|About this Abstract
||2017 TMS Annual Meeting & Exhibition
||Multiscale Architectured Materials (MAM II): Tailoring Mechanical Incompatibility for Superior Properties
||Suppression of Surface Fatigue Cracking in Steels with a Gradient Nanostructured Surface Layer
||Z.B. Wang, K. Zhang, H.W. Huang, K. Lu
|On-Site Speaker (Planned)
By means of surface mechanical rolling treatment (SMRT), a gradient nanostructured (GNS) surface layer is generated on steel samples with different microstructures. In a GNS surface layer, the mean grain size is in nanometer scale at the treated surface and gradually increases with depth, accompanied with a decreasing hardness. In comparison with traditional surface treatments such as shot peening and deep rolling, the GNS layers are much thicker in the SMRT samples. In this talk, correlations between microstructure and fatigue properties are studied on different SMRT steel samples in terms of crack initiation and propagation, residual stress, and cyclic deformation response. The results indicated that under cyclic loading, surface crack initiation is effectively suppressed by the GNS surface layers and most cracks are initiated in the subsurface. Fatigue properties of the SMRT samples are significantly enhanced with a higher fatigue strength and/or a longer lifetime relative to the untreated specimens.