Question

Sodium bentonite and Calcium bentonite has the same binding properties.

(a) True

(b) False

I have been asked this question by my college director while I was bunking the class.

I want to ask this question from Moulding Sand Binders and Additives topic in portion Pattern Materials & Moulding Sand Tests of Foundry and Forging

Answer 1

Right option is (b) False

For explanation: Sodium and Calcium bentonite has contras properties. Sodium Bentonite provides better swelling properties volume increases some 10 to 20 times, high dry strength which lowers the risk of erosion whereas the Calcium Bentonite has the low dry strength but higher green strength.