Cutting characteristics of niobium plates using for acceleratator cavity

Cutting experiments were conducted to investigate cutting characteristics in Niobium plates. Niobium is used for a super conductivity material such as an acceleratator cavity because of its high conductivity, ductility and anti-corrosion property. However, mechanical engineers are unfamiliar with not only the material properties but also the mechanical properties. Hence, the cutting characteristics have yet been determined. The cutting characteristics such as cutting forces, machined surface properties, chip formation mechanism are not investigated sufficiently. The results indicated that the cutting provided not smooth chip formation as a difficult-to-cut material:less than 30 degree rake angle tools offered unstable chip formation which means alternating change in the cutting forces at the same depth of cut :unstable chip formation resulted in chipping of tool edge. (author)