Fabrication of a gradient nano-micro-structured surface layer on bulk copper by means of a surface mechanical grinding treatment

Microstructural evolutions and stability of gradient nano-grained copper under tensile tests and subsequent storage

“…Then both the gauge section and the arc transitions of the samples were subjected to SMGT. The basic principle and detailed procedure of the SMGT process have been described elsewhere [13]. In this study, the applied SMGT processing parameters are as follows: rotation speed υ1 = 600 rpm, sliding velocity of the tool tip υ2 = 3 mm s -1 , penetration depth of the tool tip into the sample ap = 40 μm, and the Cu rod was cooled to a cryogenic temperature of ~173 K with liquid nitrogen during the SMGT process.…”

“…More recently, by means of a surface mechanical grinding treatment (SMGT) [13], a spatial gradient nano-grained (GNG) layer was produced on the surface of a bulk coarse-grained (CG) Cu rod. The surface NG layer exhibits a 10 times higher yield strength and a uniform tensile plasticity comparable to that of the CG substrate.…”

Gradient nanostructured surface of a Cu plate processed by incremental frictional sliding

“…Various techniques have been developed to produce such surfaces [2][3][4][5][6], but there is room for technique development in terms of flexibility in sample geometry, thickness of the hardened layer, efficiency of the processing, etc. This development must be followed up and underpinned by quantitative characterization and analysis of microstructures and properties, as is also part of the present study.…”

Lead-induced stress corrosion cracking behavior of mechanically surface-treated alloy 690

“…Surface mechanical attrition treatment (SMAT), [18] in which the repeated multidirectional impacts at high strain rates onto the specimen surface result in severe plastic deformation and grain refinement progressively down to the nanometer regime in the entire specimen surface, is one of the important ways to significantly improve mechanical properties of metallic materials.…”

“…The details of the SMAT process were described in an earlier paper. [18] The C-ring test specimens were prepared under the ASTM G 38-37 code [19] and the applied stress was adopted as 414 MPa and the corrosion time is up to 2160 h. The C-ring SCC tests were performed in simulated alkaline SG crevice chemistries at 300°C. The corrosive environment was alkaline SG chemistries with or without 2.2 mM (500 ppm) PbO with pH at 12.7.…”