Stress and Strain....fracture and flow If a material has a maximum tensile fracture stress of S, and a maximum shear stress of T which causes plastic flow, how will it deform: If T=S and if 3T=S ?? Its not an important question, but Im just curious? I cant get my head around it. Can the material both fracture and flow in the first case? And will it flow in the 2nd, since applying S, you have already passed T? Im not certain if there are mathematics to work this out, or if conceptual answers would be fine. Cheers guys!!