Sui Qi, Hu Ning, Su Yingrui, Wang Yan, Song Xiaolei
Key Laboratory of Advanced Structural Materials, Ministry of Education, School of Materials Science and Engineering, Changchun University of Technology, Changchun 130012, China.
Micromachines (Basel). 2023 Oct 30;14(11):2017. doi: 10.3390/mi14112017.
The Ni60-SiC-CeO strengthening layer with deep remelting pools was constructed on the surface of 7075 aluminum alloy using the laser remelting-cladding processing method, and a soft and hard interphase was prepared on the matrix by the interval of laser remelting, which was inspired by soft-hard interphase structure with excellent crack inhibition performance from the natural world. The microstructure and microhardness of the remelting region and the remelting-cladding region of the strengthening layer were studied. The tensile characteristics of two distinct strengthening layers were investigated in the laboratory. The results showed that the grain size of remelting pools is finer, and the microhardness is higher than that of the matrix, which makes crack propagation more difficult. In addition, the results show that the strengthening layer has compact and flawless microstructure and has been metallurgically integrated with the matrix, and the microhardness of the regions treated by laser cladding and laser remelting-cladding has been improved obviously. Toughness has improved, as has the problem of toughness reduction after cladding ceramic particles. The sample's strength is also significantly greater than that of the untreated sample.
采用激光重熔包覆加工方法,在7075铝合金表面构建了具有深熔池的Ni60-SiC-CeO强化层,并通过激光重熔间隔在基体上制备了软硬相间的界面,这一灵感来源于自然界中具有优异裂纹抑制性能的软硬相间结构。研究了强化层重熔区和重熔包覆区的微观组织和显微硬度。在实验室中研究了两种不同强化层的拉伸特性。结果表明,熔池的晶粒尺寸更细,显微硬度高于基体,这使得裂纹扩展更加困难。此外,结果表明强化层具有致密无缺陷的微观组织,并且与基体实现了冶金结合,激光包覆和激光重熔包覆处理区域的显微硬度明显提高。韧性得到了改善,包覆陶瓷颗粒后韧性降低的问题也得到了解决。样品的强度也明显高于未处理样品。