SELECTED PROBLEMS OF MICRO-SMOOTHING PROCESS IN EXTRA LOW TEPERATURES Wojciech Kacalak, Mariusz Kasprzyk, Tomasz Krzyżyński, Ryszard Lewkowicz, Ryszard Ściegienka ∗ 1. INTRODUCTION The present development of new areas of technology results in significant interest in new production technologies of micro and nano-machining. Research activities in such areas as a construction and application of fine measuring devices, medical equipment, mechatronic systems, computer elements, mass store devices, micro-robots and micro- devices, become more and more important. Nowadays, high requirements do not refer only to a quality and accuracy of work only. More attention is paid to physical features of machined surfaces. In order to satisfy these highest demands, the final surface shaping should be realized in conditions yielding low level of machining energy. This, in turn, makes it possible to avoid undesirable phenomena like physical changes in outer layer, tensile stresses, changes in chemical constitution. This is one of the reasons of looking for new technologies that could satisfy such conditions 1, 2 . In many cases, especially in a case of machining materials for which in normal machining conditions it is very difficult to obtain high surface smoothness, it can be necessary to apply vacuum technologies and cryogenics. Investigation of a micro-cutting process in low temperatures (up to 100 K) constitutes a part of a project aimed at the elaboration of fundamentals of new technologies of micro-grinding hard-machined materials. Such technologies make it possible to obtain an accuracy of rank 0,1 μm, and to promote decreasing the stress in outer layer. ∗ Department of Fine Mechanics, Faculty of Mechanical Engineering, Koszalin University of Technology, Racławicka St. 15-17, 75-620 Koszalin, Poland