Dian LiFollow

Publication Date

2021

Document Type

Dissertation/Thesis

First Advisor

Gau, Jenn-Terng

Degree Name

M.S. (Master of Science)

Legacy Department

Department of Mechanical Engineering

Abstract

A Split-Hopkinson apparatus is a device used to dynamically test material properties for constructing constitutive model and can be used for high strain rate deformation research and experiments. NIU currently has a Split-Hopkinson apparatus that can conduct compressive tests only. The goal of this thesis is to redesign and rebuild the existing apparatus, so the high strain rate tensile tests can be conducted.

Multi-improvements were applied to the Split Hopkinson apparatus in order to improve its working performance. For conducting high strain rate tensile test, the Split-Hopkinson system has been rebuilt with a load-inversion device. The load-inversion device was designed for converting compressive loading pulse to tensile pulse such that an output bar connected to the device can apply the tensile loading pulse to the specimen. The rebuilt system has been used to conduct high strain rate tensile test on stainless steel 304 foils with thickness of 100µm. The signals from the two strain gauges on the output bars can be used to calculate the flow stress curves of the specimens. A high-speed camera was also used to take pictures of the deformation history of the specimen that can be used to obtain the relation of strain and time for computing strains and strain rates.

Extent

56 pages

Language

eng

Publisher

Northern Illinois University

Rights Statement

In Copyright

Rights Statement 2

NIU theses are protected by copyright. They may be viewed from Huskie Commons for any purpose, but reproduction or distribution in any format is prohibited without the written permission of the authors.

Media Type

Text

Download

Share

COinS