Effect of plastic side flow on surface roughness in micro-turning process
Effect of plastic side flow on surface roughness in micro-turning process
复制标题
DOI：
10.1016/j.ijmachtools.2005.11.014
复制
发表时间：
2006-11-01
影响因子：
14
通讯作者：
Melkote, Shreyes N.
中科院分区：
文献类型：
--
作者：
Liu, Kai;Melkote, Shreyes N.
在车削加工过程中，基于运动粗糙度的表面粗糙度预测通常会低估测量的表面粗糙度，特别是在小(微米级)进给速度下。还观察到微车削表面粗糙度随进给量的增加而减小，达到最小值后随进给量的进一步减少而增大。本文提出了一种微车削A15083-H116合金表面粗糙度的预测模型，该模型考虑了塑性侧向流动、刀具几何形状和工艺参数的影响。该模型结合了这些效应，并借助先前报道的基于应变梯度的有限元模型，更准确地估计了微米级变形下A15083-H116的平均流动应力。通过一系列微车削实验对表面粗糙度模型进行了评价。结果表明，该模型能较好地预测微车削加工的表面粗糙度。结果表明，微车削加工表面粗糙度理论值与实测值之间的偏差主要是由塑性侧向流动引起的表面粗糙度引起的。此外，研究还表明，在低进给条件下粗糙度的增加可以归因于刀具前方的应变梯度引起的材料强化引起的侧向流动的增加。(C)2005爱思唯尔有限公司。保留所有权利。
Kinematic roughness-based surface finish prediction is known to often under-predict the measured surface roughness in turning process, especially at small (micron level) feed rates. It has also been observed that the surface roughness in micro-turning decreases with feed, reaches a minimum, and then increases with further reduction in feed. This paper presents a model for predicting the surface roughness in micro-turning of A15083-H116 alloy that takes into account the effects of plastic side flow, tool geometry, and process parameters. The model combines these effects with more accurate estimation of the average flow stress of A15083-H116 at micron scale of deformation with the help of a previously reported strain gradient-based finite element model. The surface roughness model is evaluated through a series of micro-turning experiments. The results show that the model can predict the surface roughness in microturning quite well. It is shown that the commonly observed discrepancy between the theoretical and measured surface roughness in micro-turning is mainly due to surface roughening caused by plastic side flow. Further, it is shown that the increase in roughness at low feed can be attributed to the increased side flow caused by strain gradient-induced strengthening of the material directly ahead of the tool. (c) 2005 Elsevier Ltd. All rights reserved.