Question

Vickers microhardness (HV) of a ductile material A is higher than another ductile material B. Which of the following is/are true?

• A. Young’s modulus of A is greater than B
• B. Yield strength of A is greater than B
• C. Scratch resistance of A is greater than B
• D. Ductility of A is greater than B

Hint:

Hardness is strongly linked to yield strength and scratch resistance, but not necessarily to Young's modulus or ductility.

Answer 1

The Correct Option is B, C

Vickers hardness (HV) is a measure of a material’s resistance to permanent deformation. Higher hardness generally correlates with higher yield strength because a harder material resists plastic deformation more effectively. Therefore, if material A has a higher HV than material B, the yield strength of A is expected to be greater, making option (B) true.
Hardness is also directly related to scratch resistance: a harder material is more difficult to scratch. Since A has higher HV, it must also have higher scratch resistance than B, so (C) is true.
Young’s modulus is not directly related to hardness; materials with different hardness values can have similar elastic moduli. Thus, (A) is false.
Higher hardness usually means lower ductility because a hard material undergoes less plastic deformation. Hence, (D) is also false.