Effect of the contact conductivity of the diamond–metal binder interface on the thermal conductivity of diamond-containing composites

Abstract

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.

Thermal conductivity of bulk nanocrystalline nickel-diamond composites produced by electrodeposition

“…The obtained thermal conductance value in [34]. This value is approximately 5% of the theoretical thermal conductance between nickel and diamond.…”

“…2a shows an SEM micrograph of the as-received diamond particles. As indicated by the manufacturer, the particle shapes are mostly cubo-octahedral with 8 hexagonal/triangular (111) sides and 6 quadrilateral (100) sides [34]. The size distribution as determined from SEM micrographs of the diamond particles is shown in fig.…”

“…This value is approximately 5% of the theoretical thermal conductance between nickel and diamond. However, the matrix in the experiment of Shmegera et al [34] was not pure nickel. Unfortunately, to the best of our knowledge, experimental data on the thermal boundary conductance between pure nickel and diamond are not currently available.…”

Intensive electro sintering of diamond composites with multicomponent Ni-Sn based binder

“…Deposition of chromium on the surface of diamond increases effective thermal conductivity of diamond composite with Ni + 6%Sn binder by 15 -25%, that is a probable consequence of interface chemical reactions. The obtained data were interpreted with aid of the micromechanical model of composite with imperfect interface [14] predicting the effective thermal conductivity of composite as well as evaluating the interface contact conductivity by solving the inverse problem. It has been found that adding Cr increases the contact thermal conductivity of diamond-binder interface tenfold, from 2.1·10 6 to 2.3·10 7 W/(m 2 •K) [14] being typical value for chemical bonding case [15].…”

“…The obtained data were interpreted with aid of the micromechanical model of composite with imperfect interface [14] predicting the effective thermal conductivity of composite as well as evaluating the interface contact conductivity by solving the inverse problem. It has been found that adding Cr increases the contact thermal conductivity of diamond-binder interface tenfold, from 2.1·10 6 to 2.3·10 7 W/(m 2 •K) [14] being typical value for chemical bonding case [15]. [16], which consists in conducting a series of tests ( fig.…”