钛合金铣削加工中冷却润滑方式的作用效果研究

Effects of Different Cooling and Lubrication Methods on Milling of Titanium Alloy

为了研究不同冷却润滑方式对钛合金铳削加工的影响,采用硬质合金刀具端面铳削方式在浇注式(WET)、干式(DRY)、微量润滑(MQL)、低温冷风(CA)及低温微量润滑(MQL-CA)条件下进行钛合金TC4切削试验,通过观测切屑颜色形态及测量切削力、表面粗糙度和刀具磨损衡量加工效果。结果表明,在金属去除率为1800mm3/min条件下进行连续26min的铳削加工后,MQL方式表面质量最好、表面质量稳定性最好、切削力最低、后刀面平均磨损长度及最大磨损长度均处于所有加工方式中的中间水平;CA方式表面质量最差、表面质量稳定性最差、切削力高于MQL及MQL-CA方式,低于DRY及WET方式,但其后刀面平均磨损量仅为0.008mm,最大磨损量为0.039mm,在所有加工方式中均为最小;MQL-CA方式表面质量及表面质量稳定性均处于5种方法的中间水平,切削力合力平均值仅高于MQL方式,低于其他方式。后刀面平均磨损长度为0.054mm,高于CA方式,略低于MQL方式。3种冷却润滑方式均优于传统浇注式切削及干切削,在钛合金铳削生产中可以推广应用,其中低温冷风切削更适用于粗加工,微量润滑切削更适用于精加工生产。

Some cutting experiments were carried out to investigate the influences of different cooling and lubrication methods on the milling process of titanium alloy with carbide tools.These experiments were conducted under the conditions of flood cutting(WET),dry cutting(DRY),minimum quantity lubrication(MQL),cooling air cutting(CA)and minimum quantity lubrication with cooling air(MQL-CA).The influences of different lubrication methods were evaluated by the following standards which included the shape and the color of chips,cutting forces,surface roughness and tool wear.The results showed that MQL obtained the lowest cutting force along with the best surface quality and the best surface quality stability but only a medixim tool wear among all the ways;CA cutting gathered higher cutting force with only a slight tool wear up to 0.008mm.The surface quality&surface quality stability of working piece were also the worst by this way.As far as MQL-CA cutting,all the key elements listed above were in the middle level.To summary,MQL was more suitable for finish machining.CA was better for rough machining and the three ways of cooling and lubrication were superior to the traditional flood cutting or dry cutting,and could be popularized and applied in the production of titanium alloy milling.