METHOD FOR MAKING SMOOTH SUBSTRATE MANDRELS FOR USE IN FABRICATING CVD DIAMOND WATER JET NOZZLES

摘要

60SD00578 METHOD FOR MAKING SMOOTH SUBSTRATE MANDRELS FOR USE IN FABRICATING CVD DIAMOND WATER JET NOZZLES Broadly, the present invention is directed to a method for electroplishing elongate metal mandrels in an electrolytic cells, wherein the electroplished metal mandrels are ideally suited for growing CVD diamond thereon for making water jet nozzles and similar flow control devices. The method of the present invention comprises placing an elongate cylindrical mandrel in an electrolytic cell between a pair of centering caps. The cell comprises an elongate annular cylindrical electrode, which preferably is a cathode, and which has open ends in which said pair of centering caps are placed to center said mandrel within said cylindrical electrode. The cell further comprises an outlet and an inlet connected to a circulating source of electropolishing electrolyte. The mandrel and the cylindrical electrode ale connected to a source of electrical power. This electrical power is applied to the mandrel and the cylindrical electrode to establish an electrolytic cell. Finally, the source of electropolishing electrolyte is circulated through the cylindrical electrode to electropolish the mandrel. Another aspect of the present invention comprises the electrode c cell for electropolishing elongate metal mandrels. Such electrolytic cell comprises an elongate annular cylindrical electrode having open ends, and an outlet and an inlet; a pair of centering caps which are placed in said open ends and which caps are adapted to receive an elongate cylindrical mandrel to center said mandrel within said cylindrical electrode; a circulating source of electropolishing electrolyte which is in flow communication with said cylindrical electrode via its outlet and its inlet; and a source of electrical power connected to said mandrel and connectable to said cylindrical electrode. Said mandrel is electropolished by applying electrical power to said mandrel and to said cylindrical electrode to establish an electrolytic cell, and circulating said source of electropolishing electrolyte through said cylindrical electrode to electropolish said mandrel.