Abstract
An experimental protocol was developed to achieve complete energy balances associated with low cycle fatigue (LCF) of a polyamide 6.6 matrix (PA6.6). The protocol involves quantitative infrared techniques (IRT), and digital speckle image correlation (DIC). IRT data were used with a local heat diffusion equation to estimate strain-induced heat sources, namely dissipation and coupling sources, while DIC enabled strain and stress assessments. Both techniques were then successfully combined to quantify deformation, dissipated and stored energies and then to estimate the Taylor-Quinney ratio that is widely used in plasticity.
In this paper, the effects of loading frequency and relative humidity were investigated. It was shown that an increase of relative humidity resulted in a decrease in the mean stored energy rate per cycle, while the stored energy ratio was much smaller at low than at high loading frequency. In addition, it was found that this ratio could be negative at the last fatigue stage, just before macroscopic crack inception. These energy properties will act safeguards for the future development of a thermomechanical model of PA6.6 matrix behavior.
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References
Farren WS, Taylor GI (1925) The heat developed during plastic extension of metals. Proc R Soc A 107:422–451
Taylor GI, Quinney H (1934) The latent energy remaining in a metal after cold working. Proc R Soc A 14(3):307–326
Williams RO (1967) In: Herman H (ed) Experimental methods of materials research, vol 1. Interscience, New York, NY
J. S. LI. Leach (1970) Physicochemical measurements in metals research, vol 4. R.A. Rapp (ed) Interscience, New York, NY
Chrysochoos A (1985) Energy balance for elastic plastic deformation at finite strain (in French). J Theor Appl Mech 5:589–614
Chrysochoos A, Maisonneuve O, Martin G, Caumon H, Chezeaux JC (1989) Plastic and dissipated work and stored energy. Nucl Eng Des 114:323–333
Mason J, Rosakis A, Ravichandran G (1994) On the strain and strain rate dependence of the fraction of plastic work converted to heat: : an experimental study using high speed infrared detectors and the Kolsky bar. Mech Mater 17:135–145
Rittel D (1999) On the conversion of plastic work to heat during high strain rate deformation of glassy polymers. Mech Mater 31:131–139
Rosakis P, Rosakis AJ, Ravichandran G, Hodowany J (2000) A thermodynamic internal variable model for the partition of plastic work into heat and stored energy in metals. J Mech Phys Solids 48:581–607
Oliferuk W, Maj M, Raniecki B (2004) Experimental analysis of energy storage rate components during tensile deformation of polycrystals. Mater Sci Eng A 374:77–81
Halphen B, Nguyen QS (1975) On the generalized standards materials (in French). Journal de Mécanique 14(I):39–63
Chrysochoos A, Louche H (2000) An infrared image processing to analyse the calorific effects accompanying strain localisation. Int J Eng Sci 38:1759–1788
Berthel B, Chrysochoos A, Wattrisse B, Galtier A (2008) Infrared image processing for the calorimetric analysis of fatigue phenomena. Exp Mech 48:79–90
Honorat V, Moreau S, Muracciole JM, Wattrisse B, Chrysochoos A (2005) Calorimetric analysis of polymer behaviour using a pixel calibration of an IRFPA camera. Qirt J 2:153–171
Boulanger T, Chrysochoos A, Mabru C, Galtier A (2004) Calorimetric analysis of dissipative and thermoelastic effects associated with the fatigue behavior of steels. Int J Fatigue 26:221–229
Wattrisse B, Chrysochoos A, Muracciole J-M, Némoz-Gaillard M (2001) Analysis of strain localization during tensile tests by digital image correlation. Exp Mech 41:29–39
Dillon OWJ (1966) The heat generated during the torsional oscillations of copper tubes. Int J Solids Struct 2:181–204
Benaarbia A, Chrysochoos A, Robert G (2014) Kinetics of stored and dissipated energies associated with cyclic loadings of dry polyamide 6.6 specimens. Polym Test 34:155–167
Oliferuk W, Korbel A, Bochniak W (2001) Energy balance and macroscopic strain localization during plastic deformation of polycrystalline metals. Mater Sci Eng A 319:250–253
Acknowledgements
The authors gratefully acknowledge Solvay Engineering Plastics for supporting this work and for providing material data and specimens. This work benefited from the financial support of the French Minister for Research (ANRT) and was performed in the framework of the European DURAFIP project
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Benaarbia, A., Chrysochoos, A., Robert, G. (2015). Influence of Relative Humidity on the Thermomechanical Behavior of PA6.6. In: Sottos, N., Rowlands, R., Dannemann, K. (eds) Experimental and Applied Mechanics, Volume 6. Conference Proceedings of the Society for Experimental Mechanics Series. Springer, Cham. https://doi.org/10.1007/978-3-319-06989-0_23
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DOI: https://doi.org/10.1007/978-3-319-06989-0_23
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