Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Rheology of ballistic clay: the effect of temperature and shear history



Ran Tao, Kirk D. Rice, Aaron M. Forster


Ballistic clay is used as a backing material for standards-based ballistic resistance tests for the purposes of providing a measure of the energy transferred to the body when a threat is defeated. However, this material exhibits complex thermomechanical behavior under actual usage conditions. In this work, we characterize rheological properties of the standard backing clay material, Roma Plastilina No. 1, used for body armor testing, using a rubber process analyzer. Test methods employed include oscillatory strain sweep, frequency sweep, and oscillatory strain ramp. The results show that the material is highly nonlinear, thermorheologically complex, and thixotropic. The modulus decreases under dynamic deformation and partially recovers when the deformation is discontinued. Experimental protocols developed in this study can be applied for the characterization of other synthetic clay systems.
Proceedings Title
SPE ANTEC® Anaheim 2017
Conference Dates
May 8-10, 2017
Conference Location
Anaheim, CA, US
Conference Title
Society of Plastics Engineers Annual Technical Conference


rheology, rubber process analyzer, ballistic witness materials, thixotropy


Tao, R. , Rice, K. and Forster, A. (2017), Rheology of ballistic clay: the effect of temperature and shear history, SPE ANTEC® Anaheim 2017, Anaheim, CA, US, [online], (Accessed July 18, 2024)


If you have any questions about this publication or are having problems accessing it, please contact

Created May 9, 2017, Updated April 12, 2022