Question

__________ is a binder that resists molten metal.

(a) Coal tar

(b) Core oil

(c) Pitch

(d) Chamotte

I got this question in an international level competition.

My doubt stems from Types of Binders in the Moulding Sand, Types of Base Sand topic in portion Casting Processes of Foundry and Forging

Answer 1

Correct answer is (c) Pitch

For explanation I would say: Pitch is a coal tar product. In the form of ground powder, the pitch may be added to up to 3% or more. With the presence of the molten metal around the core, pitch develops the hot strength to resist the molten metal.