Aiming at the problem of bending cracks during the processing of 45Mn steel parts,the causes of bending cracks were analyzed and the production practice of improving the cold bending property of 45Mn steel through the slab hot spraying process was introduced.The results show that the presence of a fully decarburized layer and an intergranular oxide layer on the plate sur-face,along with the tensile stress on the outer surface during bending,lead to stress concentration at the interface of these lay-ers,resulting in microcracks that serve as the initiation point for cracking.This is the primary cause of bending cracks during the processing of 45Mn steel parts.Under the condition of identical chemical composition and matrix microstructure,the intergranu-lar oxidation on the surface of 45Mn steel is the main factor affecting its cold bending property.The application of a hot spraying anti-oxidation coating process on the slab before hot rolling can effectively inhibit the formation of intergranular oxidation on the plate surface,improving the cold bending property of 45Mn steel,enabling it to bend 180° without cracking,and there is no sig-nificant impact on its tensile strength,yield strength and elongation.
维普
万方数据