MACHINING AND WEAR RELATIONSHIPS IN AN ORDERED INTERMETALLIC ALLOY

There are many commonalities between machining (metal cutting) and sliding friction and wear. Machining (lathe-turning) experiments and ball-on-disk wear experiments have been conducted on a nickel aluminide alloy (IC-218 LZr). The wear tests were performed at room temperature and 923 K (650-degrees-C) using tungsten carbide as the slider material to simulate the cutting tool material. The effects of cutting speed, use of a coolant and type of cutting tool on surface finish, depth of workpiece subsurface damage and cutting chip characteristics are reported. The depth of damage in sliding we ar experiments is compared to that for lathe-turning experiments in an attempt to estimate the shear forces on the cut surface. Friction coefficients and wear factors for tungsten carbide sliding on IC-218 LZr depended on the magnitude of the normal force and on the sliding temperature. The wear rate of the nickel aluminide alloy decreased as the temperature increased. The relationships between the observed friction and wear behavior of nickel aluminide and its machining characteristics are discussed.