TY - JOUR
T1 - Nano-indentation response of ultrahighmolecular weight polyethylene (UHMWPE)
T2 - A detailed analysis
AU - Iqbal, Tanveer
AU - Camargo, S. S.
AU - Yasin, Saima
AU - Farooq, Ujala
AU - Shakeel, Ahmad
PY - 2020/4/1
Y1 - 2020/4/1
N2 - Nano-indentation, a depth sensing technique, is a useful and exciting tool to investigate the surface mechanical properties of a wide range of materials, particularly polymers. Knowledge of the influence of experimental conditions employed during nano-indentation on the resultant nano-mechanical response is very important for the successful design of engineering components with appropriate surface properties. In this work, nano-indentation experiments were carried out by selecting various values of frequency, amplitude, contact depth, strain rate, holding time, and peak load. The results showed a significant effect of amplitude, frequency, and strain rate on the hardness and modulus of the considered polymer, ultrahigh molecular weight polyethylene (UHMWPE). Load-displacement curves showed a shift towards the lower indentation depths along with an increase in peak load by increasing the indentation amplitude or strain rate. The results also revealed the strong dependence of hardness and modulus on the holding time. The experimental data of creep depth as a function of holding time was successfully fitted with a logarithmic creep model (R2 ≥ 0.98). In order to remove the creeping effect and the nose problem, recommended holding times were proposed for the investigated polymer as a function of different applied loads.
AB - Nano-indentation, a depth sensing technique, is a useful and exciting tool to investigate the surface mechanical properties of a wide range of materials, particularly polymers. Knowledge of the influence of experimental conditions employed during nano-indentation on the resultant nano-mechanical response is very important for the successful design of engineering components with appropriate surface properties. In this work, nano-indentation experiments were carried out by selecting various values of frequency, amplitude, contact depth, strain rate, holding time, and peak load. The results showed a significant effect of amplitude, frequency, and strain rate on the hardness and modulus of the considered polymer, ultrahigh molecular weight polyethylene (UHMWPE). Load-displacement curves showed a shift towards the lower indentation depths along with an increase in peak load by increasing the indentation amplitude or strain rate. The results also revealed the strong dependence of hardness and modulus on the holding time. The experimental data of creep depth as a function of holding time was successfully fitted with a logarithmic creep model (R2 ≥ 0.98). In order to remove the creeping effect and the nose problem, recommended holding times were proposed for the investigated polymer as a function of different applied loads.
KW - Creep
KW - Hardness
KW - Modulus
KW - Nano-indentation
KW - Ultrahigh molecular weight polyethylene
UR - http://www.scopus.com/inward/record.url?scp=85086634835&partnerID=8YFLogxK
U2 - 10.3390/POLYM12040795
DO - 10.3390/POLYM12040795
M3 - Article
AN - SCOPUS:85086634835
SN - 2073-4360
VL - 12
JO - Polymers
JF - Polymers
IS - 4
M1 - 795
ER -