EFFECT OF SUBSTRATE SURFACE PREPARATION ON THE PERFORMANCE AND LIFE OF TIN-COATED HIGH-SPEED STEEL CIRCULAR-SAW BLADES

Advanced surface engineering technologies have been successfully appli ed to high speed steel and carbide single-point cutting tools. Limited benefits have been achieved when applying the same technologies to mu ltipoint cutting tools of commercial quality. In this application, poo r substrate surface preparation is a major contributor to premature fa ilure of the tool. The current work investigates the effect of substra te surface preparation on the performance and tool life of titanium-ni tride-coated high speed steel circular saw blades when machining tool steel under accelerated cutting conditions. Tests have been developed to allow the cutting action of a full circular saw blade to be replica ted by simulation tests using a segment containing representative teet h. Segments which were untreated or had a TiN coating applied onto eit her a microblasted or a surface ground substrate were tested for perfo rmance and life at an accelerated cutting speed. Results indicate blad e life improvements through careful preparation of the substrate surfa ce prior to coating. Benefits of substrate surface preparation in enha ncing the life of TiN-coated circular saw blades have been established . This information will be useful in developing a total systems approa ch by which advanced surface engineering and cutting tool technology c an be jointly applied to develop an improved product.