アルミニウム合金の穴加工精度におよぼす給油法の影響

抄録

The forced, mist, and conventional lubricant supply methods were applied to a drill with an oil supply hole and a pointed chisel edges. The effect of the above lubricating methods on the hole accuracy was examined in terms of the hole oversize, the surface roughness and the height of burr. Although a soft alloy did not discriminate the lubricating methods, the forced lubrication was most efficient in the drilling of a hard alloy. When the drilling was performed under the severe condition, the effect of the forced lubrication was prominent. It was found that the hole accuracy was improved irrespective of the lubricating method, if the outer corner of the drill lip with a large relief angle was rounded to an adequate degree.