FRACTURE ANALYSIS OF 40Cr STEEL ROLL

The reason of roll fracture has been analyzed by means of chemical composition analysis,macro fractograph,low magnification structure and microstructure examination. It′s showed that the roll is of bad quality. For example,chemical composition and general spotted segregation exceed the standard specification. Interior blowhole badly appears,which is the main reason resulting the roll fracture. Thus,corresponding measure and suggestion have been put forward.