Abstract
Orthogonal cutting tests were conducted on an aluminum cast Al-Zn-Mg alloy having good machinability and little trouble in tool wear. The cutting temperature was experimentally examined with respect to the cutting speed, behavior of built-up edge, tool-chip contact length, etc.
The results obtained were summarized as follows.
In the range of cutting speed 20320m/min., the relation between cutting temperature and cutting speed was expressed by a straight line both in terms of logarithmic scale. The cutting temperature was linearly elevated with the increase of the cutting speed, but it was abruptly inflected in the midway. The coefficient of linear elevation of temperature was considerably small for the cutting speed beyond the above inflection point. The cutting temperature corresponding to the inflection point was higher with the increase in the depth of cut. The cutting speed corresponding to that point was higher with the decrease in the depth of cut, and it approximately agreed with the value at which the thickness of chips was maximum. The aspect of built-up edge in this state was varied according to the depth of cut. There would be no special correlation between the cutting speed or cutting temperature and the behavior of buit-up edge. The temperature of disappearance and the behavior of built-up edge depended upon the other cutting conditions such as the depth of cut, rake angle, etc. as well as the cutting temperature.
