Publisher : The Korean Society for Technology of Plasticity
DOI : 10.5228/KSTP.24.6.411
Title & Authors
Hot Forging of an Engine Piston using Control Cooling Lee, S. I.; Choi, D. H.; Lee, J. H.;
The piston engine is an essential component in automobiles. Since the piston is used in a high temperature and high pressure environment, the piston needs to be manufactured to achieve high strength and high durability. In addition, cost reduction is also an important consideration. In conventional forging, an additional heat treatment after hot forging is necessary to ensure proper mechanical properties for heavy-duty engine pistons. The newly developed manufacturing method lowers production costs by saving manufacturing time and reduces energy consumption. The current paper describes the hot forging of an engine piston made from 38MnSiVS5 micro-alloyed steel using controlled cooling. The finite element analysis was used to check for possible problems and suitable press capacity. Hot forging experiments were then conducted on a 2500tons crank press to evaluate feasibility of the proposed material and process. To check the mechanical properties after hot forging, the forged specimens were tensile tested, and the microstructures were examined in order to compare the results with the conventionally forged material. The skirt region of the as-forged 38MnSiVS5 piston showed better material properties compared to the conventional material. In addition, the total production time was reduced by about 80% as compared to conventional forging.
Control Cooling;Hot Forging;Piston;Mechanical Properties;Finite Elements Method(FEM);
Y. H. Kim, W. B. Bae, H. S. Kim, H. S. Byun, 1998, An Experimental Study on the Manufacturing Technology of an Engine Piston, J. Korean. Soc. Precis. Eng., Vol. 15, No. 11, pp. 83~92.
H. Y. You, 2012, A Study on the Forming Conditions of a Forging Piston by using the Finite Element Simulation and the Taguchi Method, J. Korea. Acad. Industr. Coop. Soc., Vol. 13, No. 5 pp. 1990~1995.
S. Y. Lee H. Kim, 2012, Development of Chassis Parts Using High Toughness Micro-alloyed Steel, Transactions of KSAE, Vol. 20, No. 3, pp. 1~6.
D. L. Lee, 2002, The Current Status of the Development of Heat-Treatment-Free Steel, Trans. Mater. Process., Vol. 11, No. 5, pp. 398~393.
X. Huang, C. Liu, X Lv, G. Liu, F. Li, 2011, Aluminum Alloy Pistons Reinforced with SiC Fabricated by Centrifugal Casting, J. Mater. Process. Tech., Vol. 211, No. 9, pp. 1540~1546.
G. Dini, M. M. Vaghefi, A. Shafyei, 2006, The Influence of Reheating Temperature and Direct-cooling Rate after Forging on Microstructure and Mechanical Properties of V-microalloyed Steel 38MnSiVS5, ISIJ Int., Vol. 46, No. 1, pp. 89~92.
N. G. Kim, S. D. Park, B. O. Kim, J. Y. An, H. J. Choi, 2006, Study of Material Properties of High Strength Microalloyed Steel for Cold Forming by Controlled Rolling and Cooling Technology, Trans. Mater. Process., Vol. 15, No. 8, pp. 603~608.
D. J. Yoon, H. J. Choi, H. W. Lee, G. A. Lee, B. L. Jang, S. L. Seo, S. Choi, 2006, Net Shape Forming Process for Ball Stud Using High Strength Micro-Alloyed Cold Forging Steel, Trans. Mater. Process., Vol. 15, No. 8, pp. 562~567.
J. H. Son, M. Y. Ha, S. C. Ahn, S. W. Choi, 2010, Durability Design of Composite Piston in Marine Diesel Engines, Trans. Kor. Soc. Mech. Eng. A, Vol. 34, No. 5, pp. 651~657.
M. I. Najafabadi, M. Mirsalim, V. Hosseini, S. Alaviyoun, 2014, Experimental and Numerical Study of Piston Thermal Management using Piston Cooling Jet, J. Mech. Sci. Technol., Vol. 28, No. 3, pp. 1079~1087.
S. H. Yeom, B. S. Lee, B. R. Rho, S. I. Hong, 2004, A Study on Forging Process about Preform of Articulated Piston for Diesel Engine, Trans. Mater. Process., Vol. 13, No. 7, pp. 635~641.
S. H. Yeom, K. O. Nam, D. S. Hwang, H. S. Kwon, S. I. Hong, 2006, A Study on the Process Development of Mono Steel Forged Piston for Diesel Engine, Trans. Korean. Soc. Automot. Eng., Vol. 14. No. 3, pp. 44~50.