Accession Number:

ADA277744

Title:

Modeling the Impact Behavior of High Strength Ceramics

Descriptive Note:

Final rept.

Corporate Author:

ARMY RESEARCH LAB WATERTOWN MA MATERIALS DIRECTORATE

Personal Author(s):

Report Date:

1993-12-01

Pagination or Media Count:

42.0

Abstract:

An advanced constitutive model is used to describe the shock and high strain rate behaviors of silicon carbide SC, boron carbide B4C, and titanium diboride TiB2 under impact loading conditions. The models governing equations utilize a set of microphysically-based constitutive relationships to model the deformation and damage processes in a ceramic. The total strain is decomposed into elastic, plastic, and microcracking components. The plastic strain component was calculated using conventional viscoplastic equations. The strain components due to microcracking utilized relationships derived for a penny- shaped crack containing elastic solids. The main features of the model include degradation of strength and stiffness under both compressive and tensile loading conditions. When loaded above the Hugoniot elastic limit HEL, the strength is limited by the strain rate dependent strength equation. However, below the HEL, the strength variation with respect to strain rate and pressure is modeled through microcracking relationships assuming no plastic flow. The ceramic model parameters were determined using a set of VISAR data from the plate impact experiments. Impact, Ceramics, Modeling, Plate impact, High strain rate, Cracks.

Subject Categories:

  • Ceramics, Refractories and Glass

Distribution Statement:

APPROVED FOR PUBLIC RELEASE