Effect of laser shock peening and heat‑treated on surface hardness of Ti–6Al–4V

Abstract The applications of magnesium (Mg) and their alloys are often restricted by their poor formability at room temperature. Several strategies have been developed in recent years to enhance the formability of Mg alloys, such as grain refinement and texture weakening, either by alloying or processing. Laser shock peening (LSP) is an advanced laser-based surface processing method which has been utilized improve the surface hardness, fatigue performance, and corrosion resistance of Mg alloys. Recent studies show that LSP can bring significant texture weakening and grain refinement effect in Mg alloy, indicating its potential capability of enhancing the formability of Mg alloys. This research is to explore the applicability of LSP to improve the room temperature-stretch formability of Mg alloys. LSP experiments are carried out on an AZ31B Mg alloys. The microstructure before and after LSP are characterized by optical microscopy (OM) and electron backscattered diffraction (EBSD) microscopy. Erichsen tests are carried out to evaluate the stretch formability of Mg alloys. The results show that LSP can bring texture weakening and grain refinement effect simultaneously, resulting in the improved room temperature-stretch formability of Mg alloys.

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Impact on Mechanical Properties and Microstructural Response of Nickel-Based Superalloy GH4169 Subjected to Warm Laser Shock Peening

Materials ◽

10.3390/ma13225172 ◽

2020 ◽

Vol 13 (22) ◽

pp. 5172

Author(s):

Ying Lu ◽

Yuling Yang ◽

Jibin Zhao ◽

Yuqi Yang ◽

Hongchao Qiao ◽

...

Keyword(s):

Surface Treatment ◽

Compressive Stress ◽

Surface Hardness ◽

Residual Compressive Stress ◽

Laser Shock Peening ◽

Effect Of Temperature ◽

Laser Shock ◽

Treatment Technology ◽

Shock Peening ◽

Gh4169 Alloy

Laser shock peening (LSP), as an innovative surface treatment technology, can effectively improve fatigue life, surface hardness, corrosion resistance, and residual compressive stress. Compared with laser shock peening, warm laser shock peening (WLSP) is a newer surface treatment technology used to improve materials’ surface performances, which takes advantage of thermal mechanical effects on stress strengthening and microstructure strengthening, resulting in a more stable distribution of residual compressive stress under the heating and cyclic loading process. In this paper, the microstructure of the GH4169 nickel superalloy processed by WLSP technology with different laser parameters was investigated. The proliferation and tangling of dislocations in GH4169 were observed, and the dislocation density increased after WLSP treatment. The influences of different treatments by LSP and WLSP on the microhardness distribution of the surface and along the cross-sectional depth were investigated. The microstructure evolution of the GH4169 alloy being shocked with WLSP was studied by TEM. The effect of temperature on the stability of the high-temperature microstructure and properties of the GH4169 alloy shocked by WLSP was investigated.

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Effect of Post Laser Shock Peening on Microstructure and Mechanical Properties of Inconel 718 by Selective Laser Melting

Volume 2: Processes; Materials ◽

10.1115/msec2019-2893 ◽

2019 ◽

Author(s):

Kuldeep Singh Sidhu ◽

Yachao Wang ◽

Jing Shi ◽

Vijay K. Vasudevan ◽

Seetha Ramaiah Mannava

Keyword(s):

Mechanical Properties ◽

Residual Stress ◽

Inconel 718 ◽

Compressive Residual Stress ◽

High Energy ◽

Laser Shock Peening ◽

Laser Shock ◽

Laser Melting ◽

Heat Treated ◽

Shock Peening

Abstract This study investigates the effects of laser shock peening (LSP) on residual stress, near surface modification, and hardness of Inconel 718 (IN718) specimens manufactured by selective laser melting (SLM) technique. Optical microscope and electron backscattered diffraction (EBSD) is used to characterize the microstructures of both heat-treated and as-built specimens. A nanoindentation test is performed to determine the properties such as the hardness of as-built and heat-treated specimens. Afterward, the hardness along the distance from the LSP treated surface is also defined. To investigate the effect of LSP energy on the mechanical properties of specimens, two levels of LSP energy, e.g., low energy LSP (6.37 GW/cm2) and high energy LSP (8.60 GW/cm2), are carried out on selected samples. With the increase in laser energy density, it is found that both compressive residual stress and hardness increase after LSP treatment. The as-built specimens after high energy LSP treatment show the compressive residual stress of −875 MPa, and the surface hardness increases from 468 HV to 853 HV.

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Application of nanoindentation technique to test surface hardness and residual stress of NiTi alloy after femtosecond laser shock peening

High-Power Laser Materials Processing: Applications, Diagnostics, and Systems X ◽

10.1117/12.2593092 ◽

2021 ◽

Author(s):

Hao Wang ◽

Evgeny L. Gurevich ◽

Andreas Ostendorf

Keyword(s):

Residual Stress ◽

Femtosecond Laser ◽

Niti Alloy ◽

Surface Hardness ◽

Laser Shock Peening ◽

Test Surface ◽

Laser Shock ◽

Nanoindentation Technique ◽

Shock Peening

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Impact-Sliding Tribology Behavior of TC17 Alloy Treated by Laser Shock Peening

10.20944/preprints201806.0125.v1 ◽

2018 ◽

Author(s):

Meigui Yin ◽

Wenjian Wang ◽

Weifeng He ◽

Zhenbing Cai

Keyword(s):

Sliding Wear ◽

Wear Behavior ◽

Surface Hardness ◽

Wear Test ◽

Laser Shock Peening ◽

Wear Testing ◽

Laser Shock ◽

Shock Peening ◽

Multiple Impact ◽

The Impact

Outer particles collision with certain dynamic object is not a pure impact wear behavior; it is typically accompanied by sliding wear phenomena. This study aimed investigating the impact-sliding wear performance of three different TC17 titanium alloys. One was untreated, and the other two were subjected to laser shock peening (LSP) by 5 and 7 J pulse energy, respectively. Wear test was performed on a novel impact-sliding wear testing rig, which can realize multiple impact-sliding motions by changing motion parameters in x and z directions. Present results showed that wear resistance of both treated samples improved compared with the untreated alloy. Given the increase in wear cycles, increment in wear rate of the untreated sample was constantly higher than those of treated samples. All results can be attributed to the increase in surface hardness of the material and residual compressive stress, which was also introduced after LSP.

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Impact-Sliding Tribology Behavior of TC17 Alloy Treated by Laser Shock Peening

Materials ◽

10.3390/ma11071229 ◽

2018 ◽

Vol 11 (7) ◽

pp. 1229 ◽

Cited By ~ 3

Author(s):

Meigui Yin ◽

Wenjian Wang ◽

Weifeng He ◽

Zhenbing Cai

Keyword(s):

Sliding Wear ◽

Wear Behavior ◽

Surface Hardness ◽

Wear Test ◽

Laser Shock Peening ◽

Wear Testing ◽

Particle Collision ◽

Laser Shock ◽

Shock Peening ◽

The Impact

Outer particle collision with certain dynamic objects is not a pure impact wear behavior; it is typically accompanied by sliding wear phenomena. This study is aimed at investigating the impact-sliding wear performance of three different TC17 titanium alloys. One was untreated, and the other two were subjected to laser shock peening (LSP) by 5 and 7 J pulse energy, respectively. The wear test was performed on a novel impact-sliding wear testing rig, which can realize multiple impact-sliding motions by changing motion parameters in the x and z directions. Present results showed that wear resistance of both treated samples improved compared with the untreated alloy. Given the increase in wear cycles, increment in wear rate of the untreated sample was constantly higher than those of the treated samples. All results can be attributed to the increase in surface hardness of the material and residual compressive stress, which was also introduced after LSP.

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