Effect of Surface Mechanical Treatments on the Microstructure-Property-Performance of Engineering Alloys

Abstract

Fatigue is a dominant failure mechanism of several engineering components. One technique for increasing the fatigue life is by inducing surface residual stress to inhibit crack initiation. In this review, a microstructural study under various bulk (such as severe plastic deformation) and surface mechanical treatments is detailed. The effect of individual microstructural feature, residual stress, and strain hardening on mechanical properties and fatigue crack mechanisms are discussed in detail with a focus on nickel-based superalloys. Attention is given to the gradient microstructure and interface boundary behavior for the mechanical performance. It is recommended that hybrid processes, such as shot peening (SP) followed by deep cold rolling (DCR), could enhance fatigue life. The technical and scientific understanding of microstructural features delineated here could be useful for developing materials for fatigue performance.

Mechanical and Tribological Characteristics of Cladded AISI 1045 Carbon Steel

“…Moreover, the induced residual stress could be responsible for the lower surface hardness in comparison with the subsurface [32]. The mechanism of the increase in surface hardness with respect to depth is a result of grain size refinement and work hardening induced by plastic strain [33]. Specifically, in AM materials, the elimination of surface defects such as porosities, cracks, etc., may also be responsible for the increase in surface hardness with respect to depth [34].…”

“…At the same time, it is clear from Figure 8d that the intensity peaks of the UNSM-treated single and double layers increased with respect to the polished single and double layers and also shifted towards a lower diffraction angle. It is widely known that mechanical surface modification processes can lead to peak shifts to a lower diffraction angle by increasing uniform compressive strain, while it is also important to mention here that higher diffraction angles can be caused through grain reorientation and nonuniform compressive strain [33,35]. Moreover, 2θ position and full width at half maximum (FWHM) value information obtained from XRD patterns of the polished and UNSM-treated single Figure 8a shows the comparison of the XRD patterns of the polished and UNSM-treated single and double layers.…”

Influence of residual stress distribution and microstructural characteristics on fatigue failure mechanism in Ni‐based Superalloy

“…1 RCS play a critical role in controlling or impeding the fatigue crack initiation and propagation of nickel-based superalloys. 2 In contrast, tensile stresses generated during machining and polishing provide an adverse effect on fatigue life. Surface mechanical treatments such as shot peening (SP) 3 and laser shock peening (LSP) 4,5 are two commercially used processes to induce RCS.…”

A novel approach toward microstructure evaluation of sintered ceramic materials through image processing techniques

“…Grain size is a significant parameter, given its influence on mechanical properties, for example, strain, ductility, protection from stress, etc. [12][13][14] Colás and Maropoulos et al 15,16 examined the connection between grain size and thermal treatments using stainless steel and low alloy steel. Horovistiz et al 17 developed a method to obtain measurable information about grain size and shape from fractured surfaces of ceramic materials.…”

“…Dengiz et al 11 used neural network and fuzzy logic algorithms to detect the grain boundary of steel alloys. Grain size is a significant parameter, given its influence on mechanical properties, for example, strain, ductility, protection from stress, etc 12–14 . Colás and Maropoulos et al 15,16 examined the connection between grain size and thermal treatments using stainless steel and low alloy steel.…”