Study of chip breaker. Development of new chip breaker suitable for wide cutting conditions.

It is well known that the continuous chips cause various troubles in turning of the steel. So the chips should be broken into short segments. In this case, the chip breaker is generally applied very well. However, the commercial chip breaker is difficult to break the continuous chips under the wide cutting condition. The chip breaker for finish turning is different from that for other usual turning. In order to find out a more effective chip breaker configuration than the commercial chip breaker in turning, a new chip breaker is investigated experimentally at a constant cutting speed of 3 m/s. The first chip breaker configuration is classified in negative lead step former. This chip breaker is effective for the low feed and the small depth of cut. The final chip breaker configuration has been developed, combining negative lead step former with positive lead step former. The final chip breaker is effective for a wide set of cutting condition. That is, in turning of SS 41 steel this chip breaker can break the chip into small segment in the following cutting conditions ; the feed rate from 0.05 mm/rev to 0.51 mm/rev and the depth of cut from 0.1 mm to 3.0 mm.