The New Technologies Developed from Laser Shock Processing

Abstract

Laser shock processing (LSP) is an advanced material surface hardening technology that can significantly improve mechanical properties and extend service life by using the stress effect generated by laser-induced plasma shock waves, which has been increasingly applied in the processing fields of metallic materials and alloys. With the rapidly development of modern industry, many new technologies developed from LSP have emerged, which broadens the application of LSP and enriches its technical theory. In this work, the technical theory of LSP was summarized, which consists of the fundamental principle of LSP and the laser-induced plasma shock wave. The new technologies, developed from LSP, are introduced in detail from the aspect of laser shock forming (LSF), warm laser shock processing (WLSP), laser shock marking (LSM) and laser shock imprinting (LSI). The common feature of LSP and these new technologies developed from LSP is the utilization of the laser-generated stress effects rather than the laser thermal effect. LSF is utilized to modify the curvature of metal sheet through the laser-induced high dynamic loading. The material strength and the stability of residual stress and micro-structures by WLSP treatment are higher than that by LSP treatment, due to WLSP combining the advantages of LSP, dynamic strain aging (DSA) and dynamic precipitation (DP). LSM is an effective method to obtain the visualized marks on the surface of metallic materials or alloys, and its critical aspect is the preparation of the absorbing layer with a designed shape and suitable thickness. At the high strain rates induced by LSP, LSI has the ability to complete the direct imprinting over the large-scale ultrasmooth complex 3D nanostructures arrays on the surface of crystalline metals. This work has important reference value and guiding significance for researchers to further understand the LSP theory and the new technologies developed from LSP.

Peening Techniques for Surface Modification: Processes, Properties, and Applications

“…LSP techniques have wide application in aerospace, nuclear, biomedical, marine, and automotive industries. In the aerospace industry, LSP is used in passenger and military flights to enhance the fatigue performance of the compressor blade, landing gears, shafts, valves, discs, and complex forming of wing surfaces [ 159 , 160 ]. Hammersley et al [ 159 ] demonstrated the effect of LSP on fatigue strength of turbine fan blades, which are made of Ti6Al4V.…”

Recent Research and Development Status of Relaxed Optics and Laser Technology: A Review

“…Problems of the observation the laser-induced optical breakdown and shock processes in matter as Nonlinear Optical (NLO) and Relaxed Optical (RO) processes are connected with acoustic (thermal) and electromagnetic (plasma and Nonlinear optical) nature [2] [7] [8] [9] [28]- [33]. These processes may be connected with diffractive stratification of laser beam, self-focusing, self-trapping, generation of supercontinuum radiation (ordered: Cherenkov radiation, and disorder: plasma radiation) [7] [8] [34] [35] [36].…”

“…These processes may be connected with diffractive stratification of laser beam, self-focusing, self-trapping, generation of supercontinuum radiation (ordered: Cherenkov radiation, and disorder: plasma radiation) [7] [8] [34] [35] [36]. We present this problem from one point of view for all media from gases to solid [2] [3] [7] [8] [28]- [33]. Unfortunately, the first attempt of observation this problem in main detail in whole are represented in [7] [8] only.…”

“…The second order irradiation has Cherenkov nature [7] [8] [34]. The experimental data were received for picosecond and femtosecond regimes of irradiation [7] [8] [28]- [33]. This differentiation is connected with various nature of relaxation of first-order optical excitation.…”

“…Evacuation of power excess undergone by the primary filaments finally allows transfer of power to the central zone of the beam, which serves as an energy reservoir for exciting new sequences of small spots (z = 50 m) (Figure 21). Numerical data were represented for duration of pulse 85 fs and power few terawatt [33]. From these results specific geometrical zones in the beam pattern were selected [32].…”