抄録
The crack growth stability condition of brittle materials was considered using an equilibrium Gibbs free energy diagram, where the universal relationship of the dimensionless load and dimensionless displacement was utilized to calculate the Gibbs free energy of elastic fracture systems. The free energy diagram was then applied to a crack stabilizer which is specially designed for measuring the R-curve behavior of brittle ceramics showing unstable fracture. Some experimental R-curves of polycrystalline ceramics were measured by the use of the stabilizer.
