Question

What is the fracture toughness of aluminum alloy?

(a) 2 J m^-2

(b) 3 J m^-2

(c) 4 J m^-2

(d) 6 J m^-2

I had been asked this question in an interview for internship.

My doubt is from Fracture Toughness, Protection against Fracture in division Imperfection in Metal Crystals, Fracture, Corrosion and Oxidation of Engineering Material & Metallurgy

Answer 1

The correct choice is (b) 3 J m^-2

Explanation: Although aluminum has a range of 20-100 J m^-2, the true surface energy lays at less than 2 J m-2. This value for polystyrene is about 2 J m^-2 even though it is relatively brittle.