Quality for perfect layers

Thousands of machine shops around the world have specialized on demanding milling assignments. But what happens when a customer asks if a firm can also machine composite materials? That isn’t as rare as some people might think. Experts estimate that the market for fibre-reinforced plastics has grown by 40% since 2004 and will almost double again by 2013. This was reason enough for LMT to set up its own competence centre for the machining of composites and to pool the experience and expertise of the specialists at LMT Onsrud and LMT Belin.

At the LMT Technology Days symposium Onsrud will be presenting a new a diamond film-coated compression tool for machining composite materials. Here the experts in the USA have relied on their tried and tested design for tools with intersecting cutter geometry. This spiral design means that the upcut and downcut spiral flutes intersect from both directions and push the individual layers of the composite material together during machining so that the layers cannot separate from one another. This action prevents delamination not only to the upper and lower covering layers of the material, but also between the inner layers that are hidden from view. Additionally, the PCD coating protects the tool against the wear caused by these highly abrasive materials. For the new cutters, which are individually tailored for specific tasks, Onsrud recommends run parameters of 6,000 rpm and 2 metres per minute for a 12 mm diameter tool.