The influences of deformation state and experimental conditions on inelastic behaviour of an extruded thermoplastic polyurethane elastomer

Published Date
Materials & Design
August 2013, Vol.49:974–980, doi:10.1016/j.matdes.2013.02.055

• Author 

• Luis Bartolomé ^a,,
• Jon Aurrekoetxea ^a
• Mikel A. Urchegui ^b
• Wilson Tato ^a

• aMechanical and Manufacturing Department, Mondragon Unibertsitatea, Loramendi 4, 20500 Mondragón, Spain
• bMechanical Engineering, Orona eic S. Coop., Pol. Ind. Lastaola s/n, 20120 Hernani, Spain

Received 11 December 2012. Accepted 20 February 2013. Available online 1 March 2013. 

Abstract

Thermoplastic polyurethane elastomers under cyclic loading–unloading conditions exhibit inelastic effects, mainly stress softening, hysteresis loss and residual strain. In order to discuss the sensitivity of these effects to deformation state (uniaxial tension and pure shear) and to work conditions (maximum strain, strain-rate and stretching direction), this study is concerned with inelastic effects of an extruded thermoplastic polyurethane elastomer when is subjected to loading–unloading cycles. Based on the behaviour of inelastic effects under both tensile conditions, the present work shows that stress softening and residual strain are sensitive to deformation state only when the maximum strain reached causes permanent set. Furthermore, the hysteresis loss shows an independent behaviour depending on maximum strain. Finally, the behaviour of the hysteresis loss and the residual strain is isotropic for the extruded thermoplastic polyurethane elastomer.

Highlights

► We analyze behaviour of inelastic effects of a thermoplastic polyurethane elastomer. ► Stress softening, hysteresis loss and residual strain are the inelastic effects. ► Stress softening and residual strain are influenced by the maximum strain reached. ► Hysteresis loss exhibits a independent behaviour with maximum strain. ► The behaviour of all inelastic effects is isotropic.

Keywords

Thermoplastic polyurethane elastomer

Inelasticity

Stress softening

Hysteresis loss

Residual strain

---

Fig. 1.

Fig. 2.

 Table 1

Table 1.

Fig. 3.

 Table 2

Table 2.

Fig. 4.

Fig. 5.

Fig. 6.

Fig. 7.

Fig. 8.

Fig. 9.

Fig. 10.

Fig. 11.

Fig. 12.

Fig. 13.

Fig. 14.

• ⁎ 
  Corresponding author. Tel.: +34 943 73 96 92; fax: +34 943 71 19 12.
  
  

For further details log on website :
http://www.sciencedirect.com/science/article/pii/S0261306913001660