Технічна інженерія (Jun 2021)
Improving the finishing face milling process of flat surfaces of small width parts
Abstract
Face mills equipped with superhard materials find more and more wide application at finishing of high hardness materials. These tools fully reveal the potential at high-speed processing. However, domestic industrial enterprises do not always have metalworking equipment of this level. The consequence of this is using face mills equipped with superhard materials, at irrational low cutting modes, which reduces the processing productivity, the tool life and the deterioration of the quality of the machined parts surfaces. The process peculiarities of finishing the surfaces of small width workpieces (20…50 mm), made from high hardness materials, with face mills, equipped with superhard materials, are investigated in the work. It is shown that the machining process is characterized by non-optimal cutting modes; using milling cutters of small diameter; a small number of cutting elements that simultaneously participate in cutting and degraded dynamics; low tool life of cutting elements; insufficient processing productivity and quality of treated surfaces. It is determined that the processes of finishing flat surfaces with face mills of oblique cutting with the using stepped cutting schemes have significant advantages, which allow us to ensure full participation in the processing of all cutting elements, improve process dynamics and increase tool life. The use of vertex-free geometry with monotonous curvilinear cutting edges allows excluding from the process of microroughnesses formation the most vulnerable part of the cutting edge – the vertex. Ways to increase the processing productivity of small width surfaces by using face mills with increased diameter on non-high speed machines and shifting workpieces relative to the milling cutter axis by a distance that ensures the required height of microroughnesses of the treated surface have been identified.
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