Performance of cemented carbide tools with physical vapour deposited coatings

Abstract

Close-coupled gas atomizing nozzles are notoriously difficult to design and manufacture to achieve consistent performance. To evaluate nozzles by atomizing molten metal is very costly and time consuming, while simple aspiration tests do not correlate reliably with atomization. John Dunkley of Atomising Systems Ltd (Sheffield, UK) describes the company's use of water to model the molten metal. This allows prediction of metal flow rate, as well as the detection of several atomizing problems.