What does the Tsai–Wu failure criterion describe?

What does the Tsai–Wu failure criterion describe?

• A. A simple maximum stress criterion for isotropic materials
• B. A general criterion for anisotropic materials using a polynomial yield/failure function with interaction terms to predict failure in any load direction
• C. A criterion that only applies to composite laminates under pure tension
• D. A criterion for ductile metals under high-temperature creep

Answer: (B)

The Tsai–Wu description is a general failure criterion for anisotropic materials, especially composites, formulated as a second‑order polynomial in the stress components that includes interaction terms. This lets it predict failure under any loading direction because it accounts for how normal and shear stresses interact in different material directions. The coefficients reflect strengths in tension and compression along the principal directions, and the cross terms (like σ1σ2, σ1σ3, σ2σ3) capture the combined effect of multiple stresses. It’s not limited to a simple maximum-stress rule, nor restricted to pure tension, isotropic materials, or creep in metals.

The Tsai–Wu description is a general failure criterion for anisotropic materials, especially composites, formulated as a second‑order polynomial in the stress components that includes interaction terms. This lets it predict failure under any loading direction because it accounts for how normal and shear stresses interact in different material directions. The coefficients reflect strengths in tension and compression along the principal directions, and the cross terms (like σ1σ2, σ1σ3, σ2σ3) capture the combined effect of multiple stresses. It’s not limited to a simple maximum-stress rule, nor restricted to pure tension, isotropic materials, or creep in metals.