ET ASNT Level II Practice Exam 2025 – Your All-In-One Guide to Achieve Exam Success!

The term used to describe the induction field B within a material when the H field strength returns to zero is referred to as residual magnetism. This phenomenon occurs because certain materials can retain magnetic field characteristics even after the external magnetic influence has been removed. Essentially, when the magnetizing force (H) is decreased to zero, the material does not completely demagnetize; instead, it retains a certain level of magnetism, which is measured as the induction (B) within the material.

Understanding this concept is critical in applications involving ferromagnetic materials, such as in transformers and magnetic storage devices. Residual magnetism is an important factor to consider, as it affects the overall magnetic properties and behavior of the material in practical applications.