磨削工艺对硬质合金切槽刀片刃口质量的影响

The Effect of Grinding Processes on Cutting Edge Quality of Carbide Groove Inserts

本文采用树脂结合剂金刚石砂轮磨削硬质合金切槽刀片的断屑槽和周边,形成刀片的切削刃口。采用D46和D64两种不同粒度的砂轮分别制备了5°、10°、15°前角的切槽刀片。在断屑槽的磨削过程中,采用了一次磨削和两次磨削两种方式。通过表面粗糙度仪测量了断屑槽和周边的粗糙度值,通过SEM测量了刀片的刃口缺陷。结果表明:砂轮粒度磨削周边对表面粗糙度的影响不大,断屑槽磨削的表面粗糙度受粒度影响较大;刀片前角越大,刃口完整性保持越差;相同条件下断屑槽采用两次磨削能获得更好的刃口质量。通过此试验,明确了生产现场磨削此类刀片的磨削工艺:磨削周边选用D64砂轮以提高加工效率,磨削断屑槽选用D46砂轮两刀磨削以提高表面质量,最终在兼顾磨削效率和质量的条件下可获得较好的刃口质量。

In this paper, a resin bonded diamond grinding wheel was used for grinding groove and profile of the cemented carbide grooving inserts and forming the cutting edge. D46 and D64 grinding wheels with different grain sizes were applied to grinding the groove and profile of inserts, respectively. Groove structures with 5, 10 and 15° rake angles were grinded by one time and two times, respectively. Groove and profile surface roughness were measured by surface roughness measuring instrument. Cutting edge defects of inserts were measured by SEM. Resluts show that the grain size of grinding wheel has little effects on the profile surface roughness, while the groove surface roughness is sensitive to grain size. The integrity of cutting edge becomes worse with the increase of rake angle. Under the same conditions, better cutting edge quality can be achieved by two times grinding than one time grinding. It is determined that D64 wheel is applied to grinding profile to improve machining efficiency and D46 wheel is applied to grinding groove to improve the surface quality. Good edge quality with higher grinding efficiency can be obtained by this grinding process for this kind of groove inserts.