Question

Core oil and binders change their chemical properties at what temperature?

(a) 200°F – 300°F

(b) 300°F – 400°F

(c) 400°F – 500°F

(d) 500°F – 600°F

The question was posed to me during an internship interview.

Enquiry is from Baking the Cores topic in chapter Core and Core Making of Casting-Forming-Welding I

Answer 1

Right option is (c) 400°F – 500°F

To explain I would say: Whenever any material is heated to a temperature high for its properties, there is a change in its chemical and physical aspects seen. Core oils and organic binders used in backing the core, change their physical properties at 400°F – 500°F.