ANALYSIS OF SURFACE ROUGHNESS AT OVERLAPPING LASER SHOCK PEENING

The overlapping effects on surface roughness are studied when samples are treated by laser shock peening (LSP). Surface roughness of overlapped circular laser spot is calculated by ISO 25178 height parameters. The usually used overlapping styles namely isosceles-right-triangle-style (AAP) and equilateral-triangle-style (AAA) are carefully investigated when the overlapping degree in x-axis ([Formula: see text]) is below 50%. Surface roughness of isosceles-right-triangle-style attains its minimum value at [Formula: see text] of 29.3%, and attains its maximum value at [Formula: see text] of 43.6%. Surface roughness of equilateral-triangle-style attains its minimum value at [Formula: see text] of 42.3%, and attains its maximum value at [Formula: see text] of 32%. Experimental results are well consistent with theoretical analysis.

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Effect of Laser Shock Peening on the Structure and Prosperity of K403 Alloy

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.670-671.52 ◽

2014 ◽

Vol 670-671 ◽

pp. 52-55

Author(s):

Yan Chai ◽

Wei Feng He ◽

Guang Yu He ◽

Yu Qin Li

Keyword(s):

Surface Roughness ◽

Grain Boundary ◽

Compressive Stress ◽

Residual Compressive Stress ◽

Laser Shock Peening ◽

Test Results ◽

Laser Shock ◽

Surface Microhardness ◽

Shock Region ◽

Shock Peening

To solve the crack and fracture problem in blade made of K403 alloy, the samples of K403 are laser shock processed and then the microstructure, microhardness, residual compressive stress and surface roughness of the samples are tested. The test results show that some grains are observed refined in the grain boundary of shock region, the microhardness improves in a depth of 0.8mm from the surface and the surface microhardness improves 16%, a residual compressive stress which is more than 450MPa is developed in a depth of 1mm from the surface, and obvious changes of the surface roughness are not tested.

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Effect of Laser Shock Peening on the Wear–Corrosion Synergistic Behavior of an AZ31B Magnesium Alloy

Journal of Tribology ◽

10.1115/1.4045500 ◽

2019 ◽

Vol 142 (4) ◽

Cited By ~ 1

Author(s):

Arpith Siddaiah ◽

Bo Mao ◽

Yiliang Liao ◽

Pradeep L. Menezes

Keyword(s):

Surface Roughness ◽

Galvanic Corrosion ◽

Open Circuit ◽

Laser Shock Peening ◽

Laser Shock ◽

Accelerated Corrosion ◽

Functional Behavior ◽

Zero Resistance ◽

Shock Peening ◽

Synergistic Behavior

Abstract Laser shock peening (LSP) is one of the widely used surface processing techniques for tailoring functional behavior of surfaces. LSP has been used to enhance friction, wear, and mechanical properties. However, understanding of LSP-treated surfaces involving tribological contacts in electrochemically active environments is limited because the mechanism of wear–corrosion interactions (tribocorrosion) for such surfaces is still unclear. In the present study, the effect of LSP on the wear–corrosion behavior of an AZ31B Mg alloy is investigated. A zero-resistance ammeter (ZRA) method is utilized to examine the evolution of open circuit potential (OCP) during wear–corrosion analysis. The study finds that the LSP processing can decrease the corrosion potential difference between worn and unworn regions of the surface, thereby mitigating the effect of wear-accelerated corrosion during sliding. The effect of wear-accelerated corrosion is evident from the change in average surface roughness (Sa) of the unworn areas. It is found that understanding the change in surface roughness due to wear–corrosion interactions is necessary to investigate the onset and propagation of galvanic corrosion. Based on these results, the study details the mechanism of wear–corrosion interactions during sliding.

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Finite Element Analysis of Surface Roughness Generated by Multiple Laser Shock Peening

Rare Metal Materials and Engineering ◽

10.1016/s1875-5372(18)30067-5 ◽

2018 ◽

Vol 47 (1) ◽

pp. 33-38 ◽

Cited By ~ 5

Author(s):

Zhu Ran ◽

Zhang Yongkang ◽

Sun Guifang ◽

Shen Xuting ◽

Li Pu

Keyword(s):

Finite Element Analysis ◽

Surface Roughness ◽

Finite Element ◽

Laser Shock Peening ◽

Laser Shock ◽

Element Analysis ◽

Shock Peening

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Influence of Nd: YAG Laser Parameters on Tensile Behaviour, Microhardness and Surface Roughness of Ni-Cr Alloy for Dental Prostheses

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.766-767.539 ◽

2015 ◽

Vol 766-767 ◽

pp. 539-545

Author(s):

K. Gurusami ◽

Karibeeran Shanmuga Sundaram ◽

R. Vijay

Keyword(s):

Surface Roughness ◽

Test Method ◽

Laser Shock Peening ◽

Tensile Behaviour ◽

Laser Shock ◽

Yag Laser ◽

Mean Values ◽

Dental Prostheses ◽

The Mean ◽

Shock Peening

The paper presents the results of tensile behaviour, microhardness, surface roughness and microstructure of Ni-Cr alloy surface treated using high power Q-switched Nd: YAG laser has been studied. The major clinical disadvantage of the Ni – Cr is their lack of adequate ductility and yield strength. These properties combined made finishing, polishing and burnishing of conventional base metal alloys rather difficult. The dumbbell shaped tensile and cylindrical specimens of Ni-Cr were cast with a phosphate bonded investment material, using an induction melting centrifugal casting machine. The microhardness values of the surface melted layers increased as compared with Ni-Cr as - cast condition. The results of experiment showed that the surface treatment process has improved the % elongation, and surface roughness and microhardness as compared with as-cast. The improvement of the mechanical properties may be attributed due to grain refinement imparted by laser shock peening. The microstructure and changes in crystal orientation presented in the surface layer of the laser treated material were analyzed by optical, SEM as well as XRD. The chemical composition of laser treated surface was determined by EDAX attached along with SEM. Vickers microhardness was measured as per ASTM E384 11el standard test method. The data were compared using ANOVA and post hoc –Tukey test. In our present study, the laser shock peening process shows, a substantial increase in surface roughness from Ra = 0.440 μm before LSP treatment to 1.781 μm and surface hardness of Ni-Cr was achieved by 53.5% the base material hardness (i.e. from284 HV to 436 HV) and the mean values of % elongation of Ni-Cr alloy was higher (double) than that of after laser shock peening. The mean values of UTS, YS, modulus of elasticity of Ni-Cr were significantly lower after LSP. The experimental results showed that the mean values of percentage elongation of Ni-Cr increased by 200 % after LSP. It is evident from the above experimentation, increase of ductility of Ni-Cr alloy facilities workability which could produce a reliable removable partial denture (RPD) metal framework for dental prostheses.

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