During what kind of testing is a material's toughness evaluated?

Toughness is a critical material property that defines its ability to absorb energy and plastically deform without fracturing. Impact testing is specifically designed to measure this property by subjecting a material to sudden and extreme forces. In this type of testing, a sample is typically struck with a hammer or other weight at high velocity to assess how much energy the material can absorb before it fails. The results are indicative of the material's resistance to cracks and its performance under sudden loading conditions.

The emphasis on sudden force in impact testing allows for a clear evaluation of toughness, as it simulates real-world scenarios where materials may experience unexpected shocks. This characteristic makes impact testing distinctly suitable for assessing toughness compared to other testing methods that might focus on different material behaviors, such as stress, fatigue, or temperature-related properties.