G1c (critical strain energy release rate)

G1c, or the critical strain energy release rate, is a measure used in materials science to quantify the energy required to propagate a crack in a material under tension. It represents the threshold beyond which a crack will grow, leading to failure. Essentially, it indicates how much energy must be absorbed by the material to expand an existing crack. Higher values of G1c imply that a material can withstand greater stress before cracks spread, making it more durable. Understanding G1c helps engineers design safer structures and choose materials that can resist fracturing under load.