Which of the following is NOT a factor influencing thermal shock resistance?

• A. High fracture strengths
• B. High thermal conductivities
• C. Low coefficients of thermal expansion
• D. High modulus of elasticity

Answer: (D)

Thermal shock resistance measures how well a material can survive rapid temperature changes without cracking. The factors that help it are: high fracture strength or toughness so cracks don’t initiate or propagate easily, high thermal conductivity to minimize temperature gradients inside the material, and a small coefficient of thermal expansion so the material doesn’t change size much with temperature. The modulus of elasticity, which describes stiffness, isn’t a direct lever for resisting thermal cracking in the same way. While stiffness affects how stresses develop under temperature changes, it doesn’t inherently improve the ability to withstand rapid thermal shocks the way toughness, heat transfer, and expansion behavior do. So high modulus of elasticity is not a factor that enhances thermal shock resistance, making it the best choice among the options.