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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 investigate the effects of abrasive contents, oxidizer contents, slurry flow rate and polishing time in achieving a mirror-like finish on polished surfaces. Chemical mechanical polishing (CMP) is now widely used in the aerospace industry for global planarization of large, high value-added components.

Optimal parameters are applied in experimental trials performed to investigate the effects of abrasive contents, oxidizer contents, slurry flow rate and polishing time in achieving a mirror-like finish on polished surfaces. Taguchi design experiments are performed to optimize the parameters of CMP performed in steel specimens.

Their optimization parameters were found out; the surface scratch, polishing fog and remaining particles were reduced; and the flatness of the steel substrate was guaranteed. The average roughness (Ra) of the surface was reduced to 6.7 nm under the following process parameters: abrasive content of 2 weight per cent, oxidizer content of 2 weight per cent, slurry flow rate of 100 ml/min and polishing time of 20 min.

To meet the final process requirements, the CMP process must provide a good planarity, precise selectivity and a defect-free surface. Surface planarization of components used to fabricate aerospace devices is achieved by CMP process, which enables global planarization by combining chemical and mechanical interactions.

Chemical mechanical polishing (CMP) has attracted much attention recently because of its importance as a nano-scale finishing process for high value-added large components that are used in the aerospace industry. The paper aims to discuss these issues.

The characteristics of aluminum nanoparticles slurry including oxidizer, oxidizer contents, abrasive contents, slurry flow rate, and polishing time on aluminum nanoparticles CMP performance, including material removal amount and surface morphology were studied.

Experimental results indicate that the CMP performance depends strongly on the oxidizer, oxidizer contents, and abrasive contents. Surface polished by slurries that contain nano-Al abrasives had a lower surface average roughness (Ra), lower topographical variations and less scratching. The material removal amount and the Ra were 124 and 7.61 nm with appropriate values of the process parameters of the oxidizer, oxidizer content, abrasive content, slurry flow rate and polishing time which were H₂O₂, 2 wt.%, 1 wt.%, 10 ml/min, 5 min, respectively.

Based on SEM determinations of the process parameters for the polishing of the surfaces, the CMP mechanism was deduced preliminarily.

This paper aims to review recent advances and applications of abrasive processes for microelectronics fabrications.

More than 80 patents and journal and conference articles published recently are reviewed. The topics covered are chemical mechanical polishing (CMP) for semiconductor devices, key/additional process conditions for CMP, and polishing and grinding for microelectronics fabrications and fan-out wafer level packages (FOWLPs).

Many reviewed articles reported advanced CMP for semiconductor device fabrications and innovative research studies on CMP slurry and abrasives. The surface finish, sub-surface damage and the strength of wafers are important issues. The defects on wafer surfaces induced by grinding/polishing would affect the stability of diced ultra-thin chips. Fracture strengths of wafers are dependent on the damage structure induced during dicing or grinding. Different thinning processes can reduce or enhance the fracture strength of wafers. In the FOWLP technology, grinding or CMP is conducted at several key steps. Challenges come from back-grinding and the wafer warpage. As the Si chips of the over-molded FOWLPs are very thin, wafer grinding becomes critical. The strength of the FOWLPs is significantly affected by grinding.

This paper attempts to provide an introduction to recent developments and the trends in abrasive processes for microelectronics manufacturing. With the references provided, readers may explore more deeply by reading the original articles. Original suggestions for future research work are also provided.

This study aims to clarify the influence mechanism of polishing solution type on the glazing evolution of fixed abrasive pad under different interfacial pressure conditions.

The tribological experiments were carried out on the friction and wear machinery with W3-5 diamond fixed abrasive pad and quartz glass workpiece under three polishing solution types of five pressure conditions. The changes of surface morphology, porosity and hardness of fixed abrasive pad were detected by white light interferometer, optical microscope and shore hardness tester.

The results showed that the glazed phenomenon of fixed abrasive pad is occurred after a certain time, which is more obvious with the increasing of interfacial pressures. The polishing solution type has a significant effect on the glazing time, although the glazed phenomenon is inevitable. The mechanism of it is that the micro-convex peaks on the surface of the fixed abrasive pad are easily wear, and the pores are blocked by the accumulation of waste debris generated during the experiment process. Thus, a smooth and high-density hard layer is formed on the surface of the fixed abrasive pad which induces the decreasing of the friction coefficient and surface roughness value. For selected polishing solution types, the wear rate of micro-convex peaks is different due to the corrosion action difference with polishing pad surface.

The main contribution of this work is to provide a new investigating method for further understanding the glazing evolution mechanism of fixed abrasive pad.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-08-2023-0257/

This paper aims to study the effects of the different processing parameters in the reciprocating magnetorheological polishing (RMRP) on the surface roughness (Ra) and material removal rate (MRR) of the workpiece surface.

The principle of RMRP method is discussed, and a series of the single factor experiments are performed to evaluate the effects of the workpiece’s rotational speed, the reciprocating frequency, the magnetic field strength, the working gap and the processing time on machining results using the RMRP device.

The RMRP method is effective and practical for K9 glass polishing, and the optimized processing parameters are obtained by the single factor experiments of RMRP. The surface roughness of the workpiece is reduced from 332 nm to 28 nm under optimized processing parameters.

In the present study, the RMRP method is proposed, and a system of experiments is carried out using the RMRP device. The RMRP device can improve the surface roughness and MRR of the K9 glass significantly. Furthermore, the test results provide references for reasonable selection of the processing parameters in magnetorheological polishing process.

This paper aims to analyze the significance of machining parameters (workpiece’s rotational speed, magnet coil current and working gap) on final Ra (surface roughness) and material removal rate (MRR) of workpiece in reciprocating magnetorheological polishing (RMRP) process.

The research is planned to analyze, model and predict the optimum machining parameters to anticipate final Ra and MRR by applying response surface methodology (RSM) and multiresponse optimization (desirability function approach). The experiments have been planned by design of experiments (DOE). Analysis of variance (ANOVA) is applied to determine the significances of machining parameters on RMRP performance characteristics.

Response surface plots for final Ra and MRR by RSM show that machining parameters are significant for the responses. The optimum machining parameters obtained are optimized by desirability function approach (DFA), and the optimum parametric combination has been validated by confirmatory experiments. The experimental results of the final Ra and MRR are deviated by 5.12% and 2.31% from the response results under the same optimization conditions, respectively.

In this study, the RMRP responses (final Ra and MRR) are improved at predicted input machining parameters condition obtained by RSM and DFA approach. Furthermore, the research results provide a reference for experimental design and optimization of MRP process.

This paper aims to study the influence of the different parameters of magnetorheological polishing fluids (MRP fluids) on the surface roughness and material removal rate (MRR) of the workpiece surface in the reciprocating magnetorheological polishing (RMRP) process.

A series of single-factor experiments are performed to evaluate the influence of the concentration of magnetic particles, concentration of abrasive particles and size of abrasive particles on surface processing effects by using the RMRP method. Moreover, the yield stress and viscosity of MRP fluids are studied based on the Bingham plastic model by varying the MRP fluids parameters.

A reasonable parameter of MRP fluids is crucial to the surface roughness and MRR of the workpiece surface, and the optimized parameters are obtained by the single-factor experiments of RMRP. The results are when the concentration of carbonyl iron particles is 40 Vol.%, the concentration of CeO₂ is 5 Vol.% and the size of CeO₂ is 2.5 µm in the MRP fluids, the surface roughness of the workpiece remarkably decreases to 28 nm from the initial 332 nm and the MRR of the workpiece increases to 0.118 mg/min.

In this study, the single-factor experiments for the different parameters of MRP fluids are studied to polish K9 glass by using the RMRP device, and the yield stress and viscosity of MRP fluids are investigated by rheological experiments, which provides reference for a reasonable selection of the MRP fluids parameter in RMRP process.

The purpose of this study is for solving many issues in production that includes processing of complex-shaped profile, machining of high-strength materials, good surface finish with high-level precision and minimization of waste. Among the various advanced machining processes, abrasive jet machining (AJM) is one of the non-traditional machining techniques used for various applications such as polishing, deburring and hole making. Hence, an overview of the investigations done on carbon fiber-reinforced polymer (CFRP) and glass fiber-reinforced polymer (GRFP) composites becomes important.

Discussion on various approaches to AJM, the effect of process parameters on the glass fiber and carbon fiber polymeric composites are presented. Kerf characteristics, surface roughness and various nozzle design were also discussed.

It was observed that abrasive jet pressure, stand-off distance, traverse rate, abrasive size, nozzle diameter, angle of attack are the significant process parameters which affect the machining time, material removal rate, top kerf, bottom kerf and kerf angle. When the particle size is maximum, the increased kinetic energy of the particle improves the penetration depth on the CFRP surface. As the abrasive jet pressure is increased, the cutting process is enabled without severe jet deflection which in turn minimizes the waviness pattern, resulting in a decrease of the surface roughness.

The review is limited to glass fiber and carbon fiber polymeric composites.

In many applications, the use of composite has gained wide acceptance. Hence, machining of the composite need for the study also has gained wide acceptance.

The usage of composites reduces the usage of very costly materials of high density. The cost of the material also comes down.

This paper is a comprehensive review of machining composite with abrasive jet. The paper covers in detail about machining of only GFRP and CFRP composites with various nozzle designs, unlike many studies which has focused widely on general AJM of various materials.