Explain why metals exhibit higher ductility under hydrostati

Explain why metals exhibit higher ductility under hydrostatic pressures.

Solution

Improved Ductility here is taken as measure of a metal to withstand higher tensile stress compared to their normal behaviour. The fracture in metals is predicted as consequence of creation of new tiny voids, amalgamation of these voids to form a flaw, then flaw /crack propagation leading to final rupture. Application of sufficiently large hydrostatic pressure (more than 600-1000 MPa) is a means to side-step creation of new voids, reduce their amplification and delay the merger of such flaws. Thus the metals under very high hydrostatic pressures, the normal phenomena of void formation is hindered leading to improved ductility.