THE MODEL OF THE CONSTRICTION RESISTANCE OF A SLIDING ELECTRICAL CONTACT

This article is devoted to a theoretical study of the processes in a sliding electrical contact and the derivation of the formula for constriction resistance in the transient layer of electrical sliding contact taking into account the fractal heterogeneity of contact current-transmitting clusters, as well as the verification of the obtained theoretical formulas using a static experimental plant.

PREPARATION OF GRADATED NANO-TRANSIENT LAYER AT INTERFACE BETWEEN DEPOSITED FILM AND SUBSTRATE BY HIGH-INTENSITY PULSED ION BEAM IRRADIATION

We prepared gradated nano-transient layers at different interfaces between deposited film and substrates by high-intensity pulsed ion beam (HIPIB) irradiation. The deposited film was ( Al–Si ) alloy and substrates were Ni and Ti , respectively. The gradated nano-transient layers at different interfaces were measured by Rutherford backscattering, its spectra were solved by SIMNRA code and then the microstructures of the gradated nano-transient layers at the interfaces of these two irradiated samples were obtained. The experimental results were analyzed by STEIPIB code. The formation of the gradated distribution of element contents in nano-transient layer at the interface can eliminate the abrupt changes of thermal and elastic characteristics at the interface. And, it can greatly reduce the mismatch of thermal expansion coefficients and Young's modulus at the interface between deposited film and substrate. Thus, after the formation of the gradated nano-transient layer, the adhesion at the interface between different materials can be enhanced and the level of thermal stresses can also be reduced in the case of thermal loading.