DESIGN AND EVALUATION OF AN ULTRAHIGH SPEED MICRO-MACHINING SPINDLE
DESIGN AND EVALUATION OF AN ULTRAHIGH SPEED MICRO-MACHINING SPINDLE
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DOI：
10.1080/10910344.2010.489406
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发表时间：
2010-08
影响因子：
2.7
通讯作者：
Said Jahanmir;Zhaohui Ren;H. Heshmat;Michael J. Tomaszewski
中科院分区：
文献类型：
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作者：
Said Jahanmir;Zhaohui Ren;H. Heshmat;Michael J. Tomaszewski
一种新的高速微主轴已经开发用于微铣削，可以在接近500，000 rpm的转速下使用。由于传统的球轴承或流体润滑轴颈轴承不能在这样的速度下使用，新的微主轴使用一组轴颈和推力箔片轴承。在制造微主轴之前，对带有附加切削工具的转子进行转子动力学分析，确认转子在所需速度下是稳定的。然后使用收缩配合方法将切割工具附接到转子。将微主轴与三轴联动微铣床集成。使用125和300 μm立铣刀在大于300，000 rpm的速度下对铝合金进行切削实验。自由旋转和切削过程中的振动谱证实了微主轴的动态稳定性。振动谱由旋转频率主导，并且没有有害振动。在铝合金的微铣削中，将旋转速度增加到450，000 rpm允许进给速率增加到接近750 mm/min，从而将材料去除速率增加超过两个数量级。测量了几种不同进给速度下的直切削的尺寸精度。
A new ultrahigh speed micro-spindle has been developed for micro-milling that can be used at rotational speeds approaching 500,000 rpm. Since conventional ball bearings or fluid lubricated journal bearings cannot be used at such speeds, the new micro-spindle uses a set of journal and thrust foil bearings. Prior to fabrication of the micro-spindle, rotordynamic analysis of the rotor with an attached cutting tool confirmed that the rotor would be stable at the desired speeds. The cutting tool was then attached to the rotor using a shrink-fit approach. The micro-spindle was integrated with a 3-axis micro-milling machine. Cutting experiments were performed on an aluminum alloy at speeds greater than 300,000 rpm using 125 and 300 μm end-mills. Vibration spectra for free rotation and during cutting confirmed the dynamic stability of the micro-spindle. The vibration spectrum was dominated by the rotational frequency and was free of deleterious vibrations. The increase in rotational speed to 450,000 rpm in micro-milling of aluminum alloy allowed an increase in feed rate to nearly 750 mm/min, thus increasing the material removal rate by more than two orders of magnitude. The dimensional accuracy of several straight cuts made at different feed rates was measured.