Page 16 - Demo

14 ISCAR CUTTING MATERIALSCutting MaterialsTo ensure correct cutting action the tool cutting part should be made from the appropriate material. In machining, the wedge-shaped profile of the cutting part is under considerable mechanical and thermal loads that cause wearing of the flank and the face of a tool. Therefore, the cutting part material, referred to as the cutting material or tool material must meet specific requirements such as:%u2022 harder when compared to machined material%u2022 have the required hot hardness to ensure necessary hardness at elevated temperatures that feature cutting%u2022 provide high strength%u2022 facilitate wear resistanceIn addition, cutting material should be machinable to enable producing the necessary cutting shape by existing technological processes.The common cutting materials are:%u2022 high speed tool steel (HSS)%u2022 cemented carbides%u2022 cermets%u2022 ceramics%u2022 cubic boron nitride%u2022 cubic boron nitride and diamondCubic boron nitride and diamond are often referenced to as super hard, ultra-hard,or extra hard cutting materials.Whittling Wood by a Jackknife (2)Let%u2019s get back to carving boats with a penknife. Imagine that somebody would like to try a letter opener knife instead of the penknife. If the letter opener is made from wood or plastic, the result will be negative: the opener simply will not cut. On the other hand, applying a letter opener from steel will not provide desired result due to difficulties in carving. Both cases illustrate a wrong tool choice. In the first case the knife materials were not hard enough to ensure proper cutting action, in the second case despite acceptable tool material the cutting geometry failed to meet the requirements of the operation.