Failure physics is a research field dedicated to understanding the fundamental physical mechanisms driving the degradation and failure of materials, components, and systems. It applies principles from various branches of physics to analyze how physical processes initiate, propagate, and culminate in functional failure. This domain investigates underlying physical phenomena such as mechanical stresses, thermal loads, radiation effects, and chemical interactions, and their complex interplay, which lead to damage accumulation and eventual breakdown. Characterized by a focus on mechanistic understanding and quantitative predictive modeling, failure physics provides essential insights for enhancing the reliability, safety, and operational lifespan of critical engineered systems, including those in demanding environments like nuclear facilities.