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This paper aims to investigate the effect of centrifugal disk finishing (CDF) technique on the surface and subsurface characteristics of the fused deposited modeling (FDM) parts in both theoretical and experimental aspects. From theoretical aspect, a novel theoretical model is developed as a function of layer deposition orientation, layer thickness, finishing working time, density ratio and hardness ratio to estimate the surface roughness profile of FDM part at different finishing conditions and finishing time intervals. Meanwhile, from the experimental aspect, an experimental campaign was performed under different mechanical and mechanical-chemical finishing conditions to verify the theoretical model and also assess the surface and subsurface characteristics of the polished parts.

The theoretical model commences with an approximation of surface profile of the FDM part through a sequence of parabola arcs, continues with the calculation of reference line and machined surface profile and leads to a formulation of surface roughness of as-printed and polished surface. In the experimental section, the FDM parts are polished under dry, pure water, 25% and 50% volumetric aqueous acetone solutions finishing conditions through CDF technique.

The comparison between experimental and theoretical results reveals 9% mean absolute error between theoretical and experimental results. Meanwhile, Rq reduction percentage of polished parts under dry, pure water, 25% and 50% aqueous acetone solutions are 66.1%, 54.5%, 56.9% and 67.2%, respectively. The scanning electron microscopy results reveal severe layer damage in dry finishing condition, while the application of 50% aqueous acetone as a polishing solution completely eliminates layer damage. Another promising finding was sticky material phenomenon on the surface of polished part under 25% finishing condition. The Shore hardness test illustrates that the surface hardness improvement of the polished parts under dry, pure water, 25% and 50% aqueous acetone solutions finishing conditions are 8.4%, 2.25%, 4.36% and 10.8%, respectively. The results also revealed that the dimension variation of polished parts under dry, pure water, 25% and 50% aqueous acetone solutions are 0.634%, 0.525%, 0.545% and 0.608%, respectively. The edge profile radius of the as-printed part is 134 µm, while the edge profiles radius of the polished parts under dry, pure water, 25% aqueous acetone solution and 50% aqueous acetone solution are 785.5 µm, 545.5 µm, 623.5 µm and 721.5 µm, respectively, at the polishing time of 720 min.

This paper fulfills an identified need to study the benefits of the mechanical-chemical polishing technique in comparison to mechanical and chemical polishing strategy of the FDM parts for the first time. Beside the experimental campaign, the novel analytical formulation of surface roughness as a function of mechanical properties of abrasive media and FDM part and finishing specifications provides a valuable insight in the case of material-removal processes.

The purpose of this paper is to study the effect of doping, annealing temperature and visible optical excitation on CuO-ZnO nanocomposites’ acetone sensing properties and introduce an attractive candidate for acetone detection at about room temperature.

ZnO nanoparticles doped with CuO were prepared by sol-gel method, and the structure and morphology were characterized via X-ray diffraction, scanning electron microscope, energy dispersive spectroscopy and Brunauer-Emmett-Teller. The photoelectric responses of CuO-ZnO nanocomposites to cetone under the irradiation of visible light were investigated at about 30°C. The photoelectric response mechanism was also discussed with the model of double Schottky.

The doping of CuO enhanced performance of ZnO nanoparticles in terms of the photoelectric responses and the gas response and selectivity to acetone of ZnO nanoparticles, in addition, decreasing the operating temperature to about 30ºC. The optimum performance was obtained by 4.17% CuO-ZnO nanocomposites. Even at the operating temperature, about 30ºC, the response to 1,000 ppm acetone was significantly increased to 579.24 under the visible light irradiation.

The sensor fabricated by 4.17% CuO-ZnO nanocomposites exhibited excellent acetone-sensing characteristics at about 30ºC. It is promising to be applied in low power and miniature acetone gas sensors.

In the present research, a new nanocomposite material of CuO-ZnO was prepared by Sol-gel method. The optimum gas sensing properties to acetone were obtained by 4.17% CuO-ZnO nanocomposites at about 30ºC operating temperature when it was irradiated by visible light with the wavelength more than 420 nm.

This paper aims to successfully synthesize three-dimensional spindle-like Au functionalized Co₃O₄-ZnO nanocomposites; characterize the structure, morphology and surface chemical properties of the products; study the effect of Au NPs doping concentration, operating temperature different gas to, sensing properties; and introduce an attractive gas sensor for acetone detection.

Au NPs functionalized Co₃O₄-ZnO nanocomposite was prepared by coprecipitation and impregnation methods; the structure and surface chemical property of the products were characterized by XRD, SEM, TEM, UV-Vis, BET and XPS. The sensing ability of Au@Co₃O₄-ZnO for acetone and mechanism was analyzed systematically.

The results of gas sensing tests show that the unique component structure, Schottky junction and catalytic effect of Au functionalization make it have low operating temperature, excellent selectivity, high response (10 ppm, 56) and rapid response recovery time.

All the characterization and test data of the prepared materials are provided in this paper and reveals the gas sensing mechanism of the gas sensor.

The detection limit is 2.92–100 ppb acetone. It is promising to be applied in low-power, micro detection and miniature acetone gas sensors.

The gas sensor prepared has a lower working temperature and low detection limit, so it has promising application prospects in low-concentration acetone detection and early warning.

The unique component structure, Schottky junction and catalytic effect of Au functionalization Co₃O₄-ZnO make it have low operating temperature, excellent selectivity and rapid response recovery time.

This study aims to present the optimization of parameters and effects of annealing and vapor smoothing post-processing treatments on the surface roughness and tensile mechanical properties of fused deposition modeling (FDM) printed acrylonitrile butadiene styrene (ABS).

Full-factorial test matrices were designed to determine the most effective treatment parameters for post-processing. The parameters for annealing were temperature and time, whereas the parameters for the vapor smoothing were volume of acetone and time. Analysis of surface roughness and tensile test results determined influences of the levels of parameters to find an ideal balance between mechanical properties and roughness.

Optimal parameters for vapor smoothing and annealing were determined. Vapor smoothing resulted in significantly higher improvements to surface roughness than annealing. Both treatments generally resulted in decreased mechanical properties. Of all treatments tested, annealing at 100 °C for 60 min provided the greatest benefit to tensile properties and vapor smoothing with 20 mL of acetone for 15 min provided the greatest benefit to surface roughness while balancing effects on properties.

Vapor smoothing and annealing of FDM ABS have typically been studied independently for their effects on surface roughness and material properties, respectively, with varying materials and manufacturing methods. This study objectively compares the effects of each treatment on both characteristics simultaneously to recommend ideal treatments for maximizing the balance between the final quality and performance of FDM components. The significance of the input variables for each treatment have also been analyzed. These findings should provide value to end-users of 3D printed components seeking to balance these critical aspects of manufacturing.

Reports on the determination of rates of electropolishing of copper by measuring the limiting current of anodic dissolution of copper in phosphoric acid and in (water‐acetone) ‐phosphoric acid mixtures. Notes that the rate of electropolishing is decreased in (water‐acetone) ‐phosphoric acid mixtures and that the percentage inhibition of dissolution depends on the mole fraction of acetone, and its dielectric constant. Concludes with calculation of the thermodynamic parameters of activation.

The purpose of this paper is to investigate the effect of a sealing protective treatment on the water absorption and mechanical properties of acrylonitrile butadiene styrene (ABS)-printed parts by fused deposition modelling. Protective products include aqueous acetone solutions with different concentrations, polyurethane wood sealer and aqueous acrylic-based varnish.

Open porosity was estimated by the absorption coefficient and the total amount of water retained, obtained from water absorption tests. Mechanical characterization was performed by compressive and tensile tests. Different specimens with different build directions and raster angles were used.

The treatments with acetone solutions were not effective in reducing the porosity of ABS parts, as the amount of acetone that reduces effectively the porosity will also affect the sample dimensional stability. The polyurethane treatment was found to reduce the absorption coefficient, but the maximum water content and the open porosity remain almost unchanged in comparison with the ones obtained for untreated specimens. The treatment with an acrylic-based varnish was found to preserve the dimensional stability of the specimens, to reduce the open porosity and to maintain the compression and tension properties of the specimens in different build directions and raster angles.

Surface modification for water tight applications of ABS 3D printing parts enables new designs where both sealing and the preservation of mechanical properties are important. As per the knowledge of the authors, the water absorption and the mechanical behaviour of ABS 3D printed parts, before and after treatment, were not previously investigated.

The purpose of this paper is to show how a quartz crystal microbalance modified with poly (epichlorohydrin) (PECH) is fabricated and used for detection of acetone vapor using a spin‐coating method.

Measurements are based on the frequency shifts due to the adsorption of acetone vapor on the surface of the modified electrodes. A first‐order linear time‐invariant (LTI) system model is used to simulate the sensor response.

It is found that frequency shifts are linear to the concentrations of analyte, and cycle test examination shows good repeatability. The sensitivity to acetone vapor is better than other volatile compounds. A good match result is obtained with the LTI system model.

The device performance opens a potential way for analyzing acetone vapor.

The purpose of this research is to synthesize Al₂O₃-ZnO thick films, study the effect of doping and optical excitation on their sensing properties and introduce an attractive candidate for acetone detection in practice.

ZnO nanoparticles doped with Al₂O₃ were prepared by sol-gel method and characterized via X-ray diffraction and field-emission scanning electron microscopy. The sensing properties to acetone were investigated with an irradiation of UV. The sensing mechanism was also discussed with UV-Vis spectroscopy.

The doping of Al₂O₃ promoted the sensing response and stability of ZnO nanoparticles. The optimum performance was obtained by 4.96 Wt.% Al₂O₃-ZnO. The response to acetone (1,000 ppm) was significantly increased to 241.81, even just at an operating temperature of 64°C. It was also demonstrated that optical excitation with UV irradiation greatly enhanced the sensing response and the sensitivity can reach up to 305.14.

The sensor fabricated from 4.96 Wt.% Al₂O₃-ZnO exhibited excellent acetone-sensing characteristics. It is promising to be applied in low power and miniature acetone gas sensors.

In the present research, the optimum performance was obtained by 4.96 Wt.% Al₂O₃-ZnO at a low operating temperature of 64°C. The sensing properties were enhanced significantly with optical excitation, and the sensing mechanism was discussed with UV-Vis spectroscopy which has been reported rarely before.

This study aims to present that the chemo-responsive shape recovery of thermoplastic polyurethane (TPU) is tunable by solvents with different solubility parameters, and it is generic for chemo-responsive shape-memory polymer and its composites.

Two kinds of commercial TPU samples with different thicknesses were prepared by panel vulcanizer and injection molding (an industrial manner) to investigate their chemo-responsive shape memory properties in acetic ether and acetone.

Results showed that all of TPU films with different thicknesses can fully recover their original shapes weather they recover in acetic ether or acetone. But the recovery time of TPU films in acetone is greatly reduced, especially for the twisting samples. The residual strains of recovery TPU samples after extension reduce obviously.

The great decrement of recovery time is related to two factors. One is due to the bigger solubility parameter of acetone with higher dipole moment compared with those of acetic ether, and the other is the remained internal stress of TPU films after preparation. The internal stress is identified to have an effect on the shape-memory properties by comparing the recovery process of samples with/without annealing. The reduced residual strains of recovery TPU samples after extension is due to the increasing mobility of polymer segments after molecules of acetic ether penetrates into the polymeric chains.

This is a universal strategy to control the recovery process of shape-memory materials or composites. The underlying mechanism is generic and should be applicable to chemo-responsive shape-memory polymers or their composites.

This paper aims to measure exposures to airborne contaminants during three-dimensional (3-D) printing and post-processing tasks in an industrial workplace.

Contaminant concentrations were assessed using real-time particle number (0.007 to 1 µm) and total volatile organic compound (TVOC) monitors and thermal desorption tubes during various tasks at a manufacturing facility using fused deposition modeling (FDM^TM) 3-D printers. Personal exposures were measured for two workers using nanoparticle respiratory deposition samplers for metals and passive badges for specific VOCs.

Opening industrial-scale FDM^TM 3-D printer doors after printing, removing desktop FDM^TM 3-D printer covers during printing, acetone vapor polishing (AVP) and chloroform vapor polishing (CVP) tasks all resulted in transient increases in levels of submicrometer-scale particles and/or organic vapors, a portion of which enter the workers’ breathing zone, resulting in exposure. Personal exposure to quantifiable levels of metals in particles <300 nm were 0.02 mg/m³ for aluminum, chromium, copper, iron and titanium during FDM^TM printing. Personal exposures were 0.38 to 6.47 mg/m³ for acetone during AVP and 0.18 mg/m³ for chloroform during CVP.

Characterization of tasks provided insights on factors that influenced contaminant levels, and in turn exposures to various particles, metals < 300 nm and organic vapors. These concentration and exposure factors data are useful for identifying tasks and work processes to consider for implementation of new or improved control technologies to mitigate exposures in manufacturing facilities using FDM^TM 3-D printers.