Glossary Terms

Available in two major types: tungsten high-speed steels (designated by letter T having tungsten as the principal alloying element) and molybdenum high-speed steels (designated by letter M having molybdenum as the principal alloying element). The type T high-speed steels containing cobalt have higher wear resistance and greater red (hot) hardness, withstanding cutting temperature up to 1,100º F (590º C).

General term for various forms of waterjet and abrasive waterjet machining. In all cases, a fine, highly pressurized jet of water cuts and removes the material. See AWJ, abrasive waterjet; waterjet cutting.

Test to determine the behavior of materials when subjected to high rates of loading, usually in bending, tension or torsion. The quantity measured is the energy absorbed in breaking the specimen by a single blow, as in Charpy and Izod tests.

Quality-control approach that monitors work in progress, rather than inspecting parts after the run has been completed. May be done manually on a spot-check basis but often involves automatic sensors that provide 100 percent inspection.

Value that refers to how far the workpiece or cutter advances linearly in 1 minute, defined as: ipm = ipt 5 number of effective teeth 5 rpm. Also known as the table feed or machine feed.

Linear distance traveled by the cutter during the engagement of one tooth. Although the milling cutter is a multi-edge tool, it is the capacity of each individual cutting edge that sets the limit of the tool, defined as: ipt = ipm/number of effective teeth 5 rpm or ipt = ipr/number of effective teeth.

Angle that the cutter edge makes with a plane that is perpendicular to the direction of tool travel. Determines the direction the chip curls.

Measurement of the total angle within the interior of a workpiece or the angle between any two intersecting lines or surfaces.

Replaceable tool that clamps into a tool body, drill, mill or other cutter body designed to accommodate inserts. Most inserts are made of cemented carbide. Often they are coated with a hard material. Other insert materials are ceramic, cermet, polycrystalline cubic boron nitride and polycrystalline diamond.

Assembly machine designed to assemble parts sequentially. Each station consists of tooling for subsequent operations. Parts are moved through their assembly sequence by an intermittent rotary motion.

Method of determining if the primary and secondary reliefs on an endmill or other cutter have been properly ground. See clearance; relief.

Surface-hardening process in which only the surface layer of a suitable ferrous workpiece is heated by electromagnetic induction to above the upper critical temperature and immediately quenched.