Thread rolling is restricted to

A. Ferrous materials

B. Ductile materials

C. Hard materials

D. None of these

Answer: Option B

Solution(By Examveda Team)

Materials are limited to ductile materials because the threads are cold formed. .
Also, materials with good deformation characteristics are necessary for rolling; these materials include softer (more ductile) metals and exclude brittle materials, such as cast iron.