| Some factors influencing the performance of diamond saw blade, for example, the bonding strength between diamond and matrix, the average force exerted on the diamond during cutting and the failure of the diamond were studied in this thesis. It was revealed that there exists a four-layer structure in the segment with Ti-coated diamond. By analogy to the fracture strength formula of composite materials, a formula calculating transverse-rupture strength of diamond segment was proposed. According to the basic principles of Quantitative Metallography, a model for estimating the number of diamond truly cutting the object in the contact zone during the cutting process of saw blade was suggested. The preliminary design principles on the diamond characteristics (size, strength, concentration) were proposed. The main factors of diamond failure of the saw blade were analyzed in detail. The main contents of this dissertation include:1.By mean of x-ray diffraction of Ti-coated diamond, scanning electron microscope analysis of diffusion layer between Ti and bonds , and weight loss analysis of some kinds of diamonds, the effect of titanium coated on the diamond on the performance of the saw blade was studied systematically. The effect of titanium-coating parameters and subsequent hot-pressing parameters on the interaction between the titanium layer and the bond was discussed in theory, then a four-layer model for the bonding structure of the diamond coated with Ti was proposed, which was examined by diffusion theory and experiments. By analogy to the fracture strength formula of composite materials, the TRS formula of diamond segment was suggested. The effect of electroless plating nickel ant copper on the titanium layer and the effect of mixed rare earth metal additives were further compared .2.The influence rules of iron, WC, aluminum, mixed rare earth metal additives, nickel, d iamond s ize, s intering temperature and holding t ime o n t he TRS o f diamond segment and cutting performance of the saw blade were revealed by the orthogonal experiment. Some appropriate technical parameters of diamond saw blade for cutting concrete were determined. Performance difference among diamond saw blades were explained by SEM photographs of used diamond segments. The corresponding relationship between the segment hardness and tool life was revealed.3. A model estimating the number of diamond in the contact zone truly cutting the object was established. A more accurate equation was suggested which can calculate the true forces exerted on the diamond in the contact zone, In the light of static compressive strength, the design criterion for three diamond parameters was suggested. The work mechanism of the saw blade with mixed diamonds was expounded by comparing the protrusion height of small-size diamonds with the mean penetration depth of working diamonds.4.The forces on the diamond saw blade and the power of it while cutting No.603 granite were measured by the force-measurement system Lilster 9257 BA and power-measurement system. The critical angle a (or cutting depth Ap) while Fx less than zero is closely related to the friction efficiency theoretically. Main failure mechanisms of diamond abrasives were analyzed in this thesis.5.By means of measuring the hardness, density and TRS of some kinds of bonds and analyzing the existing phases using X-Ray diffraction, the effect of prealloying on dynamics of densification and diffusion homogenization was examined. The mechanism of prealloying was discussed on diffusion theory.6.Taking No.603 granite in Fujian for example, the optimal design steps and criteria for diamond saw blade were proposed. The diamond saw blade after technical optimization exceeds some commercial saw blade in almost all performance.
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