STUDIES ON WEAR MECHANISM OF WIDALON TK 15 IN MACHINING INCOLOY 800

Abstract

„erogns turbine engines require the use of materials which are ablo to operate under th;; conditions of high stresses at high temperatures. A typical example of such a material is Incoloy 800— a nickel alloy. But, it is a difficult—to—machine material. The problems in machining this alloy are deformation of the cutting edge, diffusion between tool and work material, built—up—edge formation, surface cracking of the workpic:ce, distortion and work hardening of tho work material and formation of segmented chips Maoycoated carbides have been developed to machine such difficult—to-machine materials. Recently WID;',LON, a multicoated tool, has been developed by VWIDIA.In this work the wear pattern of WIDALON cutting to: is in machining Incoloy 800 have been studio ci. The results show that the principal wear mechanism of WIDALON TK 15 loading to flank wear and crater wear is attrition. Primary grooving and chip notching due to attrition has also boon notico<<. Its comparison with an un-coated TH 10 tool having positive clearance angle showed that the i^erformanco of TH 10 tool at 36 mpm and 55 mpm is better than tVIDALON TK 15 having 6 clearance angle. Uncoated TH 10 tool showed signs of attrition, plastic deformation and chemical reaction between tool and workpiece.