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Effects of Laser Hardening Process Parameters on Case Depth of 4340 Steel Cylindrical Specimen—A Statistical Analysis

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DOI: 10.4236/jsemat.2015.53014    4,098 Downloads   4,817 Views   Citations


Laser heat treatment is considered to be one of best-performing manufacturing processes used currently due to its flexibility and its ability to develop parts with complex geometries. In fact, this process is able to produce reliable parts with hard, thin martensite and compressive residual stresses. This paper explores the heat treatment applied to 4340 cylindrical parts heated using a Nd: Yag 3 kW laser source. In this case, the hardness profile is correlated to process parameters such as the laser source power, the beam scanning speed and the revolution speed of the part during heating. Based on preliminary tests stipulating that each parameter is varied alone within a specific range, a systematic design of final tests is performed using Taguchi matrix. The obtained results are analyzed using ANOVA method to extract the effects, the contributions and the interaction between the factors. The results are then exploited to study the sensitivity of the case depth according the variation of the process parameters. The developed model exhibits good potential for converging towards a robust model able to predict the hardness curve and to generalize it for other dimensions of cylindrical parts.

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The authors declare no conflicts of interest.

Cite this paper

Barka, N. and Ouafi, A. (2015) Effects of Laser Hardening Process Parameters on Case Depth of 4340 Steel Cylindrical Specimen—A Statistical Analysis. Journal of Surface Engineered Materials and Advanced Technology, 5, 124-135. doi: 10.4236/jsemat.2015.53014.


[1] Kennedy, E., Byrne, G. and Collins, D.N. (2004) A Review of the Use of High Power Diode Lasers in Surface Hardening. Journal of Materials Processing Technology, 155-156, 1855-1860.
[2] Ricciardi, G., Cantello, M. and Micheletti, G.F. (1982) Technological Applications of the Laser Beam in Heat Treatments. CIRP Annals-Manufacturing Technology, 31, 125-130.
[3] Lakhkar, R.S., Shin, Y.C. and Krane, M.J.M. (2008) Predictive Modeling of Multi-Track Laser Hardening of AISI 4140 Steel. Materials Science and Engineering A, 480, 209-217.
[4] Patwa, R. and Shin, Y.C. (2007) Predictive Modeling of Laser Hardening of AISI5150H Steels. International Journal of Machine Tools and Manufacture, 47, 307-320.
[5] Miokovic, T., Schulze, V., Vohringer, O. and Lohe, D. (2006) Prediction of Phase Transformations during Laser Surface Hardening of AISI 4140 including the Effects of Inhomogeneous Austenite Formation. Materials Science and Engineering A, 435-436, 547-555.
[6] Ashby, M.F. and Easterling, K.E. (1984) The Transformation Hardening of Steel Surfaces by Laser Beams—I. Hypo- Eutectoid Steels. Acta Metallurgica, 32, 935-948.
[7] Tani, G., Orazi, L. and Fortunato, A. (2008) Prediction of Hypo Eutectoid Steel Softening Due to Tempering Phenomena in Laser Surface Hardening. CIRP Annals-Manufacturing Technology, 57, 209-212.
[8] Badkar, D.S., Pandey, K.S. and Buvanashekaran, G. (2011) Parameter Optimization of Laser Transformation Hardening by Using Taguchi Method and Utility Concept. International Journal of Advanced Manufacturing Technology, 52, 1067-1077.
[9] Billaud, G., Barka, N., El Ouafi, A., Chebak, A. and Brousseau, J. (2014) Prediction of Hardness Profile of 4340 Steel Plate Heat Treated by Laser Using 3D Model and Experimental Validation. ASME International Mechanical Engineering Congress and Exposition, Montreal.
[10] Komanduri, R. and Hou, Z.B. (2001) Thermal Analysis of the Laser Surface Transformation Hardening Process. International Journal of Heat and Mass Transfer, 44, 2845-2862.
[11] Janez, G. and Roman, S. (1998) Influence of Laser Surface Melt-Hardening Conditions on Residual Stresses in Thin Plates. Surface Coating Technology, 100-10, 455-458.
[12] Selvan, S.J., Subramanian, K. and Nath, A.K. (1999) Effect of Laser Surface Hardening on En18 (AISI 5135) Steel. Journal of Materials Processing Technology, 91, 29-36.
[13] Shin, H.J., Yoo, Y.T., Ahn, D.G. and Im, K. (2007) Laser Surface Hardening of S45C Medium Carbon Steel Using ND:YAG Laser with a Continuous Wave. Journal of Materials Processing Technology, 187, 467-470.
[14] Qiu, F. and Kujanpa, V. (2012) Surface Hardening of AISI 4340 Steel by Laser Linear Oscillation Scanning. Surface Engineering, 28, 569-575.
[15] Santhanakrishnan, S. and Kovacevic, R. (2012) Hardness Prediction in Multi-Pass Direct Diode Laser Heat Treatment by On-Line Surface Temperature Monitoring. Journal of Materials Processing Technology, 212, 2261-2271.
[16] Ross, P.J. (1988) Taguchi Techniques for Quality Engineering. McGraw-Hill, New York.

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