Britle materials have abilty of a material to plasticall strain without fracture

no.

Explanation:

brittle material are the material which cannot sustain huge load the fracture before reaching to the plastic limit.

brittle material have high carbon content present in them the do not yielding point so the break suddenly.

cast iron, glass etc are the perfect example of the brittle material and they do not  show plastic strain.

that is why they do not posses plastic strain.