# Dynamic Compressive Behavior, Constitutive Modeling, and Complete Failure Criterion of 30 Vol.% B4C/2024Al Composite

## TL;DR

This study examines how a boron carbide and aluminum composite behaves under pressure and proposes a new model to predict its failure.

## Contribution

A modified Johnson–Cook model and complete failure criterion were proposed and validated for dynamic compressive behavior of B4C/2024Al composites.

## Key findings

- Strain softening was a key feature in the stress–strain curve of the composite.
- Taylor and load transfer mechanisms accounted for 89.6% of the yield strength enhancement.
- The modified JC model accurately described plastic deformation with less than 15% mean absolute error under dynamic loading.

## Abstract

This study investigated the compressive behavior of 30 vol.% boron carbide (B4C)/2024 aluminum (Al) composites under quasi-static and dynamic loading at different temperatures. Building on the experimental findings, the Johnson–Cook (JC) model was modified, and a complete failure criterion was proposed. These were validated in Abaqus employing the user subroutine for hardening (VUHARD), which incorporated both the modified JC (MJC) model and the complete failure criterion. Experimental results revealed that strain softening was an important feature of the stress–strain curve. The analysis of mechanisms contributing to yield strength revealed that Taylor and load transfer mechanisms dominated, accounting for 89.6% of the total enhancement. Microstructural analysis identified particle fracture and matrix damage were the primary mechanisms driving material failure. Microcracks mainly propagated through the matrix and interface or directly through the ceramic particles and the matrix. The MJC model demonstrated high accuracy in describing the plastic deformation behavior of the composite, with a mean absolute error (MAE) below 15% under dynamic loading. Further simulation confirmed that finite element analyses using the VUHARD subroutine accurately captured the plastic deformation and crack propagation behaviors of the composite under dynamic loading. This study offers a novel approach to describe the plastic deformation and failure behaviors of ceramic-reinforced aluminum matrix composites under dynamic loading conditions.