后刀面微织构内冷麻花钻钻削Ti6Al4V的性能研究

2020-11-10

作者：武勇强，郭旭红，张克栋，孟祥峰，张靓单位：苏州大学机电工程学院

摘要：Ti6Al4V具有强度高、导热性低等特点，广泛应用于航空、航天等领域高端装备中。钻削制孔时，在热-力作用下，切削力和切削温度较高，产生严重的刀具磨损，导致加工效率低和加工质量差。本文采用激光技术在内冷麻花钻后刀面制备出平行于主切削刃（PT）、垂直于主切削刃（VT）、倾斜45°于主切削刃（LT）的三种沟槽型微织构，进行Ti6Al4V的钻削试验，对钻削力、切屑形态以及被加工孔表面粗糙度进行研究，并与无织构麻花内冷钻（NT）对比。结果表明：在内冷麻花钻后刀面加工微织构能有效减小钻削力，其中，相对于NT型麻花钻，PT和VT型麻花钻的钻削力降低23%~31%，而LT型麻花钻相对于NT型刀具钻削力降低46%；对于切屑形态，微织构麻花钻能降低切屑堆积性，增加其断屑性能，LT型麻花钻几乎没有缠屑；对于被加工孔的表面质量，微织构麻花钻可有效降低其Ra值，其中LT型麻花钻的粗糙度Ra值达到了1.28μm，比NT型麻花钻降低了约54.4%，综合效果最好。

关键词：微织构；内冷麻花钻；钻削力；表面粗糙度

中图分类号：TG713；TH117文献标志码：ADOI：10.3969/j.issn.1000-7008.2020.10.006

Study on Cutting Performance of Ti6Al4V with Internal Cooling Twist Drill

Microtextured on Flank

Wu Yongqiang，Guo Xuhong，Zhang Kedong，Meng Xiangfeng，Zhang Liang

Abstract:Ti6Al4V is widely used in highend equipment in aerospace and other fields，it has the characteristics of high strength and low thermal conductivity.However，when drilling holes，the cutting force and cutting temperature are high under the action of force and heat，resulting in serious tool wear，low machining efficiency and poor machining quality.In this paper，three kinds of grooved micro texture，which are parallel to the main cutting edge (PT)，vetical to the main cutting edge (VT) and lean 45° to the main cutting edge (LT)，are prepared through laser technology to the flank surface of the internal cooling twist drill.The drilling experiments of Ti6Al4V are carried out to study the drilling force，chip shape and the surface roughness of the machined hole，and compared with the non textured internal cooling twist drill (NT).The results show that the micro textured internal cooling twist drill can effectively reduce the drilling force.The drilling force of PT and VT twist drills is almost 23%~31% lower than that of NT twist drills，while that of LT twist drills is 46% lower than that of NT twist drills.For the chip shape，the micro textured twist drill can reduce the chip accumulation and increase the chip breaking performance，while the LT twist drill has almost no twining chips.For the surface quality of the processed hole，the micro textured twist drill can effectively reduce the Ra value.The Ra value of the LT twist drill reaches 1.28μm，which is about 54.4% lower than that of the NT twist drill，with the best comprehensive effect.

Keywords:micro texture；internal cooling twist drill；drilling force；surface roughness