Enhanced mechanical properties in Cu–Zn alloys with a gradient structure by surface mechanical attrition treatment at cryogenic temperature

Surface nanocrystallization and gradient structure developed in the bulk TC4 alloy processed by shot peening

“…Cai et al [19] fabricated a GNS surface layer of Cu-Zn alloys via surface mechanical attrition treatment (SMAT) and illustrated the superior strength-ductility synergy. Yang et al [20] and Huang et al [21] showed that the GNS surface layer of pure Cu and AISI 316L stainless steel processed by SMAT promoted fatigue resistance.…”

Mechanical Behavior of Ultrafine Gradient Grain Structures Produced via Ambient and Cryogenic Surface Mechanical Attrition Treatment in Iron

“…While still exhibiting good ductility, the grain size gradient in Cu-Zn [33] does not improve upon the strength-ductility tradeoff in homogenous grain size materials as significantly as the copper [5] and steel [25] gradients. The grain refinement in the Cu-Zn study is not quantified, but most of the grain sizes in the gradient appear to be much larger than 1 μm; additionally, the hardness measurements indicate that the entire thickness of the tensile samples (600 μm) has been plastically deformed, preventing the unusual elongation and hardening behavior accessed by the studies including the undeformed core [5,25].…”

“…The standard strength-ductility tradeoff associated with grain refinement is shown in Figure 4-a typical boundary region is shown with the dashed curve drawn through data points for homogeneous grain structures of the same material as the gradient structures: pure iron [34] (gray circles), pure copper [31,[35][36][37][38][39][40] (gray diamonds), steel [25] (gray triangles), and Cu-Zn alloys [33] (gray squares). These points are data from bulk samples of various homogeneous grain sizes and processing methods for comparison with the gradient grain structures of the sample material.…”

“…Tensile data existing for gradient grain structures are depicted for the iron SMAT in this work (magenta circles), Cu-Zn alloys [33] (red squares), copper [5] (orange diamond); steel [25] (black triangle). Literature values for bulk structures in the same materials are shown in gray (iron: gray circles [34], steel: grey triangles [25] and references therein, Cu-Zn alloys: grey squares [33] and references therein, copper: gray diamonds [31,[35][36][37][38][39][40]).…”

“…Literature values for bulk structures in the same materials are shown in gray (iron: gray circles [34], steel: grey triangles [25] and references therein, Cu-Zn alloys: grey squares [33] and references therein, copper: gray diamonds [31,[35][36][37][38][39][40]). The strength ductility tradeoff is illustrated by the dotted line.…”