Abstract: An abrasive tool insert if formed from a substrate having a face and a continuous abrasive layer having a center, a periphery forming a cutting edge, being integrally formed on the substrate, and defining an interface therebetween. The interface is formed in a sawtooth pattern of concentric rings extending from said center to the periphery. Radially outwardly sloping troughs extending from the center to the periphery are superimposed on the concentric rings. The profile of the interface slopes downwardly from the center to the periphery. The abrasive layer advantageously is diamond and the substrate advantageously is metal cemented carbide.

Abstract: A cutting element is composed of a metal carbide stud having an outer hemispherical distal end which has a series of annular ridges. The tops of the annual ridges are substantially non-planar, i.e., curvilinear, such that the angle formed between the slope on either side is less than 120.degree.. There are no surfaces tangent to vertical on such ridges. A layer of polycrystalline superabrasive material is disposed over the annular ridges. This cutter is easily manufacturable as the metal stud can be pressed and extracted from the punch without further machining and the surface geometry of the metal stud allows for complete PCD compaction during diamond sintering.