Hardness prediction of a cold rolled Nimonic 80A exhaust valve spindle

• Autorzy: Kang S. W. , Heo S. J. , Yoo J. H. , Kang J. H.

Identyfikatory

DOI

10.5604/01.3001.0013.5117

• Języki publikacji: EN

Abstrakty

EN

Purpose: of this paper is to predict the hardness of cold rolled exhausts valve spindle fabricated of Nimonic 80A via axisymmetric finite element analysis, compression testing, and hardness inspection. Design/methodology/approach: The stress-strain relationship of Nimonic 80A was obtained via compression testing with deformation ratios of 10%, 20%, and 30%. Hardness changes caused by the strain hardening effect were measured in cut specimens in both the axial and circumferential directions following compression testing. The effective strain at the measurement position was calculated via finite element analysis. The regression equation for hardness changes caused by work hardening was derived from analysed strain and inspected hardness. The cold-rolling deformation of an exhaust valve spindle was analysed using axisymmetric finite element analysis. Findings: The stress-strain relationship calculated from compression testing was well expressed using the Holloman equation and the strain-hardness relationship by strain hardening was successfully regressed using the shifted power law model for Nimonic 80A, Nickel-Chromium based super alloy. Research limitations/implications: This research focused hardness prediction of spindle after ring rolling operation for generating beneficial compressive surface residual stresses for enhancing fatigue life. Further research to quantify compressive residual stress after rolling shall be followed to increase fatigue life. Practical implications: The cold rolling process is a typical incremental forming method and should be analysed under three-dimensional conditions. However, it takes lots of time to solve incremental forming analysis. To predict hardness distribution after rolling in the manufacturing field, FE analysis was performed under two-dimensional axisymmetric conditions based on the assumption of no friction generated by the rolling tool. The deformed shapes and hardness distribution from the inspection quality standard and two-dimensional FE analysis showed very similar results. Simplified finite element analysis method for ring rolling process for local area could be very effective method in the industrial field. Originality/value: The stress-strain relationship and the hardness and strain relationship were derived by compression test and hardness measurement for compressed specimen for Nimonic 80A, Nickel-Chromium based super alloy. And simplified finite element analysis method was suggested to predict deformed shape and hardness distribution of locally cold rolled region and achieved similar result between FE analysis result and Quality standard. Suggested method would be very effective method to engine spindle manufacture to predict hardness of different size of product.

Słowa kluczowe

EN

Nimonic 80A; exhaust valve; stress-strain curve; hardness prediction; finite element method

PL

Nimonic 80A; zawór wylotowy; krzywa naprężenie-odkształcenie; metoda elementów skończonych

• Wydawca: International OCSCO World Press
• Czasopismo: Journal of Achievements in Materials and Manufacturing Engineering
• Rocznik: 2019
• Tom: Vol. 94, nr 1-2
• Strony: 13--21
• Opis fizyczny: Bibliogr. 14 poz., rys., tab., wykr.

Twórcy

autor

Kang S. W.

• Friend Co. LTD, 9, Gwahaksandan-ro 333beon-gil, Busan, 46749, Korea

autor

Heo S. J.

• Graduate School, Department of Convergence Engineering, Jungwon Univ., 85, Munmuro, Chungbuk, 28024, Korea

autor

Yoo J. H.

• Graduate School, Department of Convergence Engineering, Jungwon Univ., 85, Munmuro, Chungbuk, 28024, Korea

autor

Kang J. H.

• Department of Aero-Mechanical Engineering, Jungwon Univ., 85, Munmuro, Chungbuk, 28024, Korea

Bibliografia

• [1] U.D. Bihlet, H.A. Hoeg, Future HFO/GI exhaust valve spindle, Proceedings of the 27th CIMAC World Congress on Combustion Engine Technology, Shanghai, China, 2013.
• [2] J.V. Carstensen, Wear loaded components in large ship diesel engines, MAN Diesel & Turbo, 2012.
• [3] MAN B&W S50ME-B9.5-TII Project Guide Electronically Controlled Two stroke Engines with Camshaft Controlled Exhaust Valves, MAN Diesel & Turbo, 2016.
• [4] H. Fellmann, T. Groß, T. Ludwig, Typical wear mechanism of 2-stroke exhaust valves, Proceedings of the Marine Propulsion Conference, 2004.
• [5] N. Vardar, A. Ekerim, Investigation of Exhaust Valve Failure in Heavy-duty Diesel Engine, Gazi University Journal of Science 23/4 (2010) 493-499.
• [6] S.H. Jang, J.H. Choi, Study on reconditioning the exhaust valve of a two-stroke diesel engine, Journal of the Korean Society of Marine Engineering 41/6 (2017) 489-494, DOI: https://doi.org/10.5916/jkosme.41.6.489.
• [7] L.J. Ebert, Fatigue Resistance of Steels, in: Volume 1: Properties and Selection: Irons, Steels, and High-Performance Alloys, ASM Handbook, 1990, 673-688.
• [8] A. Fatemi, Chapter 8 - Residual Stresses & Their Effects, University of Toledo, Available at: https://www.efatigue.comitraining/Chapter_8.pdf.
• [9] M. Matsuda, E. Ootsuki, S. Kajihara, Y. Hanawa, T. Hamada, Predicting Effect of Cold Rolling on Fatigue Strength under Combined Loading, Kobelco Technology Review 30 (2011) 7-12.
• [10] T. Hanaki, Y. Hayashi, H. Akebono, M. Kato, A. Sugeta, Effect of compression Residual Stress on Fatigue Properties of Stainless Cast Steel, Procedia Structural Integrity 2 (2016) 3143-3149, DOI: https://doi.org/10.1016/j.prostr.2016.06.392.
• [11] H.K. Kim, S.M. Lee, T. Altan, Prediction of hardness distribution in cold backward extruded cups, Journal of Materials Processing Technology 59/15 (1996) 113-121, DOI: https://doi.org/10.1016/0924-0136(96)02292-3.
• [12] H. Tumer, F.O, Sonmez, Optimum shape design of die and preform for improved hardness distribution in cold forged parts, Journal of Materials Processing Technology 209 (2009) 1538-1549, DOI: https://doi.org/10.1016/j.j matprotec.2008.04.017.
• [13] A. Demir, F.O. Sonmez, Prediction of Brinell Hardness Distribution in Cold Formed Parts, Transactions of the ASME 126 (2004) 398-405, DOI: https://doi.org/10.1115/1.1789960.
• [14] Exhaust valve spindle inspection and acceptance criteria, Man Diesel & Turbo, 2016.

Uwagi

PL

Opracowanie rekordu w ramach umowy 509/P-DUN/2018 ze środków MNiSW przeznaczonych na działalność upowszechniającą naukę (2019).