Diamond saw blade is made by welding some cutter heads sintered by diamond particles and bonded metal on the steel cutter body. It is widely used in the cutting and processing of non-metallic hard building materials, such as stone processing, building construction, highway and airport runway cutting or seam cutting. The diamond saw blade is composed of a steel base and an arc shaped cutter head, which are joined by sintering, high-frequency welding and laser welding. The welding of diamond saw blade belongs to the welding of dissimilar metals between different materials and different tissues. Among the three joint methods, laser welding is an advanced joint forming method, and the bonding strength of the weld is ideal. The matrix is the support of the diamond saw blade. During sawing, it must withstand strong impact and vibration. Therefore, the matrix material must have high strength, good rigidity, no deformation and erosion resistance. As the base steel of diamond saw blade, it is required not only to have sufficient strength and good plasticity, but also to have high hardenability and thermal stability. In the past, the traditional high-frequency welding saw blade was made of high carbon steel (high carbon tool steel, high carbon low alloy tool steel), such as 65Mn, 70Cr1, SKS5, 50Mn2V or 75Cr steel. These materials are enough to meet the requirements of diamond saw blades and are relatively durable. Low carbon steel is not suitable for laser deep penetration welding. During the rapid heating and cooling process of laser welding, the high carbon steel matrix is prone to crack and fracture. Therefore, high strength low-alloy steel shall be selected as the base material for laser welding, and 28CrMo, 30CrMo and 35CrMo are mainly selected at present. These materials have high strength and toughness, high permeability, good weldability and processability, and the hardness after heat treatment can reach more than 36HRC, which is suitable for laser welding of substrates
