Effects of stress triaxiality ratio on the heat build-up of polyamide 11 under loading. (June 2020)

• Record Type: Journal Article
• Authors: Ovalle, C.; Boisot, G.; Laiarinandrasana, L.
• Is Part Of: Mechanics of materials. Volume 145(2020)
• Publication Date: 2020-06
• Subjects: Polymers -- Damage mechanics -- Fracture mechanics -- Finite element analysis -- Thermo-mechanical coupling -- Heat build-up; Strength of materials -- Periodicals; Mechanics, Applied -- Periodicals; Résistance des matériaux -- Périodiques; Mécanique appliquée -- Périodiques; Mechanics, Applied; Strength of materials; Periodicals; Electronic journals; 620.11
• DOI: 10.1016/j.mechmat.2020.103375
• Languages: English
• ISSNs: 0167-6636

Abstract

Highlights: Stress triaxiality ratio effects on the adiabatic heating of a PA11 under monotonic loading were investigated Temperature-dependent response of a PA11 at different crosshead speeds Temperature-dependent GTN-based model extended to account for the plastic work converted to heat Predictive capabilities for other stress triaxiality ratios and geometries Abstract: Adiabatic heat build-up in polymers attributed to the conversion of plastic work into dissipative heat is a well known phenomenon. The temperature in the vicinity of a crack tip due to heat build-up may be exceptionally high so that it can locally reach the glass transition temperature T g, even though the ambient testing temperature is lower than T g . A significant alteration of the local material response and damage mechanisms is then induced. By simultaneous measurement of temperature during experimental tests under quasi-static loading and for a wide range of stress triaxiality ratios, a Gurson-Tvergaard-Needleman based thermo-mechanical constitutive model, integrating temperature-dependent coefficients, has been developed. Predictive capabilities of the proposed thermo-mechanical model to simulate the isothermal behaviour of PolyAmide 11 (PA11) have led to adiabatic simulations, to account for the heat build-up highlighted experimentally, of ductile crack extension. The model parameters were identified using experimental data obtained from PA11 samples with a given stress triaxiality ratio. Predicted evolutions given by the proposed constitutive model for other stress triaxiality ratios and geometries are found to be in good agreement with experimental data.