![]() ![]() These cracks propagate between weld deposit grains or the interface of the welding. Hot cracking is found mostly at the center of the weld as, during solidification, this is the area that solidifies at the last. The main reason for hot cracks is the lack of ductility at elevated temperatures. Hot cracking appears at the solidification stage of the welding. Trans-crystalline crack: Cracks propagating through complete microstructure areas.I nter-crystalline crack: Cracks propagating along the grains.Microcracks: Visible under a metallographic microscopeįurther classification can be based on how the cracks propagate, as:.Macro cracks: Visible with the naked eye or with a magnifying glass.Load caused cracking: Stress corrosion cracking, Hydrogen cracking Types of Welding Cracks Based on SizeĬracks based on their size are classified into:.Technologically caused Cracking: Crack due to wrong heat treatment.Metallurgical caused cracking: Hot crack, Shrinkage Crack.In welding cracks, there is little plastic deformation as most of the cracks either occur due to high hardness or Stress. In welding, residual stresses are caused by weld solidification and thermal expansion properties of the metal. These stresses can be residual stresses caused by the welding or stresses got applied due to service or another external loading. Initial Cracking usually starts at stress concentrations due to other defects or sharp notches (notches work as stress concentration) in the nearby area. They occur once the localized stresses exceed the ultimate tensile strength of the base metal. Welding cracks can appear in weld deposits, heat-affected zone (HAZ), and base material. Welding Cracks are fracture-type linear imperfections having a sharp tip with a higher length and very small width. Cracks are in most cases starting points of a fracture. A welding crack is a material separation that does not encompass the entire cross-section of a welding joint, component, or material, not yet causing it to fall apart. ![]()
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