Description
Modern manufacturing processes place high demands on cutting tool materials. Therefore, a constant improvement and redevelopment of these materials is needed to meet their demands. A disadvantage of modern high-performance cutting tool materials such as cemented carbides or polycrystalline diamond (PCD) is that they require rare materials and large amounts of energy for their production [1]. In addition, the partially critical availability of raw materials such as tungsten or cobalt poses a further challenge. Due to this and the high price of such materials, there is a high need to recycle and substitute them. This is especially true for regions where cutting tools are produced but where the raw materials are not mined like the USA [2] or the European Union [3, 4]. Therefore, research projects aim to fnd ways to substitute these critical raw materials [5] or to identify suitable alternative cutting tool materials [6]. In order to meet these challenges a cutting tool material with a high (global) availability, a low energy consumption in the production process and low raw material prices is required. Natural rocks could pose such an alternative. Rocks have a high global availability due to a large number of comparatively easily accessible deposits all over the world. In addition, the use of rocks means that complex und energy-intensive preparation and production processes for the cutting material can be dispensed with, as the cutting material rock is already available in nature in the required state. Compared to the production of a kilogram of conventional cemented carbide, for example, this would save between 290 and 480 MJ-equivalents of energy. In addition, this would also mean a reduction in emissions of climate afecting gases in the order of 10 to 19 kg CO2-equivalents [1]. Overall, the use of rock as a cutting material could therefore provide the tool industry with a cost-efective alternative with high availability and a low energy demand in production compared to conventional cutting materials. At the same time, this would support the industry’s shift towards greater sustainability, which is necessary with regard to climate change. So far, however, no systematic investigation of the usability and suitability of natural rocks as cutting tool materials has been carried out.
