Wang Wen-Jing, Li Jia-Hui, Liu Xue-Feng, Bai Yu-Liang
Beijing Laboratory of Metallic Materials and Processing for Modern Transportation, University of Science and Technology Beijing, Beijing 100083, People's Republic of China.
Institute for Advanced Materials and Technology, University of Science and Technology Beijing, Beijing 100083, People's Republic of China.
Langmuir. 2023 Aug 22;39(33):11797-11806. doi: 10.1021/acs.langmuir.3c01524. Epub 2023 Aug 9.
To improve the interfacial bonding of dissimilar composites, the interaction mechanism between the surface state and severe plastic deformation to strengthen the interfacial bonding strength was revealed. In this study, the different surface states of the steel strip were designed by louver blade grinding (LBG) and diamond bowl grinding (DBG), and the cold-rolled composite method was developed to prepare the brass/carbon steel composite strips. The results show that the steel surface after DBG has a large roughness of 9.79 μm, a hard hardening layer of 6.2 GPa, and high cleanliness of 1.34 atomic % oxygen content, while that after LBG has a roughness of 1.31 μm, a hardening layer of 4.2 GPa, and an oxygen content of 2.37 atomic %. The large roughness promotes the breaking of the hardening layer; the hardening layer is beneficial to obtain sufficient interfacial stress to expose the fresh metal; and the high cleanliness reduces the barrier to the fresh metal and contributes to the bonding of the fresh metal. The interface of the cold-rolled brass/carbon steel composite strip after LBG and DBG is mechanical bonding and metallurgical bonding, respectively. In the process of the cold-rolling composite, large shear deformation occurs at the interface of brass and steel, resulting in a high concentration of vacancy and dislocation defects, which provides a channel for interdiffusion of atoms at the interface. Under the diffusion driving force provided by the cold-rolling shear deformation heat, a nanodiffusion layer with a thickness of 60 nm and high interfacial bond strength was formed.
为提高异种复合材料的界面结合性能，揭示了表面状态与剧烈塑性变形之间的相互作用机制以增强界面结合强度。在本研究中，通过百叶窗叶片磨削（LBG）和金刚石碗磨削（DBG）设计了钢带的不同表面状态，并开发了冷轧复合方法来制备黄铜/碳钢复合带材。结果表明，DBG处理后的钢表面粗糙度为9.79μm，硬化层硬度为6.2GPa，氧含量为1.34原子%，具有较高的清洁度；而LBG处理后的钢表面粗糙度为1.31μm，硬化层硬度为4.2GPa，氧含量为2.37原子%。较大的粗糙度促进了硬化层的破碎；硬化层有利于获得足够的界面应力以暴露新鲜金属；高清洁度降低了新鲜金属的扩散障碍，有助于新鲜金属的结合。LBG和DBG处理后的冷轧黄铜/碳钢复合带材界面分别为机械结合和冶金结合。在冷轧复合过程中，黄铜和钢的界面处发生了较大的剪切变形，导致空位和位错缺陷高度集中，为界面处原子的相互扩散提供了通道。在冷轧剪切变形热提供的扩散驱动力作用下，形成了厚度为60nm、界面结合强度高的纳米扩散层。
