The Influence of Shot Peening on the Fatigue Behavior of Gray Cast Iron and Ductile Iron

Author:  M. Wollmann, S. Koda, L Wagner
Source:  Conf Proc 2014: ICSP-12 Goslar, Germany (pgs.61-67)
Doc ID:  2014051
Year of Publication:  2014
Abstract:  
The fatigue response of cast irons have been investigated in rotating beam loading (R = -1) on smooth (kt = 1) and notched (kt = 2.3) specimens with lamellar as well as nodular graphite constituents. The lamellar cast iron denoted as GJL 200 had a ferritic perlitic matrix while the nodular graphite features of GJS 350 were embedded in a ferritic matrix. As expected, the tensile strengths were quite different amounting to 200 and 370 MPa for the lamellar and nodular materials, respectively. Shot peening was applied on both materials on smooth and notched specimens. The lamellar cast iron showed an improvement in fatigue strength due to shot peening compared to the mechanically polished reference. The endurance limit after shot peening amounted to about 75 MPa. For notched specimens, there was a slight improvement in endurance limit from about 50 MPa to about 80 MPa after shot peening. Comparable observations were made with ductile cast iron