Fabrication of Micro Diamond-Like Carbon-Nozzles by Plasma Oxidation Printing

Abstract

The plasma oxidation printing (POP) was proposed as a digital manufacturing to shape the diamond-like carbon (DLC) thick film into a micronozzle on the tool steel substrate. Its head shape was first designed by computer-aided design (CAD) and printed onto DLC film by the maskless lithography. The unprinted DLC was removed in depth by the anisotropic etching. Fine circular nozzle with the inner diameter of 10 μm and the height of 10 μm was fabricated during the duration time of 3.6 ks. Different from the micromilling or the micro-electric discharging, the micronozzle geometry is directly fabricated from its CAD data. The micronozzle with the cross-star outlet was constructed without the change of processing procedure and without use of tooling.

A DLC-Punch Array to Fabricate the Micro-Textured Aluminum Sheet for Boiling Heat Transfer Control

“…The alignment of micro-pillars was observed to have nearly the same clearance of 1.2–1.5 μm; homogeneous etching took place in the present plasma oxidation process. The etching rate was 8 μm/h, which is similar to etching rates recorded in other studies: 10 μm/h in [15] and 9 μm/h in [16]. …”

“…During the micro-embossing process, the tension was applied to this sheet to release the embossed sheet from the dies. As precisely stated in [14,15,16,17], the motion control has a significant influence on the transcription of the micro-texture onto aluminum sheets via the micro-embossing process. Pulse-wise motion with a maximum load of 150 kN and an incremental stroke of 15 kN was employed in the stroke control.…”

“…Both the applied load and the stroke of the upper die were monitored online via the load cell and the linear scale, respectively. After analyses in [16,17], the pulsewise motion was employed to control the loading and unloading processes in the following micro-embossing process.…”