Question

For the detection of discontinuities beneath the surface, liquid penetrant testing method can be used.

(a) True

(b) False

The question was asked by my school principal while I was bunking the class.

The above asked question is from Inspection Procedures in division Inspection Testing in Foundries of Casting-Forming-Welding I

Answer 1

The correct answer is:

(b) False

Explanation:

Liquid penetrant testing (LPT) is used primarily to detect surface-breaking discontinuities or defects, such as cracks or porosity, that are open to the surface of a material. The process involves applying a liquid penetrant to the surface of the material, allowing it to seep into any surface-breaking defects, and then cleaning the surface and applying a developer to reveal the defects.

However, LPT is not effective for detecting discontinuities beneath the surface. For subsurface defects, other non-destructive testing (NDT) methods such as ultrasonic testing (UT) or x-ray testing would be more appropriate.

So, the statement is false because liquid penetrant testing can only detect surface-breaking defects, not those beneath the surface.