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The diamond has a high thermal conductivity, low dielectric constant, high band gap, high hardness, low friction coefficient and other properties, has been widely used in many sectors of the national economy. However, in the current application of the diamond tool, it is usually chosen the low melting point metals (Cu, Sn, Ag, Pb, Zn, etc.) as diamond tools binding agent. Poor wettability of the low melting point metal on the diamond, the diamond particles only mechanically embedded into the base body, the bonding strength is very low, the use of the process, the diamond particles are easily separated and metal matrix, the diamond utilization is only 50% to about 60%. Therefore, it is need to be modified on the diamond surface. Electroless plating does not require a large dedicated equipment and instruments, low-cost, no shape restrictions on the material to be plated, electroless plating plating metal on the surface of the diamond powder is a good choice. Experiment on the particle size of 10μm, the specific surface area of ??0.8930m 2 / g of the artificial diamond degreasing, roughening, sensitization and activation series of pretreatment, the use of nickel chloride was added dropwise and also drop chemical plating Ni-B and Ni-Mo-B. According to L 16 (4 5 ) orthogonal experimental arrangements experiments, using the gravimetric method to calculate the relative deposition rate, electroless plating Ni-B and Ni-Mo- The concentration of each component of the solution B, and access of the relative deposition rate of the best plating process conditions, and were characterized by SEM and XRD after plating diamond coating morphology, composition. SEM images of electroless nickel plating that: a nickel-plated coating was sporadic the floc, serious leakage plated; After four nickel-plated coating significantly reduced leakage plating, coating evenly, but the coating there is a small amount of pinhole; dropped in at the same time By way of chemical plating, the nickel spherical leakage plating coated on the surface of the diamond particles, the size of the nickel particles uniformly less. The XRD tests show that the coating composition for Ni and Ni 2 B. Electroless plating Ni-Mo-B, facilities plated nickel chloride solution dropwise and also drop way. The SEM shows: single electroless plating material mainly in powder form, the small particles of diamond have a small amount of shape rules is not deposited on the coating, but the fine diamond particles does not occur agglomeration; four post-plating, the plating thickening than a single chemical plating uniform, coating predominantly loose scaly, a very small amount was flocculent after the plating of the diamond powder is uniformly good, no large particles reunion; dropwise manner electroless plating, plating sporadically coated diamond surface, most of the diamond surface is not deposited on the coating. XRD measurement of the plating layer of Ni-Mo component is mainly Ni and Ni 2, B, which contains a small amount of Mo.
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