Laser cladding is a novel surface modification technology with significant social and economic value, and it belongs to the category of green manufacturing technologies.
Technological Impact: Laser cladding technology features rapid cooling (up to 10⁶ K/s), low dilution rate (generally less than 5%), strong metallurgical bonding with the substrate, low heat input and distortion, small heat-affected zone, flexible material selection, a wide range of cladding layer thicknesses (0.2~2.0 mm for a single pass), and ease of automation. These characteristics enable the production of fine-grained structures or new phases while preserving the original excellent properties of the cladding material.
Economic Impact: Laser cladding technology is a highly economical new technology that can prepare high-performance alloy surfaces on inexpensive metal substrates without affecting the properties of the substrate, reducing costs and saving precious and rare metal materials. Statistics show that in 2022, the sales volume of laser cladding equipment in China was approximately 12,500 units, and the industry investment scale grew to 2.4 billion yuan. Compared to replacing parts with new ones, laser remanufacturing technology can achieve a utilization rate of over 70% for core components of scrapped equipment, and the comprehensive mechanical properties of the repaired parts are no less than 90% of the original parts.
Environmental Benefits: Laser cladding is a green manufacturing technology that can replace traditional high-energy-consuming and high-polluting electroplating processes (such as hard chrome plating). For example, laser-clad brake discs can significantly reduce particulate matter emissions by more than 80%.
Current Challenges and Future Directions: Laser cladding technology still faces challenges related to the instability of the cladding layer quality, which may result in defects such as porosity, cracks, deformation, and surface unevenness. Cracking sensitivity and automated control remain challenges. The easy cracking of the coating-substrate interface, the need for complex post-processing of repaired parts, long cycles, and high costs are also problems. Future research directions include process parameter optimization, intelligent online monitoring, the construction of digital twin platforms, and the synergy between additive and subtractive manufacturing.