Application of UNSM (Ultrasonic Nanocrystal Surface Modification) Technology for Prolonging the Service life of AISI 1045 She

Author:  Pyoun, Cho, Suh, Park, Rogers, Kayumov, Murakami
Source:  Conf Proc 2011: ICSP-11 South Bend, IN USA (pgs. 171-175)
Doc ID:  2011028
Year of Publication:  2011
Abstract:  
Due to increasing productivity and fluctuation of roll torque, premature failure of shear pin of flange yoke assembly of stainless hot rolling mill occur and cause significant production loss. UNSM treatment was applied to the neck groove of the shear pin as an alternative to existing solutions to prevent premature failure and increase service life. Proper process variables of UNSM technology are determined which can give the strongest fatigue strength by the comparison of S-N curve of rotary bending test result. The surface roughness, hardness and compressive residual stress of three kinds of test specimens are analyzed together with SEM analysis of fracture surface. Real shear pins had been produced by the highest fatigue strength condition and installed to the hot mill stand for validation. They had been passed 270 days of operation.