Bartek Stawiszynski
Technical University Berlin, Germany
Title: Study of diamond coated silicon nitrides for the use as milling tool substrate
Biography
Biography: Bartek Stawiszynski
Abstract
Chemical Vapor Deposition (CVD) diamond coated tools are currently successfully used in many applications, for example in the cutting of thin foils, paper and textiles, machining of non-ferrous materials and pressure forming. With the use of cemented carbide as a substrate for diamond synthesis it has to be ensured that the cobalt does not initiate a catalytic reaction of diamond to graphite, this requires a time-intensive and costly pre-treatment process. Because of their chemical composition ceramics do not have these disadvantages and as such possess large potential as substrate materials for diamond coatings. Silicon based ceramics have a high hardness and heat resistance combined with good toughness and thermal shock properties. Currently, there are few scientific studies that investigate the tribological wear resistance of diamond coated silicon nitride ceramics. In this contribution conventional cemented carbide and diamond coated silicon nitrides are studied in model wear and machining tests. Their wear resistance to abrasive and adhesive wear is compared to coated cemented carbides. In addition, the grindability of the ceramics is examined in order to determine which substrates are suitable for a reliable production process for cutting tools. After evaluating the results of plane ceramic samples, milling tools were manufactured, coated with CVD diamond and tested in the machining of fibre reinforced components.