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The effect has been studied of the contact conductivity of the diamond-metal binder interface on the thermal conductivity of diamond containing composites having two and three component nickel based metal binders. A device and procedure have been developed for measuring the thermal conductivity coefficients of binders and based on them diamond containing composites. The dependence of the ther mal conductivity coefficients on the compositions (particularly, the presence of the carbide forming addi tives) and structures has been analyzed. A theoretical model of the composite has been proposed, which allows for the real shape of a diamond crystal and contact conductivity of its faces. The estimation of the thermal contact conductivity of the interface has been derived by solving the inverse problem. It agrees sat isfactory with the literature data on direct physical studies and similar estimates for composites with alu minum and copper binders. The influence of the contact resistance on the temperature mode of the dia mond tool operation has been indicated by the results of modeling.

A procedure of multiple indentations has been proposed as a promising method of studying surface properties of structurally heterogeneous bodies. It has been shown that this procedure is applicable to a wide spectrum of multiphase (including superhard) materials, ceramics, and metals and makes it pos sible to assess mean properties of separate phases and a composite as a whole as well as a degree of the sam ple hardness inhomogeneity at various scale levels. Such information is important in prediction of the wear and machinability of structurally heterogeneous materials. Experimental and model results that verify the efficiency of the procedure have been presented.