Advantages of Laser Technology - Breakthrough High-Strength Steel Processing Technology

Automakers are increasingly relying on laser technology for the processing of high-strength steel. Whether for welding, cutting, or surface treatment, the economic advantages of laser processing are further demonstrated. High-strength steel is being used more widely in the automotive industry, which further reduces manufacturing costs. This is because the use of high-strength steel reduces the number of components in the assembly process, thereby lowering production costs, reducing the overall weight of the vehicle, and ultimately decreasing fuel consumption. Laser cladding application - surface wear-resistant treatment The use of new steel materials is not without obstacles. To achieve high-strength or ultra-high-strength performance, automotive components are typically subjected to pressure hardening during the forming process. The "CoolTool" project conducted by the Institute of Molding and Forming at Graz University of Technology in Austria is focused on this area of research. This program includes a mold processing system for low-temperature tempering of the pressure hardening process, utilizing improved technology to economically pressure harden boron alloy steel. The geometry of the cooling channels is network-like throughout the mold, optimizing cooling and heating capabilities and shortening processing cycles. Molds are typically made from ductile cast iron, which is low-cost and easy to machine, but has issues such as low surface strength and poor wear resistance. Therefore, it is necessary to coat high-load areas with a layer of high-hardness material, which can be accomplished through laser powder cladding. It has been proven that laser powder cladding is an excellent method for completing this process. Trumpf Laser Systems has also conducted research on this process and developed Direct Metal Deposition (DMD) equipment. In this process, metal powder is fed into the laser melt pool on the workpiece surface in a coaxial direction with the laser beam, without the need for preheating the workpiece. The metal powder forms a high-strength wear-resistant metallurgical mixture with the base material. Compared to traditional sintering methods, laser powder deposition has unparalleled advantages: low heat input, increased hardness, and reduced surface cracking; limited hardness distribution within the coating, good friction coefficient; minimal deformation of the base material, and residual stress during forming does not lead to cracking. Moreover, laser powder deposition can be fully utilized in automated production. 3D laser cutting - an irreplaceable method Edge trimming is another challenge for high-strength steel. 3D laser cutting is suitable for trimming formed sheet metal parts, especially for steel plates with strengths up to 1500 MPa, as there are no alternative processing methods. In this case, users do not need to invest in expensive stamping and cutting equipment. This is because the lifespan of traditional equipment's dies or tools is significantly shortened when processing these high-hardness materials, while laser cutting does not have to consider these issues and also has advantages such as short installation time and flexible product or sample production. Trumpf's 3D laser product TruLaserCell has been applied to the cutting of the B-pillar of the Volkswagen Passat, including edge trimming. The B-pillar is made from hot-formed high-strength steel, which has high hardness and must withstand significant stress. The B-pillar made from high-strength steel increases impact resistance and enhances vehicle safety. This is also why, despite the higher cost of high-strength steel, automakers are still willing to use it. Laser welding - efficiency, flexibility, economy Laser can be used for both cutting high-strength steel and welding. Laser welding is more efficient, more economical, and significantly improves welding quality. However, laser welding requires higher precision, and the investment cost of lasers is relatively high.