Polished Glass Research Articles

Effect of synergistic CeO2/MoS2 abrasives on surface roughness and material removal rate of quartz glass

Cerium oxide (CeO2) is a primary abrasive frequently used in quartz glass polishing slurry for facilitating glass surface planarisation. However, due to its exorbitant synthesis costs and extremely corrosive as well as toxic reagents in the system, the chemical modification of CeO2 abrasives have limited practical applications. In this work, a novel chemical mechanical polishing slurry for quartz glass incorporating potassium oleate (KOL), deionised water (DIW), cerium dioxide and molybdenum disulphide (MoS2) was developed in this paper to enhance the chemical mechanical polishing (CMP) performance of CeO2-based polishing slurry. KOL creates an alkaline environment for the system, further develops silicate insoluble substances on the quartz glass surface and boosts the material removal rate (MRR) in CMP. MoS2 exhibits a two-dimensional layered nanosheet structure between the abrasive and quartz glass, and then acts as a solid lubricant to prevent excessive mechanical damage, thus increasing the abrasive's wettability. This characteristic helps avoid scratches and other defects on the quartz glass surface. Notably, when the content of KOL and MoS2 in the system is 0.2 wt% and 0.3 wt%, respectively, the surface roughness of the quartz glass surface is 0.48 nm under the scanning area of 15 × 15 μm2 and the MRR is 24.03 μm/h following CMP. The synergistic interaction between CeO2 and MoS2 significantly enhances the abrasive performance on the glass substrate, offering a novel approach for developing polishing fluids that leverage the collaborative effects between abrasives and two-dimensional materials.

FRKVF: High-accuracy motion interpolation for polishing operations using fourth-order Runge-Kutta and velocity flexibility planning

Traditional interpolation algorithms often fail to meet the precision requirements of ultra-precision machining when applied to super-precision polishing machines. Moreover, the processing of fused silica glass optical components is frequently threatened by mechanical impacts due to their fragility. In order to address this issue, this paper proposes a high-precision motion interpolation method based on fourth-order Runge-Kutta and velocity-flexible planning. This method is designed for open-architecture small multi-axis optical polishing machines to polish quartz glass. The algorithm initially employs composite Simpson's rule to calculate the lengths of sub-paths within the polishing trajectory. Based on these length values, flexible velocity planning is executed to ensure the smooth continuity of velocity, acceleration, and jerk during motion interpolation. This reduces the risk of mechanical impacts that could damage the components during the machining process. The introduction of the adaptive fourth-order Runge-Kutta method significantly enhances the parameter point calculation accuracy of NURBS curves. The incorporation of adaptive principles also maintains a higher processing speed, thereby greatly improving processing efficiency. This method comprehensively addresses both the precision of curve interpolation and execution efficiency. Finally, experimental validation is conducted on an open-architecture small multi-axis optical polishing machine. The proposed method based on FRKVF not only mitigates mechanical impacts resulting from discontinuous acceleration, thereby ensuring the machining quality of optical components, but also satisfies the high-precision requirements for processing fused silica optical elements.

Geochemical analysis of extremely fine-grained cryptotephra: New developments and recommended practices

Tephrochronology is a powerful tool used to synchronise and date stratigraphic records by accurate and precise geochemical analysis of deposited volcanic glass shards. However, in many distal stratigraphic records (e.g., polar ice cores) tephra shards are often extremely fine-grained (<10 μm). Geochemical characterisation of these shards is challenging because conventional preparation and analytical techniques require highly polished glass areas >5 μm for electron probe microanalysis (EPMA) to ensure high analytical totals and minimise alkali element loss. Recent method developments have put forward alternative approaches to accurately measure major oxides of small shards: a smaller 3 μm diameter beam, overlapping large (20 μm) beam areas onto supporting epoxy resin, and using scanning electron microscopy with energy dispersive spectrometry (SEM-EDS). However, there has been no direct intercomparison of these alternative techniques, which to date have only been tested on a limited range of glass compositions and tephras that are much larger than the extremely fine-grained material found in distal archives. These issues complicate decision making about the best analytical approach to take when faced with small shards. Here, we provide a new workflow protocol for the analysis of <10 μm tephra by determining the accuracy and precision of alternative SEM-EPMA methods. By analysing a variety of glass standards including those prepared to replicate fine-grained ice-core cryptotephras, we show that a 3 μm EPMA beam is suitable for use on all glass compositions provided the beam current is reduced to 1 nA. When glass areas are too small for a 3 μm beam we show that overlapping this small beam onto epoxy resin is preferable to SEM-EDS analysis. We also provide evidence confirming that using 3–0.2 μm polishes for <5 min increases analytical precision of the most abundant major oxides by up to three times, whilst, crucially, preserving the smallest shards in a sample. By directly applying these alternative methods to ice-core cryptotephra, we demonstrate the data are of suitable accuracy and precision to make robust geochemical correlations. This workflow can be applied to future tephrochronology studies, significantly increasing the quality and quantity of data that are obtained from cryptotephra horizons in distal records.

New insights into the interpretation of the results of four point bending tests on float glass

The four point bending test is one of the most commonly used and standardised tests to determine the mechanical properties of materials. For its use on float glass there are both the ASTM C158-02R17 and European EN 1288-3:2001 standards. However when testing float glass the results tend be a statistical muddle. This impacts the reliability of the design strength of float glass determined using four point bending tests. In an attempt to resolve this problem a series of four point bending tests were conducted which were designed to be more systematic than those previously reported in the literature and which use newly developed digital microscopy techniques for pre- and post-test analysis. By systematically testing, the test results can be divided into different groups based on air side, Sn side and source of failure, allowing the data to be divided into clear and separate statistical groups. Secondly the results can potentially be used to validate the lower bound glass strength theory proposed by Ballarini et al. (J Eng Mech 142(12):04016100, 2016). The glass specimens were industrially cut, ground, chamfered and flat polished on the long sides. Specimens were checked using advanced digital microscopy before and after testing. The results suggest that uni-modal Weibull behaviour only applies above a critical failure stress. Failures at stresses below this critical failure stress as a group have a separate and steeper Weibull slope. This supports Ballarini’s theory for a lower bound failure strength although there are important differences between the air side and Sn side of the specimens which this theory does not currently allow for. These differences seem to be inherent to the differences between the glass and the Sn sides. The results also show that the strength of cut, ground, chamfered and flat polished glass can be high but that inconsistency in process control and the irregular occurrence of surface failures are the main causes for the statistical spread. Digital microscopy can reliably measure the quality of the various surfaces and intersections of surfaces of a glass specimen but there is no absolute relation between the size of a detected defect and the probability that this defect actually leads to failure.

Simulation and experimental investigation of material removal profile based on ultrasonic vibration polishing of K9 optical glass

Ultrasonic vibration polishing (UVP) is an important method for the precision processing of optical glass, which is good for improving surface quality and processing efficiency. So far, the material removal mechanism in UVP is not well understood and the various process parameters involved are not considered. To achieve ultra-precision polishing under optical glass, this paper carries out the axial UVP method. The material removal profile (MRP) is critical to affect the surface accuracy. A new MRP is developed for UVP based on the Urick attenuation model and the proposed material removal coefficient distribution function, considering the dynamic pressure changes under ultrasonic vibration, the attenuation effect of the acoustic pressure propagation process and the inhomogeneous distribution of the abrasive particles in the contact area during the ultrasonic electro-spindle rotation. Through a series of polishing experiments and simulations, the results show that the maximum errors of the actual material removal depth (MRD) and the actual material removal rate (MRR) from the model simulation results are 8.54% and 9.92%, respectively. The accuracy of the model is further demonstrated by the Pearson correlation coefficient. When the amplitude of UVP is 9 µm, Sa and Ra are 60 nm and 68 nm, which are reduced by 37.50% and 22.73%, respectively, compared with conventional polishing. This research can contribute to the deterministic processing of UVP, and provide a theoretical basis for the application of optical glass.

Enhancing dispersion stability and recyclability of ceria slurry with polyacrylic acid for improved glass polishing performance

This study aimed to enhance both the dispersion stability and recyclability of micron-sized ceria slurry in glass polishing by incorporating polyacrylic acid (PAA). PAA with a molecular weight of 240 k was very effective as a dispersant for ceria slurry due to its unique surface adsorption and its characteristics as an anionic polyelectrolyte. Using a 240 k-PAA concentration of 1.0 wt% led to significant improvements in polishing performances, as demonstrated by consistent glass removal rates across recycling cycles. Additionally, the study investigated the physico-chemical properties of polishing slurries, such as specific gravity, particle size, zeta potential, and pH. These properties were effectively maintained with the use of PAA as the dispersant, particularly when KOH was used as a pH adjuster. A 100 µm bag-type filtration system was also introduced for handling the micron-sized ceria slurry, highlighting its practical benefits in slurry management. In conclusion, employing 240 k-PAA as a dispersant in micron-sized ceria slurries for Gorilla glass polishing not only maintains quality and stability across recycling cycles but also provides notable economic advantages by enabling the recycling of the slurry.

Research on Image Mapping Spectrometer Based on Ultra-Thin Glass Layered Mapping.

The imaging quality of the Mapping Imaging Spectrometer (IMS) is crucial for spectral identification and detection performance. In IMS, the image mapper significantly influences the imaging quality. Traditional image mappers utilize a single-point diamond machining process. This process leads to inevitable edge eating phenomena that further results in noticeable deficiencies in imaging, impacting spectral detection performance. Therefore, we propose a manufacturing process for the image mapper based on ultra-thin layered glass. This process involves precision polishing of ultra-thin glass with two-dimensional angles, systematically assembling it into an image mapper. The surface roughness after coating is generally superior to 10 nm, with a maximum angle deviation of less than 3'. This results in high mapping quality. Subsequently, a principle verification experimental system was established to conduct imaging tests on real targets. The reconstructed spectrum demonstrates excellent alignment with the results obtained from the Computed Tomography Imaging Spectrometer (CTIS). We thereby validate that this approach effectively resolves the issues associated with edge eating (caused by traditional single-point diamond machining), and leads to improved imaging quality. Also when compared to other techniques (like two-photon polymerization (2PP)), this process demonstrates notable advantages such as simplicity, efficiency, low processing costs, high fault tolerance, and stability, showcasing its potential for practical applications.

Study on Temporary Unloading for Chatter Vibration Suppression Using Fixed Superabrasive Polishing Stone with Five-Joint Closed-Link Small Robot and Voice Coil Motor Thrust Control

In this study, an existing superfinishing method used for polishing glass surfaces was refined using a five-joint closed-link compact robot with fixed abrasive grains. In previous studies, a voice coil motor was used to control the constant-pressure pressing force while maintaining the polishing force for a relatively short period. However, maintaining the polishing force for long periods is imperative for achieving a high-quality polished surface. Thus, in this study, a strain gauge load cell was adopted in addition to a conventional piezoelectric force sensor to maintain the polishing force for a long period. First, the amounts of DC drift of the piezoelectric force sensor and strain gauge type load cell were compared to confirm the necessity of signal processing as well as the compatibility of long-term force measurement and high-frequency vibration measurement by application. Further, a method was proposed in which the change in the pressing force was recorded from the connected sensor; when the pressing force fluctuated, chatter vibrations were determined to occur, and the pressing force was temporarily set to 0 N. This method could obtain a better polished surface than the proportional-integral-differential (PID) control, which simply controls the pressing force at a constant value. Finally, chatter vibrations could be determined by detecting high-frequency sounds using a sound level meter. Notably, a finely polished surface could be obtained.

Research on picosecond laser-assisted polishing of K9 optical glass: investigation of processing parameters and physical mechanism

Research on picosecond laser-assisted polishing of K9 optical glass: investigation of processing parameters and physical mechanism

Modeling and analysis for material removal and surface roughness in fluid jet polishing of optical glass

Fluid jet polishing (FJP) is a non-contact polishing technology that can fabricate free-form optical surfaces with sub-micron-level form accuracy and nano-level surface roughness, especially for hard and brittle materials. The surface generation model of FJP can be used to guide the determination and optimization of process parameters and is of great significance for understanding the evolution mechanism of surface microtopography. However, predictive models for the microscopic topography of polished surfaces are still lacking. This study established a macroscopic surface profile model for predicting 3D material removal characteristics and surface texture by combining the 3D computer fluid dynamics (CFD) simulation model and single-particle erosion mechanism. A fractal theory-based erosion model has been built to calculate the material removal caused by the erosion of a single abrasive particle on the rough surface; thus, it predicts the micro-topography and surface roughness of the polished samples. A series of polishing experiments were conducted to analyze the feasibility and accuracy of the model quantitatively and study the influence mechanism of process parameters on the material removal characteristics and surface quality. Results indicated that the models could well predict material removal and surface roughness. The prediction accuracy of the surface roughness Ra and maximum removal depth is better than 91.6% and 90%, respectively. It is also found that the material removal rate of FJP could reach 0.517 mm3/min, and the surface roughness convergence rate could reach 62.9%.

Using Acoustic Emissions for an in-situ evaluation of the polishing process and its parameters

Mechanical chemical glass polishing is a complex process with mechanical and chemical interactions. While we have used Acoustic Emissions (AEs) already for basic measurements, we have researched the process and its parameters e.g., the density of the polishing slurry or the glass type for further investigation. We also have carried out crack tests on samples to investigate the crack mechanism. We suggest the further investigation of AEs to improve the above mentioned process and to prepare a transfer of this approach for further processes.

The influence of CeO2 abrasive size on the performance of photocatalytic assisted chemical-mechanical polishing by Y/Pr co-doping strategy

The synergistic effect of photochemical oxidation activity and tribochemical ability of CeO2 material is a necessary prerequisite for the formation of photocatalytic assisted chemical-mechanical polishing (PCMP) abrasive system. However, it is precisely due to the large band gap (∼ 3.2 eV) of CeO2 and the high recombination rate of photogenerated carriers that the improvement of the photocatalytic oxidation activity of traditional CeO2 photocatalysts is greatly limited, thus preventing the further wide application of cerium-based abrasives in PCMP. Based on this, a series of Ce1–2xYxPrxO2 abrasives were synthesized by molten salt method to improve the performance of cerium oxide based polishing paste with PCMP. The physicochemical properties of Ce1–2xYxPrxO2 samples were analyzed by a series of characterization methods. The results show that Ce1–2xYxPrxO2 abrasive has a normal octahedral shape with a particle size of 190 ∼ 260 nm. With the increase of doping amount, the particle size of abrasive decreases gradually, but the photocatalytic activity increases. Compared with undoped CeO2 abrasives, the removal rate (RR = 932.42 nm/min) of quartz glass by Ce1–2xYxPrxO2 abrasive was increased by about 87.10%. At the same time, the surface quality has been significantly improved. A smooth, flawless and low roughness surface was obtained. The improvement in surface quality can be demonstrated by reducing surface roughness (Ra). The Ra of quartz glass decreased to 0.36 nm after Y3+/Pr3+ co-doped CeO2 abrasive by PCMP (the original Ra of glass was 1.08 nm). It was considered that the size of the abrasive had a close relationship with the surface quality and the RR of the polished glass. Meanwhile, characteristic co-doping strategy was conducive to increase the Ce3+ and oxygen vacancy concentration of CeO2 particles, which optimized the separation efficiency of the photogenic carrier of the photocatalyst. This further promoted the generation of oxidizing active substances in the polishing slurry, and therefore expediting the formation and removal of the chemical reaction soft layer. The removal mechanism of Ce1–2xYxPrxO2 abrasives in PCMP process was discussed.

Effect of oxygen flow on electrical and optical properties of ITO films synthesized by magnetron sputtering method

The tin-doped indium oxide thin films were synthesized by DC magnetron sputtering on the surface of polished silicon samples and glass slides in a mixed argon-oxygen atmosphere. The other deposition parameters: operating pressure, magnetron power and substrate rotation speed were kept constant. Thickness and density of thin films were measured by X-ray Reflectometry. The effects of oxygen flow rate and substrate temperature on the optical and electrical properties were investigated. The electrical properties (resistivity, Hall mobility and charge concentration) of the thin films were measured by the Van der Pauw method using the Hall effect. The minimum value of resistivity 0.52 × 10-3 Ohm·cm, and maximum charge mobility 28 cm2V-1s-1 was achieved at an oxygen proportional gas mixture of 2.6% (0.71 sccm). The transmission spectra of the films were measured in the wavelength range from 300 to 1100 nm. The transmittance of all films exceeds 75% in the visible and near-infrared spectral ranges. It was found that increasing the oxygen flow rate and heating of the substrate up to optimal value 150°C led to an increase in the crystallinity of the films and, consequently, to an increase in the Hall mobility and the transmittance.

Dependency of the type of oxygen bonds on the roughness of classically manufactured fused silica surfaces

Glass polishing is a complex process where the formation of the final surface results from several quite different mechanisms – pure mechanical abrasion, wear-induced fretting, flow-induced surface smoothing, and glass modification and removal via chemical reactions. The aim of the study is thus to analyse the chemical composition and surface roughness throughout the entire classical optics manufacturing process of fused silica, which includes the production steps of cutting, grinding or lapping, and polishing, using X-ray photoelectron spectroscopy and atomic force microscopy. It is shown that the analytical results are in good accordance with the polishing theory initially suggested by Beilby, Bowden and Hughes in the 1920s and 1930s. The decomposition of the oxygen peak from the detail XPS spectra allowed a subdivision of Si–O bonds into silicon dioxide and silanol such as Si–OH or Si(OH)4, which enabled a direct correlation between the SiO2 and silanol concentration and the surface roughness occurring for the particular manufacturing steps.

Gastric acid challenge of lithium disilicate–reinforced glass–ceramics and zirconia-reinforced lithium silicate glass–ceramic after polishing and glazing—impact on surface properties

ObjectivesTo investigate the impact of simulated gastric acid on the surface properties of lithium disilicate–reinforced glass–ceramics and zirconia-reinforced lithium silicate glass–ceramic after certain polishing and glazing procedures.Materials and methodsFour different types of square-shaped specimens (10 × 10 × 2 mm3, n = 13) were manufactured: lithium disilicate–reinforced glass–ceramic milled and polished (LDS-P); milled, polished, and glazed (LDS-PG); milled, glazed, and no polishing (LDS-G); and milled and polished zirconia-reinforced lithium silicate glass–ceramic (ZR-LS). Specimens were immersed in hydrochloride acid (HCl 0.06 M, pH 1.2) to simulate gastric acid irritation and stored in the acid for 96 h in 37 °C. Specimen weight, surface gloss, Vickers surface microhardness and surface roughness (Ra, Rq, with optical profilometer), and surface roughness on nanometer level (Sq, Sal, Sq/Sal, Sdr, Sds with atomic force microscope) were measured before and after the acid immersion.ResultsZR-LS specimens lost significantly more weight after acid immersion (p = 0.001), also surface microhardness of ZR-LS was significantly reduced (p = 0.001). LDS-G and LDS-PG showed significantly lower surface roughness (Sa, Sq) values compared to LDS-P before (p ≤ 0.99) and after (p ≤ 0.99) acid immersion and ZR-LS after acid immersion (p ≤ 0.99).ConclusionsGastric acid challenge affects the surface properties of lithium disilicate–reinforced glass–ceramic and zirconia-reinforced lithium silicate glass–ceramic. Glazing layer provides lower surface roughness, and the glazed surface tends to smoothen after the gastric acid challenge.Clinical relevanceSurface finish of lithium disilicate–reinforced glass–ceramic and zirconia-reinforced lithium silicate glass–ceramic has a clear impact on material’s surface properties. Gastric acidic challenge changes surface properties but glazing seems to function as a protective barrier. Nevertheless, also glazing tends to smoothen after heavy gastric acid challenge. Glazing can be highly recommended to all glass–ceramic restorations but especially in patients with gastroesophageal reflux disease (GERD) and eating disorders like bulimia nervosa.

ELID Dressing Behaviors of Non-Abrasive Iron-Based Grinding Wheels

Non-abrasive iron-based grinding diamond wheels, lacking abrasive particles, negate the concern of detached passivated abrasives scratching the polished surface. During the Electrolytic In-Process Dressing (ELID) polishing process, α-Fe2O3 particles form on the oxide film surface of the iron-based grinding diamond wheel devoid of abrasives. These particles assume the role of the grinding diamond wheel for polishing. Therefore, the ELID electrolytic performance and the oxide film formation performance of the non-abrasive iron-based grinding diamond wheel significantly influence the formation of α-Fe2O3 particles and the subsequent ELID polishing performance. Our studies investigating the ELID dressing behavior of the non-abrasive iron-based grinding diamond wheel have analyzed the influence mechanism of the electric field, flow field, and pulse energy on its ELID dressing. Moreover, the roundness of the ELID dressing grinding diamond wheel, oxide film properties, and α-Fe2O3 particle content were measured, and plate glass was polished using the ELID non-abrasive iron-based grinding diamond wheel. The results illustrate that the non-abrasive iron-based grinding diamond wheel exhibits excellent ELID dressing performance. The diamond wheel’s roundness is less than 0.001 mm, the oxide film uniformly covers the surface, the content of α-Fe2O3 particles is evenly distributed, and the surface accuracy of the polished plate glass is approximately 0.5 nm. These findings provide a compelling case for the continued use and development of grainless iron-based grinding diamond wheels in precision grinding operations.

A novel method has been developed to efficiently recover valuable lead, zinc, and rare earth elements from hazardous waste generated by glass polishing

Discovering new processing routes to put waste to use in the manufacturing of high-value products is essential to the success of the circular economy. A glass polishing waste containing 16.4% PbO, 0.672% ZnO and 7.296% rare earth elements (REEs) oxides was subjected to this work. The current research looked into the feasibility of adopting a sequential three-stage leaching procedure to selectively recover Pb, Zn, and REEs from hazardous glass polishing waste (HGPW). First-stage leaching with 1 M H2SO4 at 80 °C for 90 min extracted 75–99.9% of contaminant heavy metals such Fe, Ni, Co, and Cu, leaving behind insoluble residue containing the metals of interest. In the second stage of leaching, the sodium hydroxide solution extracted Pb and Zn from the first spend residue. Using shrinking core models, we were able to assess the kinetics of lead and zinc dissolution. The activation energy was determined to be 32.16 kJ/mol for Pb and 34.59 kJ/mol for Zn. In the final step, the REEs were extracted from the dried alkali-treated residue by leaching it with concentrated H2SO4 at higher temperatures. For the technological recovery of Pb, Zn, and REEs from glass polishing waste, a flow chart was created.

Modeling Wavelength Dependent Mid‐Infrared (5.5–25 μm) Optical Constants of Silicate Glasses: A Genetic Algorithm Approach

AbstractWavelength‐dependent mid‐infrared (400–1,800 cm−1; 5.56–25 μm) optical constants (real and imaginary indices of refraction; n and k) are determined using reflectance spectra at a spectral sampling of 4 cm−1 for several silicate glasses of varying SiO2 wt% which include (a) basaltic volcanic glass from Kīlauea, Hawaii, (b) synthetic andesite, (c) two synthetic dacites, (d) obsidian volcanic glass from Mount Lassen, California, (e) synthetic rhyodacite, and (f) rhyolitic volcanic glass from Mexico. Because glasses are optically isotropic, no specific orientation was required for spectral measurements, and polished glass samples were measured at random orientations using micro‐FTIR spectrometer. Lorentz‐Lorenz dispersion theory and Fresnel reflectance model for high symmetry materials were used to model the optical constants by optimizing oscillator parameters in modeled spectra to match laboratory spectra. A genetic algorithm (GA) approach automatically finds the natural oscillators and their parameters for each spectrum, and then uses these parameters in a non‐linear least squares optimization routine. The study compared spectral parameters such as Christiansen feature, reststrahlen bands (RBs), and the peaks centered around 860–1,100 (peak 1) and 400–480 cm−1 (peak 2) of n and k to their respective SiO2 wt% of the glasses. CF, RBs, peak 1 of n and k, and peak 2 of n shift to higher wavenumbers with increased SiO2 wt%, whereas peak 2 of k shifts to lower wavenumbers with increased SiO2 wt%. Derived optical constants of these glasses will improve quantitative abundance mapping of volcanic materials on the surfaces of silicate targets in the Solar System.

Improved CNC ball-end magnetorheological finishing process for borosilicate glass polishing

ABSTRACT This research aims to present an improved design of the Ball-End Magnetorheological Finishing (BEMRF) tool with the capability of being mounted on a CNC milling machine for polishing borosilicate glass (Bk7) lenses. Subsequently, the new BEMRF tool was designed, researched, and adjusted with magnetostatic simulation in Ansys Maxwell software. A response surface method experimental investigation was conducted to discover the optimized constitution of the magnetorheological fluid’s abrasive and carbonyl iron particles used for finishing operation on flat Bk7 glass. The simulation results and afterward measurements with a Gauss meter showed that changes in the BEMRF tool improved the variation in the density of magnetic flux in the polishing gap. At the optimum fluid constituents of 16 vol% abrasives and 29 vol% carbonyl iron particles, a 59% improvement in surface roughness was achieved. The proposed CNC tool found an appropriate way to finish Bk7 glass.

Applying a new artificial intelligence algorithm to Optimize technological parameters when polishing K9 optical lens materials by magnetized liquid solution

ABSTRACT In order to achieve a high-quality superfine surface on K9 glass, a novel algorithm was developed for addressing optimisation challenges in high-precision machining using magnetised liquid solution. This algorithm employs a collective global exploration developed based on AI (Artificial Intelligence) inspiration, which effectively coordinates various nonlinear systems encountered during the machining process. By integrating multiple nonlinear systems and utilising straightforward physical techniques, the goal is to create a powerful artificial intelligence algorithm in optimising nonlinear systems (AIONS). This algorithm aims to achieve the same level of versatility and rapid convergence observed in enhancing surface quality during the burnishing of optical material K9. To demonstrate the effectiveness of the AIONS algorithm, benchmark functions were analysed in conjunction with optimising the K9 optical glass polishing process. Polishing experiments were conducted to determine the ideal technical parameters using the new algorithm and a straight permanent magnetic yoke surface finishing approach. The analysis and experimental results revealed that when polishing K9 optical glass materials with a permanent-magnetic yoke field and employing a magnetised liquid solution (MLS) with technological parameters guided by the AIONS algorithm, exceptionally smooth surface finish with an Ra value of 0.480 nm was achieved, leaving no scratches on the polished surface. The objective of this study is to provide valuable insights into optimising the surface polishing of challenging materials like K9 optical glass and other materials used in the optical industry.