Energy balance of thermoelastic martensite transformation under stress

A specific device for enhanced measurement of mechanical dissipation in specimens subjected to long‐term tensile tests in fatigue

“…The application to rubber is typical of the relevance of the approach in studying various material responses: [12][13][14][15][16][17] thermoelastic coupling, entropic coupling, thermoelastic inversion, the effect of reinforcement by fillers, strain-induced crystallization, and the Mullins effect. The 0D approach has been also applied to study the thermomechanical response of SMAs under cyclic loading, [7,[18][19][20][21][22] as well as polyamide 6.6, [23][24][25][26][27] aluminum alloy, [28] and steel. [29] However, a difficulty arises for the estimation of mechanical dissipation in the case of long-term cyclic tests: The results are easily skewed by any change in the specimen's environment, such as the ambient air, the grips of the testing machine, and more generally, all the components of the testing room.…”

“…The problem is amplified by the fact that mechanical dissipation is in general small compared to the part of the heat sources associated with the thermomechanical couplings, such as thermoelastic coupling or solid-solid phase transformation. [18,30] This paper proposes a simple methodology to extract a well-resolved estimation of mechanical dissipation by solving two key points specific to long-term cyclic tests:…”

Thermoelastic analysis of a copper-based monocristalline shape-memory alloy

“…Normalised temperature amplitude = 'T / 'V macro (4) With isotropic materials, Equation (3) shows that the normalised temperature amplitude would be equal to DT 0 /UC; so its value would be specific to the considered material and phase.…”

“…Thermomechanical couplings play an important role in the response of the material under mechanical load, even at constant room temperature [1][2][3][4][5][6][7][8][9][10][11][12]. Some other thermal effects are related to the thermoelastic coupling, also named isentropic coupling, which is the coupling between the temperature and the elastic part of the strain through the coefficient of thermal expansion (CTE) appearing in the free energy expression [13].…”

Fatigue assessment by energy approach during tensile tests on AISI 304 steel

“…In 2014 [11], Crupi et al were the first researchers that detected the radiometric surface temperature during ultrasonic fatigue tests in order to extend the thermographic method in very high cycle fatigue regime. Chrysochoos et al in [12] have determined experimentally the energy balances of pseudo-elastic behaviour of a shape memory alloy using IR techniques and in [13], using infrared image processing, have determined the evolution of the heat source's distribution on steel samples during monotone tension tests. The same authors in [14] presented an infrared data processing developed to analyse the calorific manifestations accompanying elastoplastic transformation during tensile tests.…”