ABSTRACT

Nowadays, the extensive use of glass-based materials for biomedical, micro-fluidic, and MEMS applications grabbed great attention. The use of glass substrate for the above-said applications required subtractive processing to fabricate essential microstructures. Electrochemical discharge machining (ECDM) is an emerging hybrid micromachining process employed to machine the glass work-material. In ECDM, the thermal energy released by the tool electrode in the form of electrochemical discharges due to the electrical breakdown of hydrogen gas film takes away the material from the work surface. The thickness of hydrogen gas film plays a crucial role in deciding the discharge characteristics and subsequent thermal energy amount. Thus, in the present research work, an experimental investigation on hydrogen gas film thickness during the triplex hybrid process of rotary mode (RM) ECDM has been carried out. A high-speed imaging technique was utilized to capture the images of the gas film. These captured images were processed through Matlab’s edge detection toolbox to measure its thickness. Central composite design (CCD) of response surface methodology (RSM) was used to design the experimental plan. Applied voltage, tool rotation rate, and electrolyte concentration were taken as input parameters. To investigate the influence of gas film thickness on energy channelization behavior during RM-ECDM process, a material removal rate (MRR) and L/D ratio (diameter to depth ratio of machined holes) were taken as the response characteristics. A desirability approach was used to optimize the input parameters.

摘要

如今，玻璃基材料在生物医学、微流体和 MEMS 应用中的广泛使用引起了人们的极大关注。将玻璃基板用于上述应用需要减材加工来制造必要的微结构。电化学放电加工 (ECDM) 是一种新兴的混合微加工工艺，用于加工玻璃工件材料。在 ECDM 中，由于氢气膜的电击穿，工具电极以电化学放电的形式释放的热能将材料从工作表面带走。氢气膜的厚度在决定放电特性和随后的热能量方面起着至关重要的作用。因此，在目前的研究工作中，对旋转模式 (RM) ECDM 的三重混合工艺过程中的氢气膜厚度进行了实验研究。利用高速成像技术来捕捉气膜的图像。这些捕获的图像通过 Matlab 的边缘检测工具箱进行处理以测量其厚度。采用响应面法（RSM）的中心复合设计（CCD）设计实验方案。外加电压、工具转速和电解液浓度作为输入参数。为了研究气膜厚度对 RM-ECDM 过程中能量通道化行为的影响，以材料去除率 (MRR) 和 L/D 比（加工孔的直径与深度比）作为响应特征。合意性方法用于优化输入参数。