Question

Decrease in stress at constant deformation under creep conditions is termed as the

• A. Stress relaxation
• B. Residual stress
• C. Stress relief
• D. Proof stress

Hint:

Remember: \textbf{Stress relaxation} = stress decreases at constant strain; \textbf{Creep} = strain increases at constant stress.

Answer 1

The Correct Option is A

Step 1: Understanding the condition Under creep conditions, materials are subjected to constant deformation (strain) over time at elevated temperatures. The internal resistance to this deformation—stress—gradually decreases. Step 2: Defining stress relaxation \textit{Stress relaxation} refers to the phenomenon where the internal stress in a material reduces over time when it is held at a constant strain. This typically happens in viscoelastic and creep-sensitive materials like metals at high temperature or polymers. Conclusion: Among the given choices, the correct term that describes this stress reduction behavior at constant deformation is Stress relaxation.