In the following master thesis study of milling process using ceramic end milling tools is presented. Tool life of ceramic end milling tools is compared with tool life of more widely used carbide end milling tools, when milling two different hard-to-cut materials under different cooling conditions.
Tools are exposed to high stress and loads when they are used to machine hard-to-cut materials, which in many applications results in shorter tool life. There are many reasons why this happens, one of them is fact, that hard to cut materials usually have low temperature conductivity, there is often built up edge material present when cutting, then there is deformation hardening... All of these workpiece material properties and phenomena contribute to shorter tool life. The purpose of the experimental work was to determine machining ability of two different end mills. We used ceramic and carbide end milling tools to mill Nickel based super alloy Inconel 718 and stainless steel 316L under different cooling conditions. Through experimental work, tool wear and tool life was measured and the shape of chips was observed. Cost analysis was carried out for experiments which showed best results.
Longest tool life was achieved using ceramic end milling tools in dry cutting conditions, on the other hand carbide tools performed better using flood cooling. Ceramic end milling tools showed some advantages over carbide tools, but their price is much higher which resulted in higher overall machining cost, therefore ceramic end milling tools should be used only for milling hard to cut materials.
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