Effect of Laser Preheating AISI 4140 Specimens for Micro-Forging

• Autorzy: Jung C. , Lee M. G. , Jeon Y.

Identyfikatory

DOI

10.1515/amm-2017-0179

• Języki publikacji: EN

Abstrakty

EN

Many high performance and permanent service parts require suitable material characteristics-high fatigue strength is one of the most important characteristics. For this reason, surface treatment processes are essential to increase the material performance and avoid the use of costly ineffective material. There exist various surface treatment processes for various applications. Each process has advantages and disadvantages and hybridization can solve various problems. The micro-forging process delivers a controlled and uniform surface hardness, but the depth of the forged surface is limited. On the other hand, laser heat treatment can increase the hardness drastically, but the surface may become brittle, which reduces the fatigue life. Laser-assisted micro-forging is a novel hybrid process of laser heat treatment and micro-forging that has the potential to increase the forging depth and relax the stress caused by the high temperature of the forging process. This study examines the effect of laser preheating in the micro-forging of AISI 4140. The processes were varied as follows: no treatment, micro-forging only, and laser-assisted micro-forging. The fatigue strength of the specimens was examined by means of an ultrasonic fatigue tester and then compared. The microstructural changes were investigated with respect to the processes by using scanning electron microscopy. In conclusion, it was confirmed that the laser preheating auxiliary forging affects the fatigue life. It was confirmed that the fatigue life was the mostly increased in 550°C temperature laser preheating micro forging process and the temperature was identified as the most important factor.

Słowa kluczowe

EN

laser preheating; micro-forging; fatigue strength; ultrasonic fatigue test; hardness

• Wydawca: Institute of Metallurgy and Materials Science of Polish Academy of Sciences ; Committee of Materials Engineering and Metallurgy of Polish Academy of Sciences
• Czasopismo: Archives of Metallurgy and Materials
• Rocznik: 2017
• Tom: Vol. 62, iss. 2B
• Strony: 1209--1213
• Opis fizyczny: Bibliogr. 8 poz., rys., tab.

Twórcy

autor

Jung C.

• Department of Mechanical Engineering, Ajou University, Suwon, 443-749, Korea (Republic of)

autor

Lee M. G.

• Department of Mechanical Engineering, Ajou University, Suwon, 443-749, Korea (Republic of)

autor

Jeon Y.

• Department of Mechanical Engineering, Ajou University, Suwon, 443-749, Korea (Republic of)

Bibliografia

• [1] B. J. Choi, Y. Jeon, M. G. Lee, H. J. Kim, D. K. Kim, Analysis of Micro Forging System for Straightness of Vibration Tip. Korea society for precision engineering 2016 autumn conference, 863-863. (2015).
• [2] C. H. Jung, M. G. Lee, J. N. Park, Y. Jeon, FEM simulation and experimental validation of residual stress on surface by micro forging processes, International Conference on Surface Modification Technologies (2016).
• [3] W. S. Lee, G. W. Yeh, The Plastic Deformation Behavior of AISI 4340 Alloy Steel Subjected to High Temperature and High Strain Rate Loading Conditions, Journal of Materials Processing Technology 71.2, 224-34 Web. (1997).
• [4] http://www.etrema.com/cu18a-ultrasonic-actuator.
• [5] K. Dai, L. Shaw, Comparison between shot peening and Surface nanocrystallization and hardening processes, Materials Science and Engineering A 463 (1-2), 46-53 (2007).
• [6] M. C. Oh, H. Yeom, Y. Jeon, B. Ahn, Microstructural Characterization Of Laser Heat Treated AISI 4140 Steel With Improved Fatigue Behavior, Archives of Metallurgy and Materials 60, 2 (2015).
• [7] Y. Furuya, H. Hirukawa, T. Kimura, M. Hayaishi, Gigacycle Fatigue Properties of High-Strength Steels According to Inclusion and ODA Sizes, Metall. and Mat. Trans. A 38 (8), 1722-1730 (2007). doi:10.1007/s11661-007-9225-3.
• [8] M. L. Bauccio, Materials Park, ASM engineering materials reference book, OH: ASM, 1994.

Uwagi

EN

Opracowanie ze środków MNiSW w ramach umowy 812/P-DUN/2016 na działalność upowszechniającą naukę (zadania 2017)