DIAMOND COVERING ARTICLE WITH INTEFRALLY FORMED WEAR INDICATING DEVICE

摘要

A diamond-coated article comprises a first, electrically-conductive diamond layer (14) disposed on a substrate (12) and a second, electrically-insulating diamond layer (16) disposed over the electrically-conductive diamond layer (14). The article may be fabricated by a process including the steps of forming a thin, electrically conductive layer (14) of diamond immediately adjacent to the surface of the substrate (12) of the diamond-coated article, followed by further formation of electrically-insulating diamond material (16) on top of the electrically-conducting layer (14). A method for indicating wear of the article comprises the steps of passing a current between the tool and the workpiece and detecting a change in the flow of current caused by exposure of the first diamond layer (14). Another diamond-coated article comprises a first diamond layer (74) having first optical properties disposed on a substrate (72) and a second diamond layer (76) having second optical properties disposed over the first diamond layer (72). The article may be fabricated by a process including the steps of forming a first layer (74) of diamond having first optical properties immediately adjacent to the surface of the substrate (72) of the diamond-coated article, followed by further formation of a second diamond layer (76) having second optical properties on top of the electrically-conducting layer (74). A method for indicating wear of the article comprises the steps of directing light at the surface of the article and detecting a change in transmission, reflection, scattering, or other optical property of the diamond wear layers (76).