based solid solution, CrB and Cr3Ni2 . The three-point bending load-displacement curve of the specimen with the coating layer shows three peaks. When the first peak appears, the micro-cracks in the coating surface begin to germinate. As the second peak appears, the micro-cracks expand slightly , The macroscopic fracture at the third peak happened. However, the load was still larger than that of the matrix under the same displacement condition. This indicated that the permeation layer was not completely destroyed, the load at the third peak was 0.88 kN, Compared with the same conditions, the load on the substrate increased by 115%.