Study On Chip Breaking Performance Of HSS Turning Tool With Laser Cladded Chip Breaking Dot

Chip breaking is one problem in cutting processes.Continuous,unbroken chips tend to tangle with workpiece or cutting tool in machining processes,which will decrease machined surface roughness of workpiece,reduce the efficiency of production,shorten the tool durability and even endanger the safety of the staff.Thus,chip breaking is an essential aspect of chip control during machining.The primary task of chip control is to solve the problem of chip breaking.So it is very important to adopt reasonable chip breaking methods.Chip breaker with a raised dot was fabricated on the rake face of high speed steel(HSS)turning tool using laser powder cladding method.Based on chip breaking condition and chip breaking dot position conditions,three position equations of laser cladded chip breaking dot were established.The theoretical position regions of laser cladded chip breaking dot on rake face of tool were determined.Turning experiments of aluminum alloy were carried out.Chip breaking processes were observed with high-speed camera.Turning tool with laser cladded chip breaking dot has effective chip breaking ability.The calculated position regions of chip breaking dot are in good agreement with the experimental results.Experimental also results showed that if the center coordinates of chip breaking dot was located in the position region,then chips could be broken effectively and classified as four kinds,i.e.,spiral chips,discontinuous chips,C-shape chips and helical chip segments.Among the four kinds of chips,spiral chip was the greatest in number and broken due to the flank.If the center coordinates of chip breaking dot was located in the transition position region,then chips could not be broken effectively all the time and classified into two categories,helical chip segments and long,cylindrical helical chips.Helical chip segments were broken due to the flank,while the breakage of long,cylindrical helical chips was caused by periodic swing.In summary,the position regions could provide reference for the fabrication of laser cladded chip breaking dot on rake face of cutting tools.