PAPERS & REPORTS

Introduce technical papers and reports of IIT (Instrumented Indentation Technology) and correlated fields.

 

Title

Characterization of elastic modulus and work of adhesion in elastomeric polymers using microinstrumented indentation technique

Author

Gyujei Lee∗, Seung-Kyun Kang, Dongil Kwon

Department of Materials Science and Engineering, Seoul National University, Seoul 151-742, Republic of Korea

Press and Date of publication

Article history:

Received 3 April 2008

Received in revised form 2 June 2008

Accepted 4 June 2008

Abstract

This study combines Johnson–Kendall–Roberts (JKR) theory with the instrumented indentation technique

(IIT) to evaluate thework of adhesion and modulus of elastomeric polymers. Indentation testingwas used

to obtain load–displacement data for contact between a tungsten carbide indenter and the elastomeric

polymer. The JKR contact model, which was designed to take polymer viscoelastic effects into account,

was applied to adjust the contact area and the elastic modulus, which the Hertzian contact model would

respectively underestimate and overestimate. In addition,we obtained the thermodynamicwork of adhesion

by considering the surface energy in this contact model. In order to define the relation between the

JKR contact radius and applied load without measuring the contact radius optically, we used a relation

between applied load and contact stiffness by examining the correlation between the JKR contact radius

and stiffness through dimensional analysis with 14 elastomeric polymers. This work demonstrated that

the interfacialwork of adhesion and elastic modulus of a compliant polymer can be obtained fromsimple

instrumented indentation testing without area measurement, and provided an algorithm for compliant

polymer characterization.

ⓒ 2008 Elsevier B.V. All rights reserved.

Keywords:

Instrumented indentation technique (IIT)

Johnson–Kendall–Roberts (JKR) theory

Elastomeric polymer

Thermodynamic work of adhesion

Dimensional analysis