A detailed failure analysis of a cold rolling roll after service is proposed; the numerical simulation was performed following a semi-analytical approach. A finite element analysis of the roll was performed by using the pressure distribution obtained with the Bland and Ford solution of the Von Karman's equation. According to previous studies available in literature on rolling fatigue, the Crossland multiaxial fatigue criterion was applied to perform a durability analysis. Fatigue limit under fully reversed bending of the cemented carbide material of the roll was obtained with Murakami Endo equation, applied close to a pore. Material characterization was performed with SEM and EDXS in proximity of the fracture surface. The failure analysis showed that the rolls failed primarily because of rolling fatigue, starting from an internal pore that acted as local stress raiser. The pore was positioned at 600 μm from the surface, where the Crossland criteria gives high criticality.
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