'Zero radius' laser forming of tungsten carbide/superabrasive cutting edges and teeth

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"We will use innovative additive manufacturing to radically update the process for forming hard teeth on saw blades. The most commonly used tooth tip material is tungsten carbide. In a typical tipped blade less than 1% of the high value wear material is used. The rest is machined off during the manufacturing process or left on the base and discarded when the sharp edges are worn.State-of-the-art tungsten carbide tipped (TCT) teeth are currently formed by welding pre-formed tungsten carbide inserts to steel strip and then grinding these to a sharp edge. The need to manipulate individual inserts means that fine-toothed metal-cutting blades ( \>6 Teeth Per Inch) cannot currently be manufactured. The grinding process is environmentally wasteful - of materials, energy and coolant.Our new process uses micro laser metal deposition (micro-LMD) of the tip material to form the hard cutting edge, thus avoiding the need to manipulate and weld TCT inserts. In LMD, a jet of powder (eg tungsten carbide) is directed at a surface while being simultaneously melted into the surface by a focused laser beam. We have obtained two patents on tooth-making via LMD. With our subcontractor ManuDirect we have experimented with micro-LMD in a test rig and have been able to achieve hard surfaces on teeth and proved their ability to cut.The edges of these teeth are still rounded; we are not yet able to form a sharp 'zero radius' cutting edge. However, once we are able to do so, we will have created a near-net-shape tooth, reducing or eliminating the need for subsequent grinding, or even permitting laser sharpening.Our process should also be applicable to all types of blade and other metal-ceramic combination. However as tungsten carbide is the most widely used abrasive it is our initial focus. The greatest opportunity will be in fine-toothed metal-cutting blades ( \>6 TPI) where there is currently no possibility of using TCT inserts and conventional bimetal blades blunt easily. In addition, we see an opportunity for a wood cutting saw blade that sits in the gap between bimetal and TCT in terms of cost and performance.The lead partner is a manufacturer and exporter of abrasive saw blades and will exploit the process through its customer base. The consortium includes a powder supplier, the UK's leading university in this area and a subcontractor that is expert in micro-LMD equipment."