Draft:Griffith (unit)

• File:Symbol opinion vote.svg Comment: I'm only seeing trivial footnote mentions in the sourcing. The source that is to an online comment is an unreliable source, and the definition and usage sections currently are in need of sourcing. 🌸⁠wasianpower⁠🌸 (talk • contribs) 03:37, 17 December 2025 (UTC)

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This article is about the unit. For the engineer, see Alan Arnold Griffith.

The griffith (symbol: Gf) is a proposed non-SI unit of the quantity expressed in pascal–metre to the one-half (Pa·m^1/2), used in the context of fracture mechanics to quantify material resistance to crack propagation. The unit was suggested as a tribute to the British mechanical engineer Alan Arnold Griffith (1893–1963), whose pioneering work laid the foundations of modern fracture mechanics.

Definition

The griffith is defined as:

$1\text{Gf}=1\text{Pa}\cdot {\text{m}}^{1/2}$

This unit corresponds to the same dimensions as the classical expression of fracture toughness terms used in linear elastic fracture mechanics (LEFM), where stress-intensity factors are commonly expressed in Pa·m^1/2.

Common multiple unit of the griffith is the megagriffith (1 MGf = 10⁶ Gf).

Origin and Proposal

The use of the unit was originally suggested by Pedro Rivero-Antúnez et al.,, and Prof. C. Ramadas and Mr. A. R. Jadhav as a more intuitive and less cumbersome alternative to the expression Pa·m^1/2. Their proposal intended to honour A. A. Griffith’s seminal contributions to the understanding of stress concentration, crack initiation, and brittle fracture.

The first documented proposal of the term griffith in an official international scientific context appears in a 2020 article by Rivero-Antúnez et al... In this work, the authors adopted the designation “griffith” (Gf) for the unit Pa·m^1/2 when reporting fracture-related mechanical properties of alumina-based ceramics. According to the authors, their literature search revealed one earlier public discussion on the website iMechanica, where the possibility of naming the fracture toughness unit had been debated. Since then, it has been used in some other articles published at international journals

Historical Background

The unit is named after Alan Arnold Griffith, who introduced the energy-based approach to fracture and established the relationship between crack size, applied stress, and failure in brittle solids. His classical 1921 paper, The Phenomena of Rupture and Flow in Solids, is recognized as one of the foundational works of modern fracture mechanics..

Usage

Although the griffith is not an SI unit and is not formally recognized by standards organizations, it has been proposed as a convenient shorthand within the fracture mechanics community, particularly in scientific publications dealing with the mechanical characterization of brittle materials.

See also

• Fracture mechanics
• Fracture toughness
• Stress intensity factor
• Alan Arnold Griffith
• Linear elastic fracture mechanics