Ren Sendong, Shen Yihao, Wang Taowei, Chen Hao, Ma Ninshu, Yang Jianguo
College of Mechanical Engineering, Zhejiang University of Technology, Hangzhou 310014, China.
Joining and Welding Research Institute, Osaka University, Osaka 567-0047, Japan.
Polymers (Basel). 2025 Apr 7;17(7):997. doi: 10.3390/polym17070997.
In the present research, laser circle welding (LCW) was proposed to join dual-phase steel (DP980) and carbon fiber-reinforced plastic (CFRP). The welding appearance, cross-section of the welded joint and fracture surfaces were subjected to multi-scale characterizations. Joining strength was evaluated by the single-lap shear test. Moreover, a numerical model was established based on the in-house finite element (FE) code JWRIAN-Hybrid to reproduce the thermal process of LCW. The results showed that successful bonding was achieved with a laser power higher than 300 W. The largest joining strength increased to about 1353.2 N (12.2 MPa) with 450 W laser power and then decreased under higher heat input. While the welded joint always presented brittle fracture, the joining zone could be divided into a squeezed zone (SZ), molten zone (MZ) and decomposition zone (DZ). The morphology of CFRP and chemical bonding information were distinct in each subregion. The chemical reaction between the O-C=O bond on the CFRP surface and the -OH bond on the DP980 sheet provided the joining force between dissimilar materials. Additionally, the developed FE model was effective in predicting the interfacial maximum temperature distribution of LCW. The influence of laser power on the joining strength of LCW joints was dualistic in character. The joining strength variation reflected the competitive result between joining zone expansion and local bonding quality change.
在本研究中，提出采用激光环切焊接（LCW）工艺来连接双相钢（DP980）和碳纤维增强塑料（CFRP）。对焊接外观、焊接接头横截面和断口表面进行了多尺度表征。通过单搭接剪切试验评估连接强度。此外，基于内部有限元（FE）代码JWRIAN-Hybrid建立了数值模型，以再现LCW的热过程。结果表明，当激光功率高于300W时可实现成功焊接。在450W激光功率下，最大连接强度提高到约1353.2N（12.2MPa），然后在更高的热输入下降低。虽然焊接接头总是呈现脆性断裂，但连接区可分为挤压区（SZ）、熔化区（MZ）和分解区（DZ）。每个子区域中CFRP的形态和化学键合信息都不同。CFRP表面的O-C=O键与DP980板材上的-OH键之间的化学反应提供了异种材料之间的连接力。此外，所开发的有限元模型能够有效地预测LCW的界面最高温度分布。激光功率对LCW接头连接强度的影响具有双重性。连接强度的变化反映了连接区扩展和局部粘结质量变化之间的竞争结果。
