Murtumapiste

Murtumapiste, in materials science, refers to the point at which a material develops a crack that propagates until macroscopic failure occurs under applied load. It is commonly described as the fracture point or fracture strength and is typically determined in a mechanical test that drives the material to fracture, such as a tensile or bending test. The key quantity is the stress at fracture, sometimes reported together with the corresponding fracture strain.

Determination of the murtumapiste usually involves loading a specimen until it breaks, recording the stress and strain at fracture. In ductile materials, fracture follows a period of plastic deformation and necking, and the fracture stress may be lower than the material’s ultimate tensile strength. In brittle materials, fracture can occur soon after the elastic region with little or no plastic deformation. The murtumapiste is one aspect of a material’s failure behavior and is distinct from other measures such as yield strength or fracture toughness.

Relation to and distinction from other concepts: the fracture point is not a fixed property independent of conditions; it depends on loading mode, temperature, strain rate, presence of defects or notches, and the environment. Fracture toughness (K_IC) describes resistance to crack propagation and provides complementary information about failure that is not captured by a single fracture stress value.

Significance: knowledge of the murtumapiste informs material selection and structural design, helps assess safety margins, and is standardized in various mechanical testing methods and standards.