Thickness dependence of the indentation hardness of glass plates

Abstract

The load required to produce fracture m glass plates by pressing steel balls onto both upper and lower surfaces of the plate has been recorded experimentally as a function of the thickness of the plate and the diameter of the Indenter. It is observed that for a sufficiently large indenter the fracture load decreases rapidly as the thickness of the plate decreases. The variation of the fracture load with plate thickness rs shown to be a consequence of the fact that the value of the maximum tensile stress at the boundary of the contact area is larger in a thin plate than in a thick plate, for the same indentataon pressure. A method of calculation is described for determining the maxamum tensile stress m an elastic plate subjected to arbitrary symmetrical spherical indentations.

Symmetrical contact problem of a thick transversely isotropic plate

“…The results obtained in Ref. 7 were later employed in an experimental investigation [8]. In the present work, the techniques of the Hankel transform are used to solve the symmetrical problem of the contact between a spherical indenter and a transversely isotropic plate of finite thickness.…”