Effects of Multiple Laser Peening impacts on Mechanical Properties and Microstructure Evolution of 40CrNiMo Steel

  • Huan Chen
  • Aixin FengEmail author
  • Jing Li
  • Tiandai Jia
  • Yong Liu


The effects of multiple laser peening impacts on mechanical properties and microstructure of 40CrNiMo steel were investigated. The surface residual stress and microhardness of the samples with different treatments were measured. The surface morphologies, tensile behavior and microstructure of the samples before and after laser peening were compared and analyzed. The experimental results showed that laser peening, especially multiple laser peening impacts has significant effects on the microhardness, residual stress and microstructure of 40CrNiMo steel. The surface roughness and the depth of the pit increased with increasing the impact times. After 3 laser peening impacts, the surface microhardness, compressive residual stress, the strength and ductility were significantly improved. Meanwhile, some microstructures, such as sub-grains, the precipitation of carbide and dislocations were also induced in the surface layer. Additionally, the microscopic strengthening mechanism of multiple laser peening impacts on the mechanical properties of 40CrNiMo steel was analyzed in detail.


40CrNiMo steel laser peening mechanical properties microstructure 



The authors acknowledge the financial support from the Zhejiang Provincial Key Laboratory of Laser Processing Robot/Key Laboratory of Laser Precision Processing and Detection (No. lzsy-09) and the Major Science and Technology Project of Wenzhou Science and Technology Bureau (ZG2017030).


  1. 1.
    X. Sun, Research on Annealing Processes and Properties of 40CrNiMo Steel. Met. Prod., 2014, 40, p 19–22.Google Scholar
  2. 2.
    M.A. Wei, Surface Heat Treatment Process of Steel 40CrNiMo Used for Gear Shaft. Foundry Technol., 2014, 35, p 2252–2254.Google Scholar
  3. 3.
    X. Zhang, Q. Wang, T. Chen, and L. Wang, Research on Strengthening Mechanism of 40CrNiMo Steel Sub-temperature Quenching, Hot Work. Technol., 2012, 22, p 218–220Google Scholar
  4. 4.
    K. Dejun and Z. Lei, Effects of Laser Quenching on Impact Toughness and Fracture Morphologies of 40CrNiMo High Strength Steel, J. Mater. Eng. Perform., 2015, 23, p 3695–3702CrossRefGoogle Scholar
  5. 5.
    Z.G.W. Mei-Qin, Study on Deformation and Ion Implantation Compound-Intensity of 40CrNiMo Steel, Hot Work. Technol., 2006, 5, p 3Google Scholar
  6. 6.
    S. Zabeen, K. Langer, and M.E. Fitzpatrick, Effect of Texture on the Residual Stress Response from Laser Peening of an Aluminium–Lithium Alloy, J. Mater. Process. Technol., 2017, 251, p 251Google Scholar
  7. 7.
    S.S. Hassan, M.N. Hamzah, and R.M. Abed, The Effect of Laser Shock Peening on Fatigue Life Using Pure Water and Hydrofluoric Acid as a Confining Layer of Al-Alloy 7075-T6, Univ. Baghdad Eng. J., 2018, 24, p 207–217Google Scholar
  8. 8.
    L.J. Wu, K.Y. Luo, Y. Liu, C.Y. Cui, W. Xue, and J.Z. Lu, Effects of Laser Shock Peening on the Micro-hardness, Tensile Properties, and Fracture Morphologies of CP-Ti Alloy at Different Temperatures, Appl. Surf. Sci., 2017, 431, p 122CrossRefGoogle Scholar
  9. 9.
    M. Kattoura, S.R. Mannava, D. Qian, and V.K. Vasudevan, Effect of Laser Shock Peening on Residual Stress, Microstructure and Fatigue Behavior of ATI, 718Plus Alloy, Int. J. Fatigue, 2017, 102, p 121–134CrossRefGoogle Scholar
  10. 10.
    M. Li, Z. Yongqiao, H. Xing, and Z. Henghua, Effect of Banded Carbides on the Wear Resistance of GCr15 Bearing Steel, ShangHai Met., 2017, 25, p 49–53Google Scholar
  11. 11.
    C. Zhang, Y. Hua, W. Shuai, and Z. Li, Effect of Laser Shot Peening on Microstructure and Residual Stress of WC-Co Cemented Carbide, Surf. Technol., 2018, 15, p 230–235Google Scholar
  12. 12.
    M.A. Meyers, O. Vohringer, and V.A. Lubarda, The Onset of Twinning in Metals: A Constitutive Description, Acta Mater., 2001, 49, p 4025–4039CrossRefGoogle Scholar
  13. 13.
    Q. Yu, Z.W. Shan, J. Li et al., Strong Crystal Size Effect on Deformation Twinning, Nature, 2010, 463, p 335–338CrossRefGoogle Scholar
  14. 14.
    K.S. Kumar, H. Van Swygenhoven, and S. Suresh, Mechanical Behavior of Nanocrystalline Metals and Alloys, Acta Mater., 2003, 51, p 5743–5774CrossRefGoogle Scholar
  15. 15.
    G. Chen, X. Zhang, and R. Yu, Effect of Zonal Segregation on Microstructure and Mechanical Properties of 40CrNIMO Steel, Mater. Heat Treat., 2012, 8, p 16–18Google Scholar
  16. 16.
    Y. Lu, J. Zhao, H. Qiao, and B. Sun, Strengthening Mechanism of TC17 Titanium Alloy Warm Laser Shock Peening, Surf. Technol., 2018, 47, p 1–7Google Scholar

Copyright information

© ASM International 2019

Authors and Affiliations

  • Huan Chen
    • 1
    • 2
  • Aixin Feng
    • 1
    • 2
    Email author
  • Jing Li
    • 1
    • 2
    • 3
  • Tiandai Jia
    • 1
    • 2
  • Yong Liu
    • 1
    • 2
  1. 1.College of Mechanical and Electrical EngineeringWenzhou UniversityWenzhouPeople’s Republic of China
  2. 2.Zhejiang Provincial Key Laboratory of Laser Processing Robot/Key Laboratory of Laser Precision Processing and DetectionWenzhouPeople’s Republic of China
  3. 3.School of Mechanical EngineeringJiangsu UniversityZhenjiangPeople’s Republic of China

Personalised recommendations