Abstract
In order to get a good cutting condition for machining cast-iron rolls with carbide tools, tool life tests of various rolls such as chilled, ductile, grain and adamite rolls are examined experimentally with carbide tools. The relation between the mean free path of Co-phase and a grain size diameter in microstructure of carbide tool and the tool life is investigated. The main results are as follows : (1) The shorter the length of mean free path is the longer tool life when the abrasive type wear works in machining cast-iron rolls. (2) For the estimation of optimum cutting speed (υ>1200), the nomogram is made by both the length of mean free path of carbide tools and the hardness of cast-iron roll. (3) The diagram of the relation between cutting speed and feed rate is made by the tool life tests in machining ductile-roll. If the length of mean free path of carbide tool and the roll hardness are measured, the optimum cutting condition for machining the ductile-roll is obtained by both the nomogram and the diagram. (4) The adaptability of carbide tool on the roll-cutting depends upon the length of mean free path of Co-phase and the mean grain size diameter of carbide particle. Therefore, these values are useful for the selection of roll-cutting condition.
