Determination of Fatigue Limit by Locati Methodusing S-N Curve Determined by Means of Thermographic Method

Abstract:

Selected results of experimental research showing possibilities to combined accelerated methods, i.e. thermographic determination of the fatigue curve and estimating the fatigue limit, were presented in this paper. The tests were performed using the reversed bending fatigue-testing machine with a rotational frequency of 77 Hz. The main item of the test station was the thermographic camera. Test specimens were made of C45 (1.0503) steel drawn bars. The full tests results were presented for the fatigue S-N curve (23 specimens at 10 load levels) and fatigue limit by the Staircase method (25 specimens) based on 10⁷ cycles to failure was determination. The accelerated test for determining the slope of the S-N curve and the fatigue limit were made by a single specimen based on gradually increasing loading. Methods previously presented in the literature are based on the phenomenon of temperature stabilization during most of the fatigue process. The results presented in this work did not show the occurrence of such a phenomenon. For that reason, the new approach to the determination of the slope of S-N curve was proposed. Combined application of both experimental methods, Locati and thermographic, with a new approach to the determination of this slope might allow one to develop automatic equipment for the accelerated determination of the fatigue limit which would contribute to significant reduction of the test costs and time, thus increasing availability of such tests.

• Periodical: Solid State Phenomena (Volume 223)
• Pages: 362-373
• DOI: https://doi.org/10.4028/www.scientific.net/SSP.223.362
• Online since: November 2014
• Authors: Adam Lipski*
• Keywords: Fatigue Limit, IR Thermography, Locati Method, Reversed Bending, Staircase Method

References

[1] W.J. Dixon, The Up-and-Down Method for Small Samples, Journal of the American Statistical Association. Vol. 60, No. 312 (1965), p.967–978.

DOI: 10.1080/01621459.1965.10480843

[2] W.J. Dixon, A.M. Mood, A Method for Obtaining and Analyzing Sensitivity Data, Journal of the American Statistical Association. Vol. 43, No. 241 (1948), p.109–126.

DOI: 10.1080/01621459.1948.10483254

[3] K.A. Brownlee et al., The Up-and-Down Method with Small Samples, Journal of the American Statistical Association. Vol. 48, No. 262 (1953), p.262–277.

DOI: 10.1080/01621459.1953.10483472

[4] H. Nakazawa, K. Shotaro, Statistical S-N Testing Method with 14 Specimens: JSME Standard Method for Determination of S-N Curves. Statistical Research on Fatigue and Fracture. Japan Society of Materials Science, Elsevier, New York, (1987).

[5] J.A. Collins, Failure of materials in mechanical design - analysis, prediction, prevention. John Wiley & Sons, New York, (1993).

[6] J. Zhang, D.B. Kececioglu, New approaches to determine the endurance strength distribution. 4th ISSAT International Conference on Reliability & Quality in Design , Seattle, (1998).

[7] D. Radaj, Design and Analysis of Fatigue Resistant Welded Structures. Woodhead Publishing Ltd., (1990).

[8] R. Litwinko, W. Oliferuk, Yield Point Determination Based On Thermomechanical Behaviour Of Polycrystalline Material Under Uniaxial Loading, Acta Mechanica et Automatica, Vol. 3, No. 4 (2009), pp.49-51.

[9] A. Lipski, The use of passive infrared thermography for tests of materials and riveted joints used in aviation industry- selected problems. Part II of the collection of monographs (edited by J. Szala): Experimental methods in studies of materials and riveted joints used in aviation industry - selected problems. Institute For Sustainable Technologies – National Research Institute in Radom, Bydgoszcz-Radom, 2010 (in Polish).

[10] A. Lipski, Impact Of The Strain Rate During Tension Test On 46Cr1 Steel Temperature Change, Key Engineering Materials, Vol. 598 (2014), pp.133-140.

DOI: 10.4028/www.scientific.net/kem.598.133

[11] M. Poncelet et al., Probabilistic multiscale models and measurements of self-heating under multiaxial high cycle fatigue, Journal of Mechanics and Physics of Solids, Vol. 58, No. 4 (2010), p.578–593.

DOI: 10.1016/j.jmps.2010.01.003

[12] C. Doudard et al., Determination of an HCF criterion by thermal measurements under biaxial cyclic loading, International Journal of Fatigue, Vol. 29, No. 4 (2007), p.748–757.

DOI: 10.1016/j.ijfatigue.2006.06.009

[13] A. Lipski, D. Skibicki, Variations Of The Specimen Temperature Depending On The Pattern Of The Multiaxial Load - Preliminary Research, Materials Science Forum, Vol. 726 (2012), pp.162-168.

DOI: 10.4028/www.scientific.net/msf.726.162

[14] D. Skibicki, J. Sempruch, A. Lipski, Ł. Pejkowski, Fatigue Life, Fractographic and Thermographic Analysis of Steel X2CrNiMo17-12-2 for Proportional and Non-Proportional Loads, The Tenth International Conference on Multiaxial Fatigue & Fracture, Kyoto (Japan), (2013).

DOI: 10.4028/www.scientific.net/msf.726.171

[15] A. Lipski, D. Boroński, Use of Thermography for the Analysis of Strength Properties of Mini-Specimens, Materials Science Forum, Vol. 726 (2012), pp.156-161.

DOI: 10.4028/www.scientific.net/msf.726.156

[16] G. La Rosa, A. Risitano, Thermographic methodology for rapid determination of the fatigue limit of materials and mechanical components, International Journal of Fatigue, Vol. 22, No. 1 (2000), p.65–73.

DOI: 10.1016/s0142-1123(99)00088-2

[17] G. Meneghetti, Analysis of the fatigue strength of a stainless steel based on the energy dissipation, International Journal of Fatigue, Vol. 29, No. 1 (2007), pp.81-94.

DOI: 10.1016/j.ijfatigue.2006.02.043

[18] M.P. Luong, Fatigue limit evaluation of metals using an infrared thermographic technique, Mechanics of Materials, Vol. 28, No. 1 (1998), p.155–163.

DOI: 10.1016/s0167-6636(97)00047-1

[19] F. Cura, G. Curti, R. Sesana, A new iteration method for the thermographic determination of fatigue limit in steels, International Journal of Fatigue, Vol. 27, No. 4 (2005), p.453–459.

DOI: 10.1016/j.ijfatigue.2003.12.009

[20] X.G. Wang, V. Crupi, X.L. Guo, Y.G. Zhao, Quantitative Thermographic Methodology for fatigue assessment and stress measurement, International Journal of Fatigue, Vol. 32, No. 12 (2010), p.1970–(1976).

DOI: 10.1016/j.ijfatigue.2010.07.004

[21] G. Fargione et al., Rapid determination of the fatigue curve by the thermographic method, International Journal of Fatigue, Vol. 24, No. 1 (2002), p.11–19.

DOI: 10.1016/s0142-1123(01)00107-4