RT info:eu-repo/semantics/article
T1 Application of the Small Punch Creep-Recovery Test (SPCRT) for the Estimation of Large-Amplitude Viscoelastic Properties of Polymers
A1 Calaf Chica, José
A1 Bravo Díez, Pedro Miguel
A1 Preciado Calzada, Mónica
A1 García Tárrago, María José
K1 SPCRT
K1 SPT
K1 Small punch test
K1 Viscoelasticity
K1 Maxwell-Wiechert model
K1 Ingeniería eléctrica
K1 Electric engineering
K1 Ingeniería civil
K1 Civil engineering
AB The Small Punch Creep-Recovery Test (SPCRT) is a novel miniature test used to estimatethe viscoelastic properties of polymers and biomaterials. The current investigation related to theSPCRT is limited to Finite Element Method (FEM) simulations and experimental tests on PVC. Theaim of this investigation was focused on: (i) extending the experimental tests to other polymers withdissimilar viscoelastic properties; (ii) deepening the influence of non-linear viscoelastic properties inthe estimation capabilities of the SPCRT; and (iii) developing a numerical methodology to estimateand take into account the viscoelastic recovery produced during the unloading step of compressivecreep-recovery tests (CCRT) and SPCRTs. The experimental tests (CCRTs and SPCRTs) were done onpolyethylene PE 500, polyoxymethylene POM C, nylon PA 6, and polytetrafluoroethylene (PTFE),with a range of creep loads, in the case of CCRTs, in the whole elastic regime and the surroundingsof the yield strength of each material. The experimental results confirmed that the SPCRT was anaccurate and reliable testing method for linear viscoelastic polymers. For a non-linear viscoelasticbehavior, SPCRT estimated the viscoelastic properties obtained from CCRTs for creep loads near theyield strength of the polymer, which corresponded with large-amplitude viscoelastic properties indynamic creep testing. In order to consider the viscoelastic recovery generated in the unloadingstep of CCRTs and SPCRTs, a Maxwell-Wiechert model with two branches was used, simulatingthe different steps of the experimental tests, and solving numerically the differential equation of theMaxwell-Wiechert model with the Runge-Kutta-Fehlberg (RKF) numerical method. The coefficientsof the elements of the Maxwell-Wiechert model were estimated approaching the straining curveof the recovery step of the simulation with the same curve registered on each experimental test.Experimental CCRTs with different unloading times demonstrated that the use of this procedurederived in no influence of the unloading step time in the viscoelastic properties estimation.
PB MDPI
YR 2023
FD 2023-01
LK http://hdl.handle.net/10259/7508
UL http://hdl.handle.net/10259/7508
LA eng
DS Repositorio Institucional de la Universidad de Burgos
RD 29-abr-2024