Skip to main content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Dynamic Compression Tests of Alumina Dumbbells Using a Spherical Joint

Published

Author(s)

Richard Rhorer, George D. Quinn, Steven P. Mates

Abstract

The dynamic compressive strength of ceramic armor materials is difficult to obtain experimentally due to the sensitivity of fracture strength to even small bending stresses. In this work we introduce a spherical joint into a compression Kolsky bar to investigate whether the joint can alleviate bending stresses in compression tests on alumina dumbbell specimens. Tests are conducted both with and without the spherical joint, and high-speed (75,000 frames/s) 3D DIC is used to measure both the strain field on the dumbbell specimen and motion, if any, in the spherical joint. Results indicate that the spherical joint is extremely sensitive to eccentric loading and in most cases increases rather than decreases the bending stresses in the test, leading to lower apparent fracture strengths.
Proceedings Title
Proceeding of the Society for Experimental Mechanics 2019 Annual Meeting
Conference Dates
June 3-6, 2019
Conference Location
Reno, NV

Keywords

Kolsky Bar, Dynamic Fracture Strength, Dumbbell Specimens, 3D DIC, High-Speed Video
Created December 19, 2019, Updated February 6, 2020