Optimizing electrochemical micromachining parameters for Zr-based bulk metallic glass
Optimizing electrochemical micromachining parameters for Zr-based bulk metallic glass
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DOI：
10.1016/j.jmapro.2016.11.015
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发表时间：
2017-01-01
影响因子：
6.2
通讯作者：
Thorpe, S. J.
中科院分区：
文献类型：
--
作者：
Cole, K. M.;Kirk, D. W.;Thorpe, S. J.
块体金属玻璃（BMG）由于没有结晶特征而具有增强的机械和化学性能的独特组合，但其加工工艺仍在开发中。电化学微加工（ECMM）与微工具电极是一种很有前途的技术，微成形BMG没有使用高温或变形-这两者都可以诱导结晶。这项工作系统地研究了机制和处理参数负责材料表面的降解，允许开发一种新的协议，利用基于Zr的BMG的ECCM技术。Zr57Ni20Al15Cu5.5Nb2.5 BMG在2.94 M NaNO 3中的阳极极化和随后的显微镜检查显示，电化学微加工过程中的主要腐蚀机制是点蚀。通过计时电流法测定的再钝化电位为2.235 V。该电压用于防止电化学微加工过程中的自发再钝化。田口方法被用来评估电解质流速，占空比和脉冲电压范围的影响。信噪比和方差分析被用来优化电化学微加工过程中的ECMM参数。通过这种方法，电解液流量为0.4 Limin，占空比为1：10，电压范围为2.235-3 V，确定产生最佳孔的纵横比，表面粗糙度和速率的电化学微加工的Zr基BMG。(C)2016年制造工程师协会。由爱思唯尔有限公司出版。保留所有权利。
Bulk metallic glasses (BMGs) contain a unique combination of enhanced mechanical and chemical properties due to the absence of crystalline features, but their machining processes are still being developed. Electrochemical micromachining (ECMM) with microtool electrodes is a promising technique for microshaping BMGs without the use of elevated temperatures or deformation - both of which can induce crystallization. This work systematically studied the mechanisms and processing parameters responsible for degradation of the material surface allowing the development of a novel protocol for utilizing the ECCM technique for Zr based BMGs. Anodic polarization of Zr57Ni20Al15Cu5.5Nb2.5 BMGs in 2.94 M NaNO3 and subsequent microscopy revealed that the primary corrosion mechanism during electrochemical micro machining is pitting. Through chronoamperometry the repassivation potential was determined to be 2.235 V. This voltage was used to prevent spontaneous repassivation during electrochemical micromachining. The Taguchi method was used to assess the effect of electrolyte flow rate, duty cycle and pulsed voltage range. Signal-noise ratios and analysis of variance were used to optimize ECMM parameters of the electrochemical micromachining process. Through this method, an electrolyte flow rate of 0.4 Limin with a duty cycle of 1:10 and a voltage range of 2.235-3 V was determined to yield the optimal holes with respect to the aspect ratio, surface roughness and the rate of electrochemical micromachining of Zr-based BMGs. (C) 2016 The Society of Manufacturing Engineers. Published by Elsevier Ltd. All rights reserved.