Wang Lixin, Jiang Xinyu, Yang Guang, Dong Shiyun, Yan Shixing
Hebei University of Science and Technology, Shijiazhuang, People's Republic of China.
Academy of Armored Force Engineering, Beijing, People's Republic of China.
R Soc Open Sci. 2025 Jun 4;12(6):241980. doi: 10.1098/rsos.241980. eCollection 2025 Jun.
The damage to brake discs in heavy-duty vehicles caused by uneven wear is usually repaired with milling method, which reduces their radius and accordingly shortens their service life. Laser cladding repair can maintain the radius, thereby gradually becoming a promising method for brake disc repair, but the complexity of the laser cladding process causes the cladding layer to generate defects that decrease the repair quality. Here, we studied the regulation mechanism of laser power, beam diameter and scanning speed in the cladding layer's quality via simulation and experiment. Simulation results showed that with the increase of laser power and the decrease of beam diameter or scanning speed, the molten pool's temperature and flow rate, and the cladding layer's residual stress have varying degrees of increase. We then fabricated laser cladding samples (Ni60/WC on ductile iron) and acquired their micromorphology, dilution rate and microhardness, and analyzed their regulation mechanism. Experiment results exhibited that the cladding process with laser power 1400 W, beam diameter 3 mm and scanning speed 10 mm/s can make the cladding layer have a better quality. This study provides an available reference for the laser cladding repair of uneven wear in brake discs from heavy-duty vehicles.
重型车辆制动盘因磨损不均造成的损坏通常采用铣削方法修复，这会减小其半径，从而缩短其使用寿命。激光熔覆修复能够保持半径，因此逐渐成为一种很有前景的制动盘修复方法，但激光熔覆过程的复杂性会导致熔覆层产生缺陷，降低修复质量。在此，我们通过模拟和实验研究了激光功率、光束直径和扫描速度对熔覆层质量的调控机制。模拟结果表明，随着激光功率的增加以及光束直径或扫描速度的减小，熔池的温度和流速以及熔覆层的残余应力都有不同程度的增加。然后我们制备了激光熔覆样品（球墨铸铁上的Ni60/WC）并获取了它们的微观形貌、稀释率和显微硬度，并分析了其调控机制。实验结果表明，激光功率1400W、光束直径3mm、扫描速度10mm/s的熔覆工艺可使熔覆层具有较好的质量。本研究为重型车辆制动盘磨损不均的激光熔覆修复提供了有用的参考。
