Friction and cutting forces in cryogenic machining of Ti-6Al-4V
Friction and cutting forces in cryogenic machining of Ti-6Al-4V
复制标题
DOI：
10.1016/s0890-6955(01)00029-3
复制
发表时间：
2001-12-01
影响因子：
14
通讯作者：
Jeong, W
中科院分区：
文献类型：
--
作者：
Hong, SY;Ding, YH;Jeong, W
传统的切削液既作为冷却剂又作为润滑剂。在低温加工中，液氮（LN 2）由于其低温而被认为是一种有效的冷却剂;然而，其润滑性能并不为人所知。本研究的重点是研究如何切屑和刀具之间的摩擦力的影响，通过聚焦喷射液氮切削点加工Ti-6Al-4V。切削力测试结果表明，钛材料的冷强化提高了低温切削时的切削力，但较低的摩擦力降低了进给力。建立了一个数学模型，将斜切削三维力的测量值转化为刀具前刀面上的法向力和摩擦力分量，进而计算出有效摩擦系数。结果表明，在低温切削条件下，刀-屑界面的摩擦系数显著降低。切屑微观结构研究发现，剪切角增加和二次变形区厚度减小进一步证明摩擦力降低。(C)2001爱思唯尔科技有限公司版权所有。
Conventional cutting fluid serves both as a coolant and lubricant. In cryogenic machining, liquid nitrogen (LN2) is recognized as an effective coolant due to its low temperature; however, its lubrication properties are not well known. The focus of this study was to investigate how the friction between the chip and the tool is affected by focused jetting LN2 to the cutting point in machining Ti-6Al-4V. Results of cutting force measurements indicated that the cold strengthening of titanium material increased the cutting force in cryogenic machining, but lower friction reduced the feed force. A mathematical model was developed to convert the measured 3D forces in oblique cutting into the normal and frictional force components on the tool rake face, and then to calculate the effective friction coefficient. It was found that the friction coefficient on the tool-chip interface was considerably reduced in cryogenic machining. Increased shear angle and decreased thickness of the secondary deformation zone, findings from a chip microstructure study, offer further evidence that friction is reduced. (C) 2001 Elsevier Science Ltd. All rights reserved.