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The basic hypothesis of this article focuses on the study changes in mechanical properties of stainless steels XCr17Ni7MoTiN under surface finish when drilling. The problem of drilling holes with diameter D=10 mm resides in the fact that 30 to 40% of these holes do not comply with prescribed requested requirements. This article presents the results of experiments focusing on the study of the damage process in helical drills with diameter d=10.0 mm when drilling into austenitic stainless steel XCr17Ni7MoTiN. This study also includes an analysis of accompanying phenomena in the cutting zone by measuring some selected parameters. Experimental results were verified in the production of holes in products for the food industry.

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Durability of the cutting tools is very complex process that is influenced by more factors. To the Identify these factors is necessary execute many experiments. The technical science defines the basic method for determining durability of the cutting tool according to results and knowledge F. W. Taylor. The Literature from renowned authors indicates that durability of the cutting tool is defined on the base of T-vc dependence. T-vc dependence like a elementary durability dependence was described according to Taylor´s graphics dependence VB=f(s) for different cutting speeds in 1906. From this theory were later derived others theories, that became the basis of theories durability of cutting wedge for the different cutting materials. For the durability identification of the cutting tool are in technical practice used two basic tests. The First is the short-term durability test and second is machining long-term test method. Both these tests have some advantages and some disadvantages that are described in Introduction of this paper. This paper describes how to create and analytically express new durability dependence for ceramic cutting tool on the base of vc-VB dependence. This dependence consists from vc - cutting speed and VB - criterion of blunting. The whole procedure and its analytical expression is the subject of this paper.

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Durability is very important property of every cutting material. This property of cutting materials defined theirs life-time. Technical science defines a lot of different factors, that they may be cause of shorter life-time of cutting tool. Maximally possible elimination of these factors is necessary for optimization of cutting materials life-time. Durability of cutting materials is defined in standard ISO 3685. The main part of standard ISO 3685 is T-vc dependence definition for selected cutting materials. One of these cuting materials contained in this standard is cutting ceramic. Standard ISO 3685 contains instructions how to create T-vc dependence for cutting tools made of cutting ceramic. In this standard are only instructions how to create T-vc dependence according to Taylor, but last part of every experiment is analytical expression of tested dependence. The article describes process how to define and analytically express T-vc dependence for cutting ceramic (Al2O3).

This article presents the results of experiments that concerned on the surface roughness quality by drilling of a new Extra Low Carbon (ELC) austenitic stainless steel X01Cr14Ni9TiN. This article presents conclusions of machinability tests on new austenitic stainless steels X01Cr14Ni9TiN. The results of cutting zone evaluation under cutting conditions (cutting speed in interval vc=40-60 m/min, depth of cut ap=2.5 mm and feed f=0.01-0.12 mm per rev.).

Technical science defines a lot of different factors, that they may be cause of shorter cutting tool lifetime. For increase of cutting tool durability is necessary maximally possible elimination of these factors. Determination of cutting tool durability is very important, because provides comprehensive information how to determine appropriate technological conditions for selected cutting tool. The analytical expression of dependence represents very important part of experiments, because all tested processes can be described and defined by formula. These instructions, how to proceed in experiments are obtained in standard ISO 3685. Very important and often used standard ISO in engineering practice is standard ISO 3685. The main part of this standard is T-vc dependence for cutting materials. In standard ISO 3685 are included cutting materials made of high speed steel, sintered carbide and cutting ceramic. The article describes process how to define and to analytically express T-vc dependence for cutting tools made of ceramic in machining process of steel 80MoCrV4016.