Charakterisierung von Elastomeren mittels dynamischer Indentation und vergleichender Methoden
type: CreativeWork
description: This work deals with a new developed method of dynamic-machanical characterization of elastomeric surfaces. Hereby a conical indenter penetrates the surface of elastomers. The indentation depths are in the order of about 20 – 100 mm. Quasistatic indentations and hysteresis-curves as well as sinusoidal indentations in the micro-range are possible to be performed because of the use of a piezo-actuator. Therefore the stiffness can be devided in an elastic and a viscose term. Defined scanning of the surface in x- and y-direction enables one to estimate the homogeneity of the material by the help of the average value and the standard deviation of the stiffness values and mechanical imaging of the same as well. The obtained mechanical images have the length of a few millimeters with local resolution of a few micrometers. It could be shown, that the theories according to the literature are not able to describe the indentation curves. A reason might be, that adhesion and friction between indentation probe and sample as well as the special material properties of elastomers were not regarded (by derivating the theory). By the help of different compound formulations (variation of the microstructure of the polymers, crosslink-density, filler content and type of filler) vulcanizates with different mechanical properties were investigated. Linear correlations between stiffness values and conventional values obtained on macroscopic samples were obtained (stress strain curves, dynamic-mechanical analysis). There are some hints indicating that an interaction between tip and surface has to be regarded. For elastomers typical properties, e.g. the “Payne effect”, the “frequency-temperature equivalence principle” according to Williams, Landel and Ferry and the “structure-concentration equivalence principle” according to Kraus was obtained. Investigations in the region of the glass transition temperature of an elastomer revealed, that Tg indicates the limit for sinusoidal indentation, bec…
abstract: This work deals with a new developed method of dynamic-machanical characterization of elastomeric surfaces. Hereby a conical indenter penetrates the surface of elastomers. The indentation depths are in the order of about 20 – 100 mm. Quasistatic indentations and hysteresis-curves as well as sinusoidal indentations in the micro-range are possible to be performed because of the use of a piezo-actuator. Therefore the stiffness can be devided in an elastic and a viscose term. Defined scanning of the surface in x- and y-direction enables one to estimate the homogeneity of the material by the help of the average value and the standard deviation of the stiffness values and mechanical imaging of the same as well. The obtained mechanical images have the length of a few millimeters with local resolution of a few micrometers. It could be shown, that the theories according to the literature are not able to describe the indentation curves. A reason might be, that adhesion and friction between indentation probe and sample as well as the special material properties of elastomers were not regarded (by derivating the theory). By the help of different compound formulations (variation of the microstructure of the polymers, crosslink-density, filler content and type of filler) vulcanizates with different mechanical properties were investigated. Linear correlations between stiffness values and conventional values obtained on macroscopic samples were obtained (stress strain curves, dynamic-mechanical analysis). There are some hints indicating that an interaction between tip and surface has to be regarded. For elastomers typical properties, e.g. the “Payne effect”, the “frequency-temperature equivalence principle” according to Williams, Landel and Ferry and the “structure-concentration equivalence principle” according to Kraus was obtained. Investigations in the region of the glass transition temperature of an elastomer revealed, that Tg indicates the limit for sinusoidal indentation, bec…
author: Herrmann, Volker
language: ger
keywords: info:eu-repo/classification/ddc/540, Chemie
date published: 2002
date modified: 2026-07-30T19:42:01Z
provider: RWTH Aachen University
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: Publikationsserver der RWTH Aachen University