TY - JOUR
T1 - Size effect in microcompression of polystyrene micropillars
AU - Guruprasad, Thimmappa Shetty
AU - Bhattacharya, Shantanu
AU - Basu, Sumit
N1 - Publisher Copyright:
© 2016 Elsevier Ltd All rights reserved.
PY - 2016/8/19
Y1 - 2016/8/19
N2 - Experiments by He et al. [J.Y. He, Z.L. Zhang, M. Midttun, G. Fonnum, G.I. Modahl, H. Kristiansen, and K. Redford. Size effect on mechanical properties of micron-sized PS-DVB polymer particles. Polymer 2008, 49(18), 3993] have indicated that polymers exhibit enhancement of strength at length scales of the order of microns. This is surprising since size effects, widely reported for FCC metals, owe their origin to the presence of crystalline defects, particularly dislocations. On the other hand, polymers being a material of choice in microfabrication, these results assume technological importance. In this work, we conduct controlled experiments on polystyrene (PS) micropillars to ascertain whether they exhibit size effects. The pillars are microfabricated and hence free of beam damage. The experimental load displacement curves obtained from microcompression experiments are matched with computer simulations on similar samples using a well-calibrated constitutive model. Our results demonstrate significant intrinsic size effect on the yield strength, though effects of size on rehardening response turned out to be an experimental artifact.
AB - Experiments by He et al. [J.Y. He, Z.L. Zhang, M. Midttun, G. Fonnum, G.I. Modahl, H. Kristiansen, and K. Redford. Size effect on mechanical properties of micron-sized PS-DVB polymer particles. Polymer 2008, 49(18), 3993] have indicated that polymers exhibit enhancement of strength at length scales of the order of microns. This is surprising since size effects, widely reported for FCC metals, owe their origin to the presence of crystalline defects, particularly dislocations. On the other hand, polymers being a material of choice in microfabrication, these results assume technological importance. In this work, we conduct controlled experiments on polystyrene (PS) micropillars to ascertain whether they exhibit size effects. The pillars are microfabricated and hence free of beam damage. The experimental load displacement curves obtained from microcompression experiments are matched with computer simulations on similar samples using a well-calibrated constitutive model. Our results demonstrate significant intrinsic size effect on the yield strength, though effects of size on rehardening response turned out to be an experimental artifact.
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U2 - 10.1016/j.polymer.2016.06.010
DO - 10.1016/j.polymer.2016.06.010
M3 - Article
AN - SCOPUS:84975217391
SN - 0032-3861
VL - 98
SP - 118
EP - 128
JO - Polymer
JF - Polymer
ER -