The Effect of Finishing Milling Parameters on the Physico-Mechanical Properties of the Structural Steel Surface Layer of Aircraft Parts

Abstract

In modern conditions, a technological milling process of aviation parts implemented on a new generation of CNC machines using carbide cutting tools with hardening coatings modified with nanomaterials, high-speed milling applied for parts made of metal structural materials is of particular importance. High-speed milling differs from traditional milling by increasing the cutting speed by 10 times or more. Increasing the cutting speed and changing a number of other parameters of the high-speed milling process leads to a significant increase in cutting zone temperature and a change in the physico-mechanical properties of the sample surface layer, different from those that arise during traditional milling processing. In turn, the state of the surface layer affects the performance characteristics of parts – strength (static, cyclic, impact), wear resistance, resistance to corrosion, erosion and cavitation. A significant increase in the performance of high-speed milling is achieved by fulfilling the conditions for the correct selection of the cutting tool for the type, condition and configuration of the processed material surfaces, as well as determining the optimal parameters for high-speed milling, which maintains high performance characteristics of aircraft parts. The paper presents the results of determining the state of the surface layer of structural steel samples of grades 30HGSA and EP 817 used for the manufacture of compressor machine blades, sheathing housings, flanges and loaded parts of aircraft structures operating under alternating loads, respectively, after traditional and high-speed milling at different cutting speeds.