THE EFFECT OF SUBSTRATE SURFACE PREPARATION ON THE WEAR AND FAILURE MODES OF TIN-COATED HIGH-SPEED STEEL CIRCULAR-SAW BLADES

The effect of substrate surface preparation on the performance and too l life of titanium nitride (TiN) coated high speed steel circular saw blades has been shown to be significant [1]. The influence this has on the wear and failure characteristics of the blades is now considered. Previous work by the authors shows TiN coated high speed steel circul ar saw blades benefit from substrate surface preparation prior to trea tment. Cutting test results show that blades which had undergone a mic roblasting process exhibited an increase in tool life. Using testing m ethods developed to simulate the cutting action of full circular saw b lades by using representative saw segments, the effects of substrate s urface preparation are further investigated by identifying and compari ng the wear mechanisms that develop on circular saw teeth subject to v arious preparation/coating conditions. Assessment of the wear and fail ure mechanisms associated with each combination of substrate preparati on/coating have been used to appraise the relative merits of the treat ment, blade design and manufacturing process. The work will assist in the development of a systems approach that combines both cutting tool and surface engineering technologies with a view to developing an impr oved product.