Protvino Branch of Luch Research & Production Association, Protvino, Moscow Region, Russia:

A. F. Avtushenko, Head of Department

V. B. Usachev, Director

S. P. Korolev Rocket and Space Corporation Energia (RSC Energia), Korolev, Moscow Region, Russia:
А. А. Basov, Division of Thermal Control Systems, Chief, Candidate of Technical Sciences, e-mail: Andrey.Basov@rsce.ru

Experimental Machinebuilding Plant of RSC Energia (CJSC), Korolev, Moscow Region, Russia:

I. E. Maltsev, General Director

This paper examines some aspects of minimizing thermal resistance in the heat transfer zone of the base element of an advanced dual-phase heat control system designed for a large energy-rich new-generation module of an orbital space station. Using imaging data, the authors analysed techniques ensuring thermal contact in vacuum between the mating elements of a heat exchanger made of dissimilar aluminium alloys. They include use of heat-conducting pastes and glues, thermal pressing, welding, gas dynamic cold spraying, soldering. The paper describes specific preparation procedures, as well as how to choose the solder alloy, the temperature regimes of vacuum soldering and the operating regimes for the vacuum plant to ensure the most effective soldering process. Application of the proposed soldering technique on the aluminium alloys AMg6 and AD31 resulted in an almost complete fill with highly heat-conductive solder of a radial gap of 0.1 mm between the mating parts on a section of ~400 mm. By means of non-destructive testing, it was confirmed that the dry joint did not exceed 3–7% in a batch of more than 200 similar heat exchangers.

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