The serviceability of the cutting tool appreciably is defined in temperature of cutting. At research of the wear process laws on the tool edge it is rather important to know not only average temperature on its contact platforms but also meaning of temperatures in each point of an edge. In the present work the researches of the laws of distribution of temperatures on a forward surface of an edge are carried out depending on the tool parameters.

For the decision of the specified task one of the most widespread analytical methods - method of sources of heat is used [1]. At a schematisation of components of researched system the tool is submitted as unlimited wedge . Source of heat on a forward surface of the tool edge is submitted as flat rectangular with the sizes bхl equal to a platform of contact of a shaving with a forward surface and with uniform density of distribution of a thermal flow. Advantage of the method of sources is the opportunity to reach of the decision in the analytical kind.

The temperature field on a forward surface of an edge arising under action of a rectangular source of heat in regular intervals distributed on a platform of contact of a shaving with a forward surface bxl at the established heat exchange is described by expression:

Dimensionless function is shown in a fig. 1 as a surface constructed for a source which width b is twice more than length l. Width of a source b represents width cutting, length l characterises length of contact of a shaving with a forward surface of an edge. The submitted diagrams evidently illustrate character of distribution of temperatures on a forward surface of an edge of the tool.

The dimensionless distribution of temperatures on a forward surface of an edge of the tool in a plane perpendicular to main cutting list is defined as follows (z = 0):

Temperature of a forward surface of an edge depends on the tool geometrical parameters and first of all from a forward corner rendering influence on length of contact of a shaving with a forward surface l and density of a thermal flow q:

where V - speed of cutting; PZ0 = Pz - Ffr - difference of cutting force and force of friction on a back surface of an edge; PN0 = Py - Ffr - difference of normal making force of cutting and force of friction on a forward surface of an edge; s - submission, t - depth of cutting; k - factor longitudinal clutch of a shaving.

The distribution of temperatures on a forward surface of the cemented carbide alloy cutters edge with various geometrical parameters - forward corner and back corner is submitted in a fig. 2.

Fig. 2. Distribution of temperatures on a forward surface of an edge of cutters with various parameters

On temperature of a forward surface of an edge the rather essential influence is rendered with properties of a tool material and, first of all, factor of the diathermicness. The accounts of temperatures for cutters equipped with of the cemented carbide alloy plates are executed for the following conditions: a processable material - steel 45, factor k=2,0; modes of cutting - depth of cutting t = 2мм, submission s = 0,4мм/about, speed of cutting v = 120 м/mines., deterioration on a back surface of an edge h = 0,9мм.

The accounts of temperatures for cutters from other tool materials are executed for the following conditions: a processable material - steel 45, modes of cutting - depth of cutting t = 1мм, submission s = 0,1мм/about, speed of cutting v = 120 м/mines., deterioration on a back surface of an edge h = 0,4мм.

The results of account of cutters temperatures are submitted in the table 1.

The table 1- Temperature of a forward surface of a cutters edge from various tool materials

The results of accounts of temperatures on a forward surface of an edge for cutters from various tool materials testify to significant distinction of temperatures depending on properties of a tool material. The cutters equipped mineralceramics have greatest temperature. The diamond cutters have least temperature. Even for one group of tool materials - cemented carbide alloy the distinction in temperatures is rather essential (more than in 2 times) that can be taken into account at the analysis of the tool operation conditions. The developed technique is applicable for definition of temperature fields of various tools. Established on an example of the cutters the laws of influence of geometrical parameters on distribution of temperatures on a forward surface of an edge can be distributed on any tools. The features of various kinds of processing are taken at account of density of a thermal flow and length of contact of a shaving with a forward surface of an edge. On the basis of the received results the recommendations at the choice of a tool material and rational parameters of the tool are developed.

The list of the literature: 1. Резников А.Н., Резников Л.А. Тепловые процессы в технологических системах. - М.: Машиностроение, 1990. – 288с.

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