The Effect of the Rolling Direction, Temperature, and Etching Time on the Photochemical Machining of Monel 400 Microchannels

Abstract

The present paper describes the effect of the rolling direction on the quality of microchannels manufactured using photochemical machining (PCM) of Monel 400. Experiments were carried out to fabricate microchannels along and across the rolling direction to investigate the effect of the grain orientation on microchannel etching. The input parameters considered were channel width and rolling direction, whereas the depth of etch was the response parameters. Different channels of widths of 60, 100, 150, 200, and 250 μm were etched. The effects of the etching time and temperature of the etchant solution on the undercut and depth of the microchannels were studied. For good quality microchannels, the effects of spinning time, spinning speed, exposure time, and photoresist film strength were also taken into consideration. Optimized values of the above were used for the experimentation. The results show that the depth of etch of the microchannel increases more along the rolling direction than across the rolling direction. The channel width and depth are significantly affected by the etching time and temperature. The proposed study reports an improvement in the quality of microchannels produced using PCM.

Milling Microchannels in Monel 400 Alloy by Wire EDM: An Experimental Analysis

“…Among these processes, WEDM has higher machining efficiency and could provide higher flexibility in machining regular and complex shapes and profiles with high precision for microfeatures, especially for conductive materials [7]. Additionally, it is worth mentioning that, as compared to the laser machining and photochemical machining, the WEDM process has a higher capacity to control the shape of the microchannels, because the laser produces tapered channels as demonstrated by Ahmed et al [8] and has deep detrimental impact [9], whereas, Micromachines 2020, 11, 469 2 of 17 the photochemical machining produces channels with undercuts as shown by Patil and Mudigonda [5]. In addition, the photochemical process is a slower process, not environmentally safe and can only be applied for mass production.…”

“…Generally, in nickel-base alloys, the machining of such alloys is hardly carried out in conventional machining processes, especially in the case of machining microfeatures, due to their superior mechanical properties in addition to the lower thermal conductivity, high heat capacity and high chemical reactivity to most tool materials [3,4]. High tooling wear, poor surface quality, and poor machinability are obvious drawbacks of conventional micromilling and consequently restrict the process for precise microfeaturing [5,6]. These issues could be overcome using non-traditional machining processes such as laser beam machining (LBM), photochemical machining (PCM), abrasive water jet machining (AWJM) and wire electrical discharge machining (WEDM).…”

Investigation on Surface Roughness of Inconel 718 in Photochemical Machining

“…Saraf and Sadaiah studied effect of magnetic field on the etch rate of SS316L [5]. Patil and Mudigonda conducted experiments on Inconel 718 for understanding the effects of control variables such as speed of cutting, rate of feed, and depth of cut on surface finish and residual stresses at different level of parameters [6]. Qu et al carried out the study on Monel 400 using PCM.…”

Chemical Machining of Monel

“…Therefore, Monel 400 is chosen for this study. Generally, micromachining, laser machining, dry machining and wet chemical machining have been used for fabrication of microchannel [2][3][4][5][6].…”