35s

优化资料：

The base material of Komatsu excavator bucket teeth is mostly austenitic high-manganese steel (steel grade ZGMn13), therefore, during welding repair, EDMn-B-16 (grade D266) high-manganese steel surfacing welding electrodes are selected. The filler metal of this electrode is austenitic high-manganese steel, and molybdenum is also added to the filler metal, which improves the crack resistance and wear resistance of the weld metal. Therefore, the surfacing welded bucket teeth using this electrode have characteristics of work hardening, high toughness, and good wear resistance on the surface, and the hardness of the surfacing welded metal surface can reach HB≥170.

Since ZGMn13 belongs to high-carbon steel, its weldability is relatively poor: on the one hand, carbides are prone to precipitate in the weld heat-affected zone, causing material embrittlement; on the other hand, the tendency for hot cracks in the weld is relatively severe, especially in the area close to the weld, where liquefaction cracks are prone to occur. Therefore, before welding, a reasonable welding process must be formulated to ensure the quality of the surfacing welded metal layer and reduce the occurrence of welding defects.