Sensitivity analysis in life prediction of extrusion dies

• Autorzy: Qamar S. Z. , Pervez T. , Siddiqui R. A. , Sheikh A. K. , Arif A. F. M.
• Języki publikacji: EN

Abstrakty

EN

Purpose: Building up on the fracture mechanics (Paris law for crack propagation) based fatigue life prediction model developed earlier by the authors, Monte Carlo simulation has been performed to evaluate sensitivity of die life related to important geometrical and material parameters. Stochastic nature of various fatigue-related die parameters is used to reflect their variability. Design/methodology/approach: Life of the die is one of the most important factors affecting productivity and profitability in hot extrusion of metals. It has been reported in earlier works by the authors that extrusion dies most often fail by fatigue fracture. Experimental studies have shown that cracks preexist in dies due to various factors including heat treatment, machining, and surface hardening. High levels of repeated mechanical and thermal loads result in crack propagation leading to ultimate fracture failure. Findings: Findings of the sensitivity analysis are that fracture life of an extrusion die is very sensitive to initial crack size, section thickness, profile outer diameter and billet length; moderately sensitive to Paris constant and extrusion ratio; and only slightly sensitive to fracture toughness and ram speed. Practical implications: The study can be of direct utility in extrusion die design improvement, formulation of an optimum die replacement strategy, etc. Originality/value: The paper provides basis for a deeper understanding of the factors responsible for fracture failure of an extrusion die exposed to thermo-mechanical fatigue environment.

Słowa kluczowe

EN

sensitivity analysis; die life; fracture failure; extrusion die; Monte Carlo simulation

PL

analiza wrażliwości; trwałość matrycy; pęknięcie; uszkodzenie; defekt; formowanie wytłoczne; symulacja Monte Carlo; SMC

• Wydawca: International OCSCO World Press
• Czasopismo: Journal of Achievements in Materials and Manufacturing Engineering
• Rocznik: 2007
• Tom: Vol. 25, nr 1
• Strony: 49--54
• Opis fizyczny: Bibliogr. 14 poz., rys., tab.

Twórcy

autor

Qamar S. Z.

autor

Pervez T.

autor

Siddiqui R. A.

autor

Sheikh A. K.

autor

Arif A. F. M.

• Mechanical and Industrial Engineering Department, Box 33, Sultan Qaboos University, Al Khoudh 123, Sultanate of Oman,

Bibliografia

• [1] A.F.M. Arif, A.K Sheikh, S.Z. Qamar, K.M. al-Fuhaid, A Study of Die Failure Mechanisms in Aluminum Extrusion, Journal of Materials Processing Technology 134 (2003) 318-328.
• [2] S.Z. Qamar, A.F.M. Arif, A.K. Sheikh, M. Younas, T. Pervez, R. A. Siddiqui, Simulation of Fatigue and Wear Life of Extrusion Dies, Proceedings of the 10th International Research/Expert Conference on "Trends in the Development of Machinery and Associated Technology" (TMT 2006), 2006, Barcelona - Lloret de Mar, Spain.
• [3] K. Pöhlandt, Materials Testing for the Metal Forming Industry, SpringerVerlag, Berlin, l989.
• [4] G. Roberts, G. Krauss, R. Kennedy, Tool Steels, ASM International Materials Park, Ohio, 1998.
• [5] R.J. Sanford, Principles of Fracture Mechanics, Pearson Education, Upper Saddle River, New Jersey, 2003.
• [6] C.C. Osgood, Fatigue Design, Pergamon Press, Oxford, 1982.
• [7] J.E. Shigley, C.R. Mischke, Budynas RG Mechanical Engineering Design, McGraw-Hill, Boston, 2004.
• [8] K.P. Groover, Fundamentals of Modern Manufacturing: Materials, Processing and Systems, John Wiley, New York, 1999.
• [9] P.K. Saha, Aluminum Extrusion Technology, ASM International, Materials Park, Ohio, 2000.
• [10] T. Sheppard, Extrusion of Aluminum Alloys, Kluwer Academic Publishers, Dordrecht, 1999.
• [11] S. Kalpakjian, Manufacturing Processes for Engineering Materials, Addison-Wesley, Menlo Park, California, 2003.
• [12] ASM, ASM Handbook Vol-19: Fatigue and Fracture, ASM International, Materials Park, Ohio, 1996.
• [13] S.Z. Qamar, A.K. Sheikh, A.F.M. Arif, T. Pervez, Regression-based CVN-KIC Models for Hot Work Tool Steels, Materials Science and Engineering 430 (2006) 208-215.
• [14] W.D. Callister, Materials Science and Engineering, An Introduction, John Wiley, New York, 2000.