S. P. Korolev Rocket and Space Corporation Energia, Roscosmos, Korolev, Russia:

A. A. Basov, Head of Department, Candidate of Technical Sciences, e-mail: Andrey.basov@rsce.ru

Moscow Aviation Institute (National Research University), Moscow, Russia:
Yu. D. Koziner, Associate Professor, Candidate of Technical Sciences
D. A. Kravtsov, Senior Lecturer, e-mail: kravtsovda@mai.ru

A. A. Pozhidaev, Assistant Lecturer

N. A. Pilyugin Research and Production Centre for Automation and Instrumentation, Roscosmos, Moscow, Russia:
I. E. Maltsev, General Director

One of the important problems of using additive technology for making complex geometry parts with poorly accessible internal surfaces includes that of removing residual poorly sintered powder particles from such surfaces. This paper examines the physical process of ultrasonic cleaning, describes the procedure and the required equipment. The paper also describes the results of a study that looked at the efficiency of applying such procedure in the case of poorly accessible internal surfaces of a conductive/convective heat exchanger made of aluminium alloy by selective laser melting. The study aimed at confirming that a combination of ultrasonic vibration and a potassium hydro xide (КОН) solution used for pickling make the separation of poorly adhering powder particles significantly more intense. In the course of the study, relationships were established between the pickling rate (the rate at which poorly adhering particles are removed) and the concentration of the solution used and the presence of superimposed ultrasonic vibrations. It was found that the cavitation effect that occurs in liquid caused by ultrasonic vibrations does not impact the cleaning process or cause erosion of the heat exchanger walls or change their roughness.

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