The ductile and brittle fractures occur mainly due to 1) dislocation propagation, respectively 2) crack movement, respectively 3) sliding of grain boundaries 4) stress concentration and dislocation...

Extracted text: The ductile and brittle fractures occur mainly due to 1) dislocation propagation, respectively 2) crack movement, respectively 3) sliding of grain boundaries 4) stress concentration and dislocation climb, respectively movement and crack propagation and dislocation