Crack propagation was studied in a 2-dimensional decagonal model quasi-crystal. Simulations revealed the predominant role which was played by highly coordinated atomic environments in presenting structure-intrinsic obstacles to both dislocation motion and crack propagation. Under certain overload conditions, these obstacles and the quasi-periodic nature of the crystal resulted in a specific crack propagation mechanism: that is, the crack tip emitted a dislocation; followed by a phason wall along which the material opened up.

Crack Propagation in Quasi-Crystals R.Mikulla, J.Stadler, F.Krul, H.R.Trebin, P.Gumbsch: Physical Review Letters, 1998, 81[15], 3163-6