559 Каталог SUMITOMO 2018 Инструмент металлорежущий Пластины Резцы Фрезы Сверла Стр.N3

Каталог SUMITOMO 2018 Инструмент металлорежущий Стр. N3 0559 Lab2u

Technical Guidance Tool Failures and Tool Life Forms of Tool Failures Cat. No. Name of Failure Cause of Failure Resulting from Mechanical causes 7 6 Ol Flank Wear Chipping Fracture Due to the scratching effect of hard grains contained in the work material. Fine breakages caused by high cutting loads or chattering. Due to the impact of an excessive mechanical force acting on the cutting edge. Resulting from Chemical reactions 8 9 10 11 Crater Wear Plastic Deformation Thermal Crack Built-up Edge Swaft chips removing tool material as it flow over the top face at high temperatures. Cutting edge is depressed due to softening at high temperatures. Fatigue from rapid, repeated heating and cooling cycles during machining. Work material is pressure welded on the top face of the cutting edge. Tool Wear Forms of Tool Wear Bad chip control Cutting edge fracture t Creater wear Kt Poor surface finish t Face flank wear VN2 Edge wear Vc Poor machining accuracy Burrs occur Burrs occur Flank wear Crater wear x- Initial wear Sudden increase 1 in wear Steady wear Cutting Time T (min) Cutting Time T (min) Wear is rapid initially, then it proceeds more gradually in proportion with cutting time until a certain limit, beyond which it increases rapidly again. Crater wear is more progressive with no sudden breakdown pattern. Tool Life (V-T) Measure the relative tool lives of the specified wear, over a range of cutting speeds, then plot the tool life along the X-axis and the cutting speed along the Y-axis on a double logarithm graph. Flank wear Crater wear > > V3 y / / V4 / / / /, ii T2 T 3 T 4 Cutting Time T (min) > Kt V- V2 / V3 V4 £ 'r- T2 T'3 T'4 Cutting Time T (min) Ti T2 T3 T4 Tool life (min) T2 T'3 T'4 Tool life (min) T- N3 Technical Guidance