مهندسی مکانیک مدرس

مهندسی مکانیک مدرس

بهبود یکپارچگی سطح در میکرو کانال ایجاد شده در پلی‌دی‌متیل سیلوکسان توسط میکرو فرزکاری تخلیه الکترو‌شیمیایی

نوع مقاله : پژوهشی اصیل

نویسندگان
ارسلان ترابی 1
محمدرضا رازفر 2
1 گروه ساخت و تولید، دانشکده مهندسی مکانیک، دانشگاه صنعتی امیرکبیر، تهران
2 استاد، گروه ساخت و تولید، دانشکده مهندسی مکانیک، دانشگاه صنعتی امیرکبیر، تهران
چکیده
در سال‌های اخیر ایجاد ساختارهای سه‌بعدی و کانال‌های کوچک هدایت کننده جریان سیال، بر روی مواد نارسانای جریان الکتریکی نظیر پلی‌دی‌متیل سیلوکسان (PDMS)، جهت کاربرد در سیستم‌های الکترومکانیکی و پزشکی بسیار مورد توجه قرار گرفته است. عموما جهت ایجاد میکروکانال در پلی‌دی‌متیل سیلوکسان از فرایند لیتوگرافی استفاده می شود که از جمله محدودیت­های این فرایند می‌توان به زمان و هزینه بالای فرایند و دیواره‌های زاویه‌دار اشاره نمود. در تمامی مصارف، عملکرد کانال وابسته به کیفیت سطح آن است. در این پژوهش برای اولین بار فرآیند ماشین‌کاری تخلیه الکتروشیمیایی (ECDM) که با هزینه کم و نرخ براده برداری مناسب قادر به ایجاد کانال‌ بر روی مواد نارسانا است جهت ایجاد میکروکانال در پلی‌دی‌متیل سیلوکسان استفاده شده است. از سایر مزایای این روش می­توان به امکان دستیابی به عمق­های بالا اشاره کرد. بدین منظور تأثیر پارامترهایی فرایند نظیر غلظت الکترولیت، سرعت دورانی و پیشروی، اختلاف پتانسیل اعمالی بر کیفیت سطح و زبری سطح بررسی شد. ملاحظه شد که ماشین‌کاری تخلیه الکتروشیمیایی قادر است کانال­های با کیفیت سطح مشابه روش لیتوگرافی ایجاد کند. همچنین ملاحظه شد که با کاهش سرعت دورانی از 10000 دور بر دقیقه تا 0، زبری سطح 2 تا 4 برابر افزایش می­یابد این امر بدلیل افزایش ضخامت فیلم گاز و افزایش جرقه­های سرگردان از سطح ابزار و قطعه کار با کاهش سرعت دورانی رخ می­دهد. همچنین مقدار زبری سطح کانال ایجاد شده با افزایش ولتاژ از 38 به 42 ولت، به‌اندازه 36 درصد افزایش می‌یابد. غلظت الکترولیت 25% منجر به بهترین زبری سطح در تمام نمونه­ شد.
کلیدواژه‌ها
پلی دی متیل سیلوکسان
فرزکاری تخلیه الکتروشیمیایی
یکپارچگی سطح
میکرو کانال

موضوعات

عنوان مقاله English

Improvement of surface integrity of PDMS microchannel in the micro electrochemical discharge milling process

نویسندگان English

Arsalan Torabi 1
Mohammad Reza Razfar 2
1 Department of Mechanical Engineering, Amirkabir University of Technology, Tehran, Iran
2 Department of Mechanical Engineering, Amirkabir University of Technology, Tehran, Iran
چکیده English

In recent years, forming a 3D microfluidic channels on the electrical non-conductive material such as Polydimethylsiloxane (PDMS) in the micro-electromechanical system (MEMS) and medical applications is of great interest. Lithography is the most know process to create patterns on the PDMS however there are a few drawbacks to this process such as high operational cost and time, and sidewall angle. In all applications, the quality of the microchannel surface determines the performance of it. In this research as innovatively the electrochemical discharge milling (ECDM) which is known for lower operational cost and proper material removal rate (MRR) (i.e. process time), and is capable of creating patterns on electrical non-conductive material, was used to form a microchannel on the PDMS. To that end, the effect of process parameters such as electrolyte concentration, feed rate and cutting speed and voltage on the surface roughness and surface integrity deeply investigated. It was observed that ECDM is capable of creating patterns on the PDMS with surface integrity which is comparable with the lithography microchannel. It is also observed that decreasing the rotational speed from 10000 to 0 rpm results in increasing the surface roughness 2 to 4 times, this happens due to the increasing the thickness of the gas film around the tool, and subsequently increasing the flying sparks which results in higher surface roughness. Increasing the Voltage from 38 to 42 V results in 38% enhancement of surface roughness. The 25% electrolyte concentration results in lower surface roughness.

کلیدواژه‌ها English

Polydimethylsiloxane (PDMS)
Electrochemical discharge milling
Surface integrity
micro-channel
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مهندسی مکانیک مدرس
دوره 20، شماره 11
آبان 1399
صفحه 265-2615