Recent Developments and Novel Applications of Laser Shock Peening: A Review

Carbide-facilitated nanocrystallization of martensitic laths and carbide deformation in AISI 420 stainless steel during laser shock peening

The plastic deformation behavior of Ti6Al4V titanium alloy subjected to 300 °C-warm laser shock peening (WLSP) was inferred from its microstructure evolution and mechanical properties. Through dynamic strain aging (DSA), WLSP achieved higher dense dislocations than room temperature laser shock peening (LSP). In addition, significant 10 1 — 2 deformation twinning activity was observed after WLSP. Twinning activity at such an ultrahigh strain rate and high temperature is a first-time observation in titanium alloy, and was attributed to an enhanced dislocation dissociation mechanism during WLSP. Moreover, an amorphization layer was generated on the top surface of the WLSP-processed sample, but not on the LSP-processed sample. This amorphization was effected by the increased free energy provided by the multiplying dislocations and deformation twins, combined with the reduced energy barrier of the crystal-to-amorphous transformation at high temperature. Relative to LSP, WLSP increased the width and depth of the compressive residual stress in the titanium alloy by 36.2% and 21.8% respectively, and improved the surface microhardness by 5%. The latter enhancement was conferred by the increased density of dislocations and deformation twins. Overall, WLSP improved the mechanical properties of the titanium alloy.

Plastic deformation behavior of titanium alloy by warm laser shock peening: Microstructure evolution and mechanical properties

Achieving high strength and ductility in selective laser melting Ti-6Al-4V alloy by laser shock peening

Improving high cycle fatigue performance of gas tungsten arc welded Ti6Al4V titanium alloy by warm laser shock peening

Effect of dynamic recrystallization on texture orientation and grain refinement of Ti6Al4V titanium alloy subjected to laser shock peening

Investigations on femtosecond laser-induced surface modification and periodic micropatterning with anti-friction properties on Ti6Al4V titanium alloy

It is well understood that the components with holes used in aviation and aerospace industries are generally vulnerable to alternate cycles of working stress during their service, which are weakest parts and highly prone to failure and fracture due to the stress concentration at the edge of hole. To improve the resistance towards fatigue failure of the hole, laser shock peening (LSP) technology is successfully applied to the hole on powder metallurgy (P/M) Ni-based superalloy labyrinth disc in present work and significant 18% increase in high cycle fatigue limit is achieved (from 224 ± 4 MPa to 265 ± 6 MPa). The notable effects of LSP on the residual stress, microhardness and microstructure of the hole with and without LSP is investigated based on experimental and simulation method. It is found the large improvement of fatigue limit is attributed to the comprehensive action of high amplitude compressive residual stress and microhardness, grain refinement and the removement of inclusions caused by LSP. The finding here in promoting the fatigue resistance of hole by LSP are general and flexible, thereby exhibiting a potential application to a wide spectrum of engineering components with hole structures.

Xinlei Pan

Papers

Effect of dynamic recrystallization on texture orientation and grain refinement of Ti6Al4V titanium alloy subjected to laser shock peening

Plastic deformation behavior of titanium alloy by warm laser shock peening: Microstructure evolution and mechanical properties

Improving high cycle fatigue performance of gas tungsten arc welded Ti6Al4V titanium alloy by warm laser shock peening

Investigations on femtosecond laser-induced surface modification and periodic micropatterning with anti-friction properties on Ti6Al4V titanium alloy

Fatigue performance improvement of laser shock peened hole on powder metallurgy Ni-based superalloy labyrinth disc