Which property describes a material's resistance to scratching, abrasion or indentation?

• A. Ductility
• B. Malleability
• C. Tensile Strength
• D. Hardness

Answer: (D)

Hardness is about how well a material resists surface deformation from a scratching or indenting action. It measures how difficult it is to leave a scratch or an impression on the surface when a sharp or pointed tool is applied, often using tests that push an indenter into the material or scratch its surface. This property is commonly quantified with scales like Mohs for scratch resistance or Vickers/Rockwell/Brinell for indentation hardness. It’s different from ductility, which is how much a material can stretch or deform under tension; malleability, which is how well it can be hammered into sheets; and tensile strength, which is the maximum stress it can withstand before breaking. So the feature describing resistance to scratching, abrasion, or indentation is hardness.