What is the difference between a fire crack and a tension crack?

A tension crack is characterized by the failure of a material under tensile stress, typically seen in the context of structural components. These cracks often occur in metal structures where stress concentrations exist, such as between rivets. When a tension crack forms, it can propagate through the component, leading to structural failure, which is why it is considered very dangerous.

In contrast, a fire crack arises from thermal stress that results from high temperatures, usually related to fire exposure. Fire cracks do not necessarily follow consistent paths like tension cracks do, and they are not specifically linked to a structural configuration, such as rivet placements. While fire cracks may also compromise structural integrity, they often appear more randomly and may not present the immediate danger associated with the linear propagation of tension cracks.

Understanding these distinctions is crucial in engineering for assessing the risks and implications of structural failures under different conditions. Tension cracks specifically point to the danger posed by stress in structural members, while fire cracks indicate damage due to thermal effects.