A Simplified Residual Stress Model for Predicting Fatigue Crack Growth Behavior 'at Coldworked Fastener Holes
نویسنده
چکیده
This paper presents an investigation of the fatigue crack growth (FCG) behavior at fastener holes in a high strength steel. 30CrMnSiNi2A, before and after a cold-expansion process. The fatigue life of coldworked specimens was signitkantly increased compared to non-wldworked ones and increased the !O\ver applied stress level. From a study' nf the residual stress distribution near the edgc of the hole. it \vas found that the cxperlmental residual comprcsslve stresses in absolutc values werc much less than the calculated \'alues derived by prcvious analytical methods. Thus. a simplified residual stress model '"or descrihing the reG hehavior at cold\\'orkcd fastener holes is proposed, from whIch. thc .::.,.1(1£ and fatigue livcs l)f spccimens aftcr ~()ld-cxpansion can be predicted 'latlsfactonly l'or cnglf1ccring ap'piicatlons.
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