Gigapascal

Gigapascal (symbol GPa) is an SI-derived unit of pressure equal to one billion pascals. The pascal is defined as one newton per square meter, so 1 GPa = 1 × 10^9 Pa. In common practice, 1 GPa also equals 1000 MPa or 1,000,000 kPa. In imperial units, 1 GPa is approximately 145,038 psi. The gigapascal is used for pressures and stresses that are large compared with everyday atmospheric pressure.

Giga pascals appear in science and engineering contexts where high pressures or large stresses are involved. They are used to describe material properties such as yield strength, ultimate tensile strength, and elastic moduli, as well as pressures generated in high-pressure physics experiments and deep-Earth geophysics. Everyday structural engineering typically deals with stresses expressed in MPa, while GPa-scale values are common for high-strength materials or extreme conditions.

In materials science, many metals have yield strengths ranging from tens to hundreds of MPa, with high-strength alloys commonly approaching or surpassing 1 GPa. The elastic moduli (Young’s modulus) of metals and ceramics are often tens to hundreds of GPa. In laboratories, diamond anvil cells can generate pressures on the order of hundreds of gigapascals. Geoscientists describe interior planetary pressures in the gigapascal range, with the deepest regions reaching several hundred gigapascals.