Determination of technological possibilities of machining by temperature criterion

The results of theoretical studies of the cutting temperature at machining are given, taking into account the motion of the heat source deep into the surface layer of the workpiece and balance of the heat flowing into the forming chips and the surface layer of the workpiece. This made it possible to determine the optimum parameters of grinding (the depth of grinding and the speed of the part), taking into account the limitation on the temperature criterion and specific processing capacity. It has been found that with a relatively low specific processing capacity, it is expedient to use multi-pass grinding with an increased speed of the part, and with high specific processing capacity – deep grinding with a low speed of the part. It is shown that taking into account the motion of the heat source deep into the surface layer of the workpiece ensures a more accurate solution of this problem. It has been established that in real grinding conditions the ratio of the preset and maximum grinding temperatures can vary only within the range of 0...0,4 due to the significant excess of the maximum melting temperature of the melting temperature of the material being processed due to a significant increase in the nominal cutting stress. It has been found by calculations that at turning the cutting temperature is always less than at grinding due to the lower power consumption of the treatment (the nominal cutting stress). Therefore, the maximum cutting temperature during turning is determined to be less than the melting temperature of the material being processed. Consequently, the ratio of the preset and maximum cutting temperatures can vary between 0...1,0, i. e. within much larger limits than at grinding. This expands the technological capabilities of the turning process as compared to grinding. It has been shown that the highest processing capacity at a given temperature during turning is achieved under conditions of high-speed cutting