Welding characteristics of high carbon steel

High carbon steel has poor weldability due to its high carbon content. Its welding has the following characteristics:
(1) The thermal conductivity is poor, and a significant temperature difference is generated between the welded portion and the unheated portion. When the molten pool is rapidly cooled, the internal stress caused in the weld is likely to form a crack.
(2) It is more sensitive to quenching, and martensite structure is easily formed in the near seam area. Due to the action of the tissue stress, cold cracks are generated in the near seam region.
(3) Due to the influence of high temperature welding, the grain grows fast, the carbide easily accumulates and grows on the grain boundary, the weld is weak, and the strength of the welded joint is lowered.
(4) High carbon steel is more prone to hot cracking than medium carbon steel when welded.