Tensile elongation at break for polymers related to Vickers hardness

doi:10.1016/j.matlet.2020.128179

Materials Letters

Volume 276, 1 October 2020, 128179

https://doi.org/10.1016/j.matlet.2020.128179 Get rights and content

Highlights

•
We have demonstrated the existence of a relationship between tensile elongation at break and Vickers hardness of polymers.
•
The relationship is represented by an equation.
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Experimental determination of one of these quantities makes possible calculation of the other.

Abstract

Polymeric materials and components need, first of all, to ‘survive attacks’ by external mechanical forces. One can apply a force slowly along the main axis of the specimen—such as in tensile testing. One can apply a force rapidly perpendicularly to the surface—such as in Vickers hardness determination. We provide for polymers an equation relating their tensile elongation at break to the Vickers hardness.

Section snippets

Introduction and scope

As argued in the textbook of Brostow and Hagg Lobland [1], mechanical, tribological, thermophysical, rheological and other properties of materials are determined by structures and interactions at the molecular and atomic level. Therefore, we believe that quantitative relationships between macroscopic properties should exist. Some of these properties are well defined, such as those obtainable from tensile testing. Some other properties—even used for a long time—were discussed by hand-waving

Relating Vickers hardness to tensile elongation at break

We have hypothesized that a relationship between the two quantities named in the title of this section exists. Temperature = 20 °C was chosen since more reliable data are available for that temperature than for higher or lower temperatures. Moreover, the international group noted above [6] reported that the temperature changes from 24 °C to 45 °C do not lead to considerable variations of the sensor output. Polyethylenes are at 20 °C above their glass transitions, so is polypropylene [11], while

Concluding remarks

In earlier work we have dealt with effects of changes of the surface roughness of LDPE on scratch resistance and wear [32]. Vickers hardness is classified as a mechanical property—but it is also a surface property.

Vickers hardness is pertinent for a variety of materials. Ben Mahmoud and Amlouk [33] use it in their abacus for optimizing semiconductor thin film materials. Nisha Santha Kumari and coworkers [34] studied it for cadmium mercury thiocyanate (CMTC) single crystals.

As discussed in some

CRediT authorship contribution statement

Witold Brostow: Supervision, Writing - original draft, and writing - review and editing. Danny Zhang: Investigation, Validation.

Declaration of Competing Interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Acknowledgements

We would like to thank a reviewer for comments which directed us towards providing more perspicuity to this publication. One of us (D.Z.) is a student in the Texas Academy of Mathematics and Science (TAMS), Denton.

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View full text

Tensile elongation at break for polymers related to Vickers hardness

Highlights

Abstract

Section snippets

Introduction and scope

Relating Vickers hardness to tensile elongation at break

Concluding remarks

CRediT authorship contribution statement

Declaration of Competing Interest

Acknowledgements

Mater. Letters X

Dental Mater.

Wear

Polymer

Polymer

Wear

Compos. Sci. Tech.

Tribol. Int.

Mater. Letters

Mater. Letters

Materials: Introduction and Applications

Sliding wear, viscoelasticity and brittleness of polymers

J. Mater. Res.

Power loss characteristics of a sensing element based on a polymer optical fiber under cyclic tensile elongation

Sensors

Strain sensor based on a flexible polyimide ionogel for application in high- and low-temperature environments

J. Mater. Chem. C

Dynamic mechanical characterization with respect to temperature, humidity, frequency and strain in mPOFs made of different materials

Optical Mater. Express

Dynamic mechanical analysis on a polymethyl methacrylate (PMMA) polymer optical fiber

IEEE Sensors J.

Flexibility of polymers defined and related to dynamic friction

J. Mater. Sci. Res.