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

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

scholarly journals Corrosion Behavior of NiTi Alloys Fabricate by Selective Laser Melting Subjected to Femtosecond Laser Shock Peening

Coatings ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 1078
Author(s):  
Long Ma ◽  
Wanqing Li ◽  
Yongzhi Yang ◽  
Yuanxue Ma ◽  
Kai Luo ◽  
...  
Keyword(s):  
Corrosion Resistance ◽  
Femtosecond Laser ◽  
Selective Laser Melting ◽  
Niti Alloy ◽  
Laser Shock Peening ◽  
Laser Shock ◽  
Laser Melting ◽  
Corrosion Failure ◽  
Niti Alloys ◽  
Shock Peening

NiTi alloys are commonly used in many fields such as aerospace, mechanical engineering due to their excellent mechanical properties and shape memory effect. In recent years, the emergence of selective laser melting (SLM) technology provides a new method for the preparation of NiTi parts. But the surface corrosion failure of SLM-NiTi is the most common problem. This paper mainly focuses on the research of femtosecond laser shock peening of the surface of SLM-NiTi alloy to improve the corrosion resistance. Selecting different scanning space (1 μm, 3 μm, 5 μm, 10 μm), and analyze the surface morphology of the material through the OM, SEM, EDS and white light interferometer, and investigate the surface nanohardness and corrosion resistance through nanoindentation and electrochemical testing. The research results show that part of the TiO2 is formed under different scanning spaces, and part of NiO is formed when the scanning space is 1μm. At the same time, it is found that the sample under the condition of 10 μm has the most excellent corrosion resistance and nanohardness. The nanohardness reaches 1303 ± 40 HV and the corrosion current density reaches 1.45 ± 0.1 × 10−9 A·cm−2. Proper femtosecond laser treatment can effectively improve the surface strength and corrosion resistance of the NiTi alloys.

Corrosion behavior of NiTi alloy subjected to femtosecond laser shock peening without protective coating in air environment

2020 ◽  
Vol 501 ◽  
pp. 144338 ◽  
Author(s):  
Hao Wang ◽  
Jens Jürgensen ◽  
Peer Decker ◽  
Zhiyong Hu ◽  
Kai Yan ◽  
...  
Keyword(s):  
Femtosecond Laser ◽  
Corrosion Behavior ◽  
Protective Coating ◽  
Niti Alloy ◽  
Laser Shock Peening ◽  
Laser Shock ◽  
Shock Peening

Fatigue Life Recovery via Laser Shock Peening in Mechanically Damaged Aluminium Sheet; Experiments and Prediction Models

2014 ◽  
Vol 891-892 ◽  
pp. 980-985 ◽  
Author(s):  
Niall Smyth ◽  
Philip E. Irving
Keyword(s):  
Residual Stress ◽  
Fatigue Life ◽  
Prediction Models ◽  
Load Cycle ◽  
Laser Shock Peening ◽  
Stress Fields ◽  
Hole Drilling ◽  
Laser Shock ◽  
Aluminium Sheet ◽  
Shock Peening

This paper reports the effectiveness of residual stress fields induced by laser shock peening (LSP) to recover pristine fatigue life. Scratches 50 and 150 μm deep with 5 μm root radii were introduced into samples of 2024-T351 aluminium sheet 2 mm thick using a diamond tipped tool. LSP was applied along the scratch in a band 5 mm wide. Residual stress fields induced were measured using incremental hole drilling. Compressive residual stress at the surface was-78 MPa increasing to-204 MPa at a depth of 220 μm. Fatigue tests were performed on peened, unpeened, pristine and scribed samples. Scratches reduced fatigue lives by factors up to 22 and LSP restored 74% of pristine life. Unpeened samples fractured at the scratches however peened samples did not fracture at the scratches but instead on the untreated rear face of the samples. Crack initiation still occurred at the root of the scribes on or close to the first load cycle in both peened and unpeened samples. In peened samples the crack at the root of the scribe did not progress to failure, suggesting that residual stress did not affect initiation behaviour but instead FCGR. A residual stress model is presented to predict crack behaviour in peened samples.

Research on Mechanical Response of Copper Treated by Micro Laser Shock Peening Using Nanoindentation Technique

2011 ◽  
Vol 38 (6) ◽  
pp. 0603026 ◽  
Author(s):  
樊玉杰 Fan Yujie ◽  
周建忠 Zhou Jianzhong ◽  
黄舒 Huang Shu ◽  
范金荣 Fan Jinrong ◽  
王呈栋 Wang Chengdong ◽  
...  
Keyword(s):  
Mechanical Response ◽  
Laser Shock Peening ◽  
Laser Shock ◽  
Nanoindentation Technique ◽  
Shock Peening
Sign in / Sign up

Export Citation Format

Share Document