The cause of cold bending cracking of SPA-H steel plate

SPA-H steel plate is a low carbon low alloy structural steel which is widely used in container plate production. Cold bending cracking is the most common defect of SPA-H container plate in the manufacturing process. The poor cold bending performance will directly affect the product quality and economic benefits.

A large number of spherical alumina inclusions are distributed on the surface of SPA-H steel plate, which are the main cause of cold bending cracking. These inclusions separate from the metal interface and form micro-holes around the SPA-H steel plate. With the deformation process, the holes grow and connect, and finally form large cracks or separate between the metal and the metal to form layers, leading to cold bending performance deterioration until cracking.