Question

Shrinkage cavities cannot be reduced by application of pressure; it can only be avoided by having a tight seal in the casting system.

(a) True

(b) False

I have been asked this question in exam.

My question comes from Squeeze Casting in portion Special Casting Techniques of Casting-Forming-Welding I

Answer 1

The correct answer is:

(b) False

Explanation: Shrinkage cavities in casting are typically caused by the solidification of metal, where the volume decreases as the metal cools, leading to voids or cavities. These shrinkage cavities can indeed be reduced or avoided by the application of pressure, which is the principle behind squeeze casting. In squeeze casting, pressure is applied during solidification, helping to force the metal into the mold and reduce or eliminate shrinkage cavities by ensuring the molten metal fills all voids and maintains density during the cooling process. Therefore, the statement that shrinkage cavities cannot be reduced by application of pressure is false.