Application Of Ceramic Shot For Peening Of Automotive Suspension Coil Springs

Author:  Abadie, Beaudonnet, Dixon, Fader, Fabre, Barrallie
Source:  Conf Proc: ICSP-10 Tokyo, Japan 2008
Doc ID:  2008082
Year of Publication:  2008
Abstract:  
ABSTRACT The use of ceramic shot for the improvement of high strength steel endurance is confirmed to enhance coil spring fatigue life by improving the surface condition and providing high levels of residual stress at the surface. Since the last conference in 2005 [1], a major technology development effort led by MSSC has resulted in the implementation of 2nd stage ceramic peening process in an industrial application for highly loaded suspension coil springs. Industrial benefits and a significant improvement in coil spring fatigue life have been observed. This paper reports on upgraded knowledge on ceramic peening and industrial results, including case studies on actual parts. The analysis of actual coils provides a good understanding of the benefits of ceramic peening on the material - lower surface damage and less disturbed roughness with high compressive residual stress close to the surface. KEYWORDS High strength steel, automotive suspension coil springs, double shot peening, ceramic shot, steel shot, fatigue life.