Definition - What does Brittleness mean?
This is a mechanical property of a material manifested by failure without undergoing any deformation on application of stress. Materials with this property have elastic proportionality in stress and strain. Most of the materials that have brittleness are normally ceramics, glass and cold metals. Brittleness in metals helps in determining the critical cooling temperature that transforms a ductile material into a brittle material. Therefore, it is a crucial topic in the marine industry.
Corrosionpedia explains Brittleness
When metals and polymers are cooled below a critical temperature—ductile to brittle transition temperature (DBTT) or glass transition temperature (Tg) respectively—they become brittle. This rapid change is catastrophic, especially when forces are acting on the body. The crack propagation is noted to be perpendicular to the applied forces that occur through molecular grains or grain boundaries.
Temperature in this case controls the molecular structure of a material such that it fails to retain its elasticity, hence leads to material failure. Basically, all materials will eventually fail when the limits are exceeded, but in the case that it fails before any change in shape and geometrical size, then the material falls under brittleness.
Brittleness material failure occurs when there are two conditions:
- Stress acting on the surface of the material
- Surrounding temperatures below the melting point of a material
The Effects of Stress Concentration on Crack Propagation