Optical Profilometer Research Articles

A COMPARATIVE STUDY ON THE PHOTORESIST PATTERNING OF GLASS AND SILICON WITH MICROHOLES VIA MASKLESS PHOTOLITHOGRAPHY

Maskless photolithography, a useful tool used in patterning the photoresist which acts as a mask prior to the actual etching process of substrate, has attracted attention mainly due to the taking advantage of reducing cost because of not requiring a preprepared mask and freedom in creating the desired pattern on any kind of substrate. In this study, we performed the positive photoresist patterning with microstructures on both glass and silicon substrates via maskless photolithography. Specifically, we examined the discrepancies between the transparent (glass) and reflective (silicon) substrates even though the photolithographic process has been carried out under the same conditions. Since the positive photoresist patterning was the subject of this study, we could successfully produce the microholes with almost circular shapes and properly placed in squarely packed on both substrates as confirmed by optical microscopy and profilometer mapping measurements. We observed additional rings around the holes when silicon was used as substrate while very clear microholes were obtained for glass. Besides, the number of the rings increased when the writing speed of laser (velocity) reduced. We claim that these important findings can be attributed to the standing wave effect phenomenon which results from the multiple reflections through the semi-transparent photoresist coated on the reflective surface of the polished silicon. In brief, we reveal an important conclusion, in this study, based on the differences in formation of the microholes only due to the substate preference while all the photolithographic process parameters are kept the same.

Investigation of electropolishing performance on surface residual stress and morphology of electrical discharge machined maraging steel

Electrical Discharge Machining (EDM)-machined maraging steel components are promising in the application field of aerospace and production tools. However, the unavoidable adverse effects of recast/white layer formation, high tensile residual stress, and micro-crack on the machined surface necessitate post-treatment techniques. The current study proposed Electropolishing (EP) as a post-treatment process to eliminate EDM’s adverse effects. The performance of EP on surface residual stress and morphology of ED machined surface was evaluated for an optimum combination of parameters, including applied voltage, polishing time, agitation, and temperature. Residual stress has been analyzed using the “sin2 ψ method” of X-ray Diffraction (XRD). After EDM, the generated surface residual stress was 407.17 MPa which had been relaxed to 35.27 MPa after EP. The surface morphology of maraging steel surfaces after EDM and EP were compared using an Atomic Force Microscope (AFM) and Field Emission Scanning Electron Microscope (FESEM). It is observed that micro-cracks, globules, voids, and thermal pitting marks were entirely eradicated following EP. It can also be seen that the EP has successfully removed the formed recast layer during EDM after 6 mins of polishing time. An average of 7.94 µm layer has been removed from the surface, removing all the surface defects. The optical profilometer analyzed the surface roughness profiles, and a 78% improvement in surface roughness was observed after EP.

Preliminary Assessment of Asymmetric Triangular Riblet Microstructures for Drag Deduction and Fouling Resistance: Numerical Modeling, Fabrication, and Performance Evaluation.

Several species of plants and animals demonstrate an ability to resist the accumulation of contaminants natural to their environments. To explain this phenomenon, mechanisms that facilitate fouling resistance have to be deciphered. Along these lines, this study is focused on the correlation between drag reduction and fouling resistance for underwater surfaces. This was accomplished by means of a novel microtopography inspired by fish-scales and conceived as a series of asymmetric triangular microgrooves oriented in the spanwise direction. A parametric study involving Large Eddy simulations was carried out to determine the most effective dimensions of the riblets and the results obtained have indicated a 9.1% drag reduction with respect to a flat reference surface. Following this, functional samples were fabricated in acrylic by means of a multi-axis micromachining center and diamond tooling. Surface quality and form accuracy of the fabricated samples were assessed with an optical microscope and optical profilometer. Finally, the fouling resistance of the samples was assessed by subjecting them to a flow of contaminated water. The results demonstrate that a relationship exists between the relative size of the particle and the fouling resistance of the microstructured surface.

Surface Roughness and Hardness of CAD/CAM Ceramic Materials after Polishing with a Multipurpose Polishing Kit: An In Vitro Study.

This article evaluates the effect of multipurpose polishing kit on surface roughness and hardness of three computer-aided design/computer-aided manufacturing (CAD/CAM) ceramic materials at different polishing durations. Weight changes of the polishing bur were also determined. Three CAD/CAM ceramic materials were lithium disilicate glass ceramic (IPS e.max CAD), translucent zirconia (VITA YZ), and zirconia-reinforced lithium disilicate ceramic (Celtra Duo). Ceramics were ground with a diamond bur, and polished with the multipurpose polishing kit (Eve Diacera HP), which comprises coarse and fine polishing burs. Surface roughness value (Ra) was measured using a noncontact optical profilometer (n = 10 per group) after grinding and every 15 seconds of coarse and fine polishing until 60 seconds. The complete polishing Ra was compared with the lab as-received specimens and human enamel. Surface morphology was examined using a scanning electron microscope after 60-second coarse and fine polishing and compared with the lab as-received specimens. Hardness was measured using a Vickers hardness tester on the lab as-received specimens and after the final polishing process (n = 4 per group). Changes in surface roughness and polishing bur weight of each material were analyzed using one-way repeated-measures analysis of variance (ANOVA) and dependent t-test. One-way ANOVA was used to detect differences in surface roughness, Vickers hardness, and bur weight among materials within the same polishing duration (α = 0.05). From grinding to complete polishing, the greatest Ra reduction was found in VITA YZ, followed by Celtra Duo and IPS e.max CAD. Final Ra values of all ceramics after 60-second fine polishing were not significantly different, and were similar to that of enamel and lab as-received specimens. Vickers hardness of ceramic materials did not change after grinding and polishing. Coarse polishing bur demonstrated the highest weight loss after polishing VITA YZ, followed by Celtra Duo and IPS e.max CAD. The multipurpose polishing kit reduced surface roughness of CAD/CAM ceramic materials to the similar level of the lab as-received specimen and enamel regardless of material's hardness. The reductions of surface roughness and a coarse polishing bur weight were highest in VITA YZ, followed by Celtra Duo and IPS e.max CAD.

Hybridized-flow flame spray (HFFS) process for the development of superior ceramic coatings

The present study deals with a novel, effective and single step thermal spray coating process development. The process is named as ‘Hybridized-Flow Flame Spray (HFFS) process’. The process is very much suitable for the development of ceramic coatings with superior properties when compared to conventional Powder Flame Spray (PFS) coatings. The HFFS process is capable in addressing the shortcomings (porosity, density, hardness, surface quality) of PFS coatings. The physical, mechanical and metallurgical analysis of PFS and HFFS coatings are done using density measurement kit, 3-D optical profilometer, Vickers and scratch hardness, and scanning electron microscope (SEM). The results show significant improvement in the properties. The increment in density (≈24%), hardness (Vickers ≈ 37% and scratch ≈ 126%); and decrement in coating thickness (≈35%) and average surface roughness (≈47%) of HFFS sprayed coatings are observed. The results are benchmarked with those of PFS coatings. The improved responses are attributed to the densification of coating structure and improved microstructural changes due to the presence of hybridized flow in the HFFS.

Stability and Failure Analysis of a W-Based Microhotplate

In this paper, we present the stability and failure of a tungsten-based microhotplate (W-MHP) fabricated with 0.5- <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu \text{m}$ </tex-math></inline-formula> standard CMOS technology. Resistance measurements and three-dimensional optical profilometer results combined with scanning electron microscopy observations were used to analyze the failure mechanisms of the W-MHP at operation temperatures up to 1000 °C. The electro-stress migration of the W film, recrystallization of the polycrystal W thin film, and breakage of the dielectric membrane were the dominant stability-failure mechanisms observed. The W-MHP had recoverable deformation and no evident resistance drift when the working temperature was below 450 °C. Correspondingly, at the operating temperature range of 500 °C– <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$850~^{\circ }\text{C}$ </tex-math></inline-formula> , the W-MHP showed unrecoverable deformation and regular resistance drift caused by the electro-stress migration of the W heater and the interdiffusion of atoms between the W, Ti/TiN and SiO2. At temperatures higher than <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$1000~^{\circ }\text{C}$ </tex-math></inline-formula> , the recrystallization of the polycrystalline W film caused a sharp drop in resistance. In addition, sudden and large heat pulses were more likely to cause the suspended membrane to rupture, which resulted from the rapid accumulation of internal thermal stress and lack of time to release, indicating that the operating temperature of the MHP should slowly increase or decrease. One million cycles of thermal pulse between <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$25~^{\circ }\text{C}$ </tex-math></inline-formula> and 300 °C did not cause performance degradation of the device. Self-heating high-temperature rapid thermal annealing significantly improved the high-temperature stability of the MHP. [2022-0135]

INFLUENCE OF PRE-HARDENED GX120Mn13 CAST STEEL ON THE TRIBOLOGICAL PROPERTIES UNDER TECHNICALLY DRY FRICTION

This paper presents the results of tribological tests on high manganese GX120Mn13 cast steel under technically dry friction conditions. The tests were carried out using a TRB3 ball-on-disc tribometer using a 6mm-diameter SiC ball as a counter-sample for a specimen made of GX120Mn13 cast steel containing a localised prehardening area on the test surface with a hardness of approximately 597 HV10 (the non-hardened area had a hardness of approximately 325-364 HV10). During the test, the ball travelled in a 16.68 mm diameter circle and passed through both hardening and non-hardened areas. The resulting erosion marks were assessed using an optical profilometer and scanning microscope tests, which showed that the maximum depth of erosion in the previously hardening area was 0.77 μm and was more than twice as deep as in the non-hardened areas surveyed. In contrast, the area of attrition was twice as small as in the non-hardened area located in the axis of the previously applied load and more than three times smaller, but in the area located on the side of the axis and 8.34 mm away from it. Thus, from the point of view of the abrasion resistance of GX120Mn13 cast steel, the validity of its prior hardening before the operation was confirmed.

Experimental and theoretical analyses of material removal in poppet valve magnetorheological finishing

Poppet valves used in internal combustion engines have a high risk of failure due to significant temperature and pressure. These poppet valves need surface finishing at the nano-scale level to prolong their life during their working use. In the present research, the chosen poppet valve has narrow ridge profiles, which is difficult to nano-finish by conventional processes due to certain limitations. The magnetorheological fluid-based finishing method can be effectively used for this kind of complicated narrow profile. For the magnetorheological fluid-based finishing processing of the poppet valve, a novel magnet fixture and setup is used. For checking the efficiency of this setup, surface characterization and surface roughness for polished and unpolished surfaces are outlined using a field-emission scanning electron microscope, microscope and optical profilometer. The final surface roughness of Sa = 23.1 nm at poppet profiles were obtained. All manufacturing defects like burrs, dents, scratches and pits are almost removed. The study of finishing forces in the magnetorheological fluid-based finishing method is also carried out using magnetostatic fluid–solid interaction, experimental and theoretical analysis. This force analysis supports the development of the material dislodgement model to anticipate material removal rate while finishing. The gap (error = 12.87%) between the experimental and theoretical material removal rate is marginal. It has high accuracy and reliability for specific applications.

Material removal analysis during MR polishing of complex gear teeth profiles

The geometric intricacy of tiny gears makes nano-finishing difficult. In the current study, the magnetorheological (MR) polishing process is used for the nano-finishing of intricate surfaces of tiny gear components uniformly. For polishing, the technique employs a dynamic fluid recognized as magnetorheological polishing fluid (MRPF), that has the ability to stiffen in the presence of a magnetic field. Base media, iron and abrasive particles are utilized to synthesize the MRPF. Permanent magnets produce the necessary magnetic field in the finishing zone. Finite element analysis (FEA) is utilized to model the iron and abrasive particles to understand better how they would react in the external magnetic field. FEA is utilized to analyze the magnetic flux density (MFD) distributions and the amount of magnetic force exerting on gear profiles through iron particles (IPs). It has been observed that the IPs present close to the active abrasives are primarily accountable for indenting active abrasives into the workpiece surfaces. In addition, the influence of particle dimension on the stiffness of iron particle chains in MRPF has been investigated. A mathematical model for material removal is developed by utilizing normal finishing force analysis on active abrasives. Lastly, the finishing surface characteristics of gear profiles are examined using an optical profilometer, field emission scanning electron microscope (FESEM) and spectroscopic analysis. Finally, 92.68% improvement in the surface finish is observed.

An efficient surface profile measurement with the scanning path based on Hilbert and Gosper fractal curves

This paper proposes a non-contact efficient measurement method of surface morphology with the scanning path based on the Hilbert and Gosper fractal curves. By comparing the proposed two types of fractals scanning curves with the traditional reciprocating S-curves, it can be found that the plane distribution of measuring points of the fractal curves is much more uniform, and then the measurement performance is much improved. The two fractal curves with different iterative times are introduced as a measurement path of the surface morphology, and the local three-dimensional roughness and overall shape tolerances of the parts are determined. In the view of the measurement point uniformity, different total number of fractals of iterations are compared as the measurement path of the surface morphology. In order to verify the accuracy of the proposed method, a specialized measuring device is developed, and measurement verification is made with the optical profilometer.

INFLUENCE OF BLOOD CONTAMINATION ON SURFACE CHANGES OF MINERAL TRIOXIDE AGGREGATE AND BIODENTINE

The biological environment is crucial for the bioactivity of modern calcium-silicate cements. Most of the studies of the materials were performed under ideal conditions, which are difficult to achieve in clinical practice. The aim of this study was to evaluate the surface characteristics of MTA+ (PPH Cerkamed, Medical company, Polish) and Biodentine in PBS and blood environments with a non-contact 3D optical profilometer Materials and methods: Retrograde cavities were prepared on the root surfaces of freshly extracted teeth. The cavities were filled with MTA+ or Biodentine, and the samples were immersed in PBS or Blood and placed in an incubator for 28 days. The surface of each specimen was scanned using a 3D optical profilometer at three different time points (1, 3, and 28 days). Statistical calculations were carried out using IBM SPSS Statistics (v.25), and significance was fixed at p &lt;0.05. Results: Both materials showed that blood contamination affects the roughness of their surface. Both materials placed in blood contaminated conditions show reduced and constant roughness during the reported time periods (p&gt; 0.05). This study showed that the surface roughness of MTA+ and Biodentine was adversely affected by blood pollution.

Researches on the geometrical and dimensional accuracy for complex thin parts made of electrical steel by abrasive waterjet machining

The electrical steel laminations which compose the rotor and stator core for electrical motors have complex 2D shapes. When these parts require small batches of production, they can be efficiently manufactured only by flexible methods. The paper presents the results of using abrasive waterjet machining (AWJ) to obtain such parts within the frame of a research project with EU funding. The main objective of the research was the analysis of geometrical and dimensional accuracy of the parts which will confirm that AWJ is a suitable process in this case. The parts were measured on an optical digital profilometer. The measurement process was not simple because the parts are relatively large and cannot be focused only by one shot by the camera. Also, another important issue were the profile edges inconsistencies due to the burrs. Those problems and the limitations of the measurement technology did not allow the automation of measurement. The results and discussions proved that AWJ can be used successfully for manufacturing such parts and the machining process is traceable.

Surface tempering of poly-(3 thiophene acetic acid) coated carbon fiber paper electrode with spine-like cobalt inorganic phosphate: An efficacious electrochemical metol sensor

N-methyl-p-aminophenol sulfate (metol) is a photographic developing agent that has a toxic effect on humans and aquatic life. A cost-effective and sensitive electrochemical sensor was developed by electrodepositing Co-Pi over poly-(3 thiophene acetic acid) coated carbon fiber paper electrode (Co-Pi/PTAA/CFP) for the determination of metol (ML). Surface modification of Co-Pi facilitates superior electrocatalytic performance by offering more active sites and faster electron transport kinetics. The Physico-chemical characterization of the fabricated electrode was carried out by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) Field emission scanning electron microscopy (FESEM) with energy-dispersive X-ray spectroscopy (EDS), Optical profilometer, Fourier transform infrared spectroscopy (FTIR), and electroanalytical techniques. The electrochemical studies were performed using Cyclic voltammetry (CV), Electron Impedance spectroscopy (EIS), and Differential pulse voltammetric (DPV). DPV studies revealed excellent sensing performance for ML, with a wide linear dynamic range of 6 nM to 800 nM, and a limit of detection (LOD) of 2 nM. A distinctive oxidative anodic peak was observed at 0.11 V indicating the excellent electrochemical performance of the electrode. The results suggested that the developed electrode exhibited good catalytic activity, selectivity, and sensitivity towards the electrochemical determination of ML. Further, the developed electrode was extended to its application in real samples obtained from lake water and domestic wastewater.

Comparison of Different Finishing and Polishing Systems on Surface Roughness and Bacterial Adhesion of Resin Composite.

Insufficient dental restoration finishing and polishing may lead to plaque accumulation, gingival inflammation, staining, caries, and esthetic impairment. Here, the effect of two finishing and polishing systems on surface roughness and bacterial adhesion were evaluated. Two finishing and polishing kits were evaluated: diamond burs (Shine 1-2, Strauss & Co, Raanana, Israel) and paper discs (Sof-Lex 3M ESPE, Seefeld, Germany) (n = 30 each). For each group surface roughness was evaluated using an optical profilometer (Contour GT-K1, Bruker, Billerica, MA, USA) (n = 10). Surface bacteria were evaluated for biofilm biomass using crystal violet (CV) staining (absorbance measured at 538 nm) and viable counts (CFU/mL) (n = 20). The control group included polymerized discs against a Mylar strip (n = 30). Student's t test and one-way ANOVA were used for statistical evaluation. Diamond burs, paper discs, and control average surface RA were 169.4 ± 45.2 µ, 364 ± 77.7 µ, and 121.2 ± 18.1 µ, respectively. There was a significant difference found between all groups (p &lt; 0.00001). Bacterial biomass on diamond burs, paper discs, and control samples were 0.458 ± 0.161, 0.507 ± 0.139, and 0.446 ± 0.142, respectively (p = 0.257). Viable bacterial counts (CFU/mL) on diamond burs, paper discs, and control samples were 2.25 × 104, 2.95 × 104, and 2.75 × 104, respectively (p = 0.856). A comparison between two finishing and polishing kits showed that the shine 1-2 diamond bur kit produced a smoother surface than the polishing disc kit. No differences were found in the biofilm biomass quantification and bacterial viable count between the groups.

Improvement of partial discharge resistance of polypropylene under AC voltage by blending elastomer

This paper reports on the partial discharge (PD) erosion characteristics of polypropylene (PP)/elastomer blends where ethylene-octene copolymer elastomer (EOC) and propylene-based elastomer are involved. The PD erosion is performed through a pair of needle-to-plane electrodes by applying 5 kV AC voltage for 2 h. A high-frequency current transformer, optical recorder, and ozone sensor are used to capture the information released during the PD erosion process. In addition, a 3D optical profilometer is employed to record the erosion profile, from which the erosion depth and the surface roughness can be extracted. Carrier trap distribution is derived from the isothermal surface potential decay measurement. The influences of elastomer type and content on the PD resistance are analyzed. The results show that the resistance is improved with the addition of elastomer, and the blend containing EOC of 20 wt% has the best PD resistance among all samples, which is 61.9% higher than that of the pure PP. It is proposed that the carrier trap characteristics, the property of elastomer, and the free volume in the material play important roles in the improvement of the PD resistance. This work provides a potential method to enhance the PD resistance of PP by blending elastomer with proper type and content.

The effect of worked material hardness on stone tool wear.

The identification of ancient worked materials is one of the fundamental goals of lithic use wear analysis and one of the most important parts of understanding how stone tools were used in the past. Given the documented overlaps in wear patterns generated by different materials, it is imperative to understand how individual materials’ mechanical properties might influence wear formation. Because isolating physical parameters and measuring their change is necessary for such an endeavor, controlled (rather than replicative) experiments combined with objective measurements of surface topography are necessary to better grasp how surface modifications formed on stone tools. Therefore, we used a tribometer to wear natural flint surfaces against five materials (bone, antler, beech wood, spruce wood, and ivory) under the same force, and speed, over one, three, and five hours. The study aimed to test if there is a correlation between surface modifications and the hardness of the worked material. We measured each raw material’s hardness using a nano-indentation test, and we compared the surface texture of the flint bits using a 3D optical profilometer. The interfacial detritus powder was analyzed with a scanning electron microscope to look for abraded flint particles. We demonstrate that, contrary to expectation, softer materials, such as wood, create a smoother surface than hard ones, such as ivory.

Effects of nanofiller and voltage stabilizer on partial discharge resistance of polypropylene/elastomer blends: A comparison study

AbstractThis paper reports on the individual and synergistic influence mechanisms of nano‐silica (SiO2) and voltage stabilizers on partial discharge (PD) resistance of polypropylene blended with ethylene‐octene copolymer elastomer. The SiO2 nanoparticles and three types of voltage stabilizers, that is, benzoin, 4,4′‐dimethoxybenzil, and 3‐aminobenzoic acid are selected as fillers to prepare samples. PD is initiated in a rod‐to‐plane electrode system with an alternating current voltage of 5 kVrms. PD characteristics are captured with multi‐sensors, and the erosion profile of the test sample is measured using a three‐dimensional (3D) optical profilometer. Carrier trap distribution is extracted with isothermal surface potential decay measurement to assist the analysis of PD eroding material. Fourier transform infrared spectrum, scanning electron microscopy, X‐ray diffraction spectrum, and differential scanning calorimetry analysis are performed to reveal the change in material structures caused by the fillers. Test results indicate that the PD resistance of the blend can be improved by the addition of nano‐SiO2 and voltage stabilizers individually and synergistically. The PD resistance of PO is increased by 71.2% at most in the sample with 3 wt% nano‐SiO2 addition. The sample filled with SiO2 exhibits better PD resistance than that with the voltage stabilizer or co‐added, which should be ascribed to the introduction of deep traps, the formation of the packaged layer, the suppression of oxygen diffusion of the nanofillers, and the good compatibility between additives and the polymer matrix.

Anchored ferrocene based heterogeneous electrocatalyst for the synthesis of benzimidazoles

A facile and sustainable electrochemical synthetic strategy for phenyl benzimidazoles has been developed using a ferrocene-based electrocatalyst anchored on Toray carbon paper (TCP) coated with conducting polymeric film. The developed electrode was used for the electrochemical dehydrogenative cyclization reaction of o-phenylene diamine and benzaldehyde using lithium perchlorate/acetonitrile as electrolyte. The surface characteristic properties of the developed electrode were characterized by FESEM, Optical profilometer and X-ray photoelectron spectroscopy. Electron transfer mechanism of the anchored ferrocene-based electrocatalyst was thoroughly studied. To determine the efficacy of the catalyst, the electron transfer coefficient (0.5) and apparent rate constant 41.4 s−1 were determined. The cyclic voltammetry studies reveal that the electrochemical oxidation peak for the synthesis of benzimidazole occurs at 0.48 V. The formation of the product was confirmed by Gas chromatography and Nuclear Magnetic Resonance spectroscopy. A comparison chart is presented for the green metrics and sustainability of the present strategy with other electrochemical approach.

Изготовление и исследование низкоплотных металлических материалов

For experiments on laser interaction with matter, a method has been developed for manufacturing a low-density material from aluminum and copper by the method of resistive sputtering in an inert gas – argon. Deposition was carried out at two gas pressures: 40 Pa and 440 Pa. The densities of the obtained samples were determined by the gravimetric method: the mass of the sprayed layer was measured by weighing the substrate before and after deposition, the volume was calculated based on measurements of the material thickness using an optical profilometer. The thickness of the deposition layer is 74.8 ± 0.9 μm. The minimum density was achieved on a sample of a porous aluminum layer obtained at a pressure of 440 Pa. Its value was (72 ± 4) mg/cm3. According to the images obtained with a scanning electron microscope, it was found that the pore size in the material does not exceed 3 microns. Measurements of the chemical composition with an X-ray fluorescence spectrometer showed the presence of oxygen on the samples, which indicates the oxidation of the surface layer of the prepared samples. targets (2 pcs.) for experiments on laser interaction with matter were made from the samples of porous aluminum obtained in this work.

Effect of process parameters on surface roughness, dimensional accuracy and flatness of VeroBlue RGD840 rigid opaque materials

Abstract In the present scenario, additive manufacturing is considered to produce the functional parts in low volume. This investigation deals with the effect of process parameters viz., raster angle, orientation and type of surface on dimensional accuracy, flatness, shrinkage and surface roughness of VeroBlue RGD840 rigid opaque materials, produced by the polyjet process. A Taguchi array (L 8) is used to design the experiment. Surface roughness parameters are measured by using an optical profilometer. Dimensional accuracy and flatness are measured by using coordinate measuring machines. Analysis of variance is employed to evaluate the effect of individual process parameters. An empirical model is developed to predict the dimensional accuracy, flatness and surface roughness. Results revealed that the optimum level of process parameters are different for the dimensional accuracy and flatness. A multi-objective optimization technique is employed to get the best level of process parameters. The belt level of process parameters are raster angle of 60°, orientation flat and glossy type of surface finish. The best value of surface roughness R a = 28 nm, percentage error in dimensional accuracy of 12.13 and flatness of 0.0503 mm are observed. Confirmation tests are performed at the best level of process parameters to verify the results.