3D Printing Technology Research Articles

Learning program enhances rehabilitation professionals’ perceived ease of using 3d printing: a pilot randomized controlled trial

The pilot study evaluated whether a learning program enhances a positive perception of 3D printing technology in rehabilitation professionals. Physical therapists, occupational therapists and speech-language-hearing therapists were recruited from a rehabilitation department in a middle-sized hospital. Participants were randomized to the control group (n = 13) or the intervention group (n = 14). An eight-week learning program consisted of a lecture on using a 3D printer and related software, a group discussion to integrate 3D printing into their clinical practices, and the implementation in their workplace. Outcome measures included the perception of 3D printing technology assessed by the Japanese version of the modified Technology Acceptance Model questionnaire for 3D printing technology (TAM-J). Assessment time points were pre-and post-intervention. As a result, all participants in the intervention group became capable of producing 3D-printed customized assistive devices. In the within-group analyses, the intervention group showed significant improvements in the TAM-J perception ease of use score (p = 0.012) with a large effect size (r = 0.75). Between-group analyses showed that the intervention group gained an additional improvement in the TAM-J perception ease of use score (p = 0.027) with a moderate effect size (r = 0. 43), indicating a significant improvement in the perceived ease of use of 3D printing technology in the intervention group. These observations suggest the 3D printing learning program could provide rehabilitation professionals with a positive perception of the technical aspect of 3D printing in their workplace.

Viscosity measurements of selected lunar regolith simulants

Abstract In the context of evaluating lunar construction options, this study focuses on characterizing the viscosities and glass transition properties of lunar regolith simulants to support the development of additive manufacturing processes using molten regolith. Employing the modular TUBS lunar regolith simulant system, we measured the viscosities of different simulants through high-temperature experiments conducted between 1,051 °C and 1,490 °C using Concentric Cylinder viscometry in air. Additionally, Differential Scanning Calorimetry (DSC) was utilized to evaluate the glass transition temperatures, which were in the range between 689 °C and 815 °C. The measured viscosity data were parameterized by the Vogel—Fulcher—Tammann (VFT) equation, adept at describing the viscosities and related properties of silicate liquids. The measured viscosities were compared with the predicted values of six viscosity models. It was shown that the model by Sehlke and Whittington predicts the viscosities of the tested lunar regolith simulants at superliquidus temperatures best, whereby no model adequately predicts viscosities at the glass transition temperature, indicating a need for further research in this area. We infer that 3D printing technologies based on molten lunar regolith, are viscosity-wise best constrained to highland regions. The reduced environment on the Moon influences the 3D printing process in a positive manner.

A 3D-printing metasurface-augmented half-circle Maxwell fisheye lens for millimetre-wave analogue beamforming

Abstract This article presents a 2D metasurface-augmented half-circle Maxwell fisheye lens (HMFL) designed to move its focal axis to a targeted direction with a maximum elevation angle of 45 degrees, suitable for switches and power division networks in the millimetre wave (mmWave) band. This metasurface-augmented beamformer enables consistent analogue performance across a bandwidth of 22 - 32 GHz. The proposed beamformer features a reflective metasurface consisting of 2x40 Phoenix unit cells and is integrated with a 10-dielectric zone HMFL in the diameter segment opposite the antenna source. A horn antenna feed is used for excitation in normal and oblique incidences of -15 and -30 degrees. The designed lens prototype was fabricated with 3D-printing technology and printed metasurfaces for several particular cases of focal displacement. The measurements of the proposed HMFL beamformer are presented, demonstrating a close correlation between simulated and experimental results.

Experimental study on buildability and mechanical properties of 3D printing cob

The application of 3D printing technology to earth buildings conforms to the development concept of low carbon, green and intelligent construction. The key issue lies in the development of earth material with both favorable buildability and sufficient mechanical properties. In this study, the printing parameters of mixture for 3D printing with different water contents were optimized. The optimum water content of 3D printing cob was determined based on the buildability. The result shows that when the flow spreading diameter is between 140 mm and 160 mm, 3D printing cob has good buildability performance. The optimum water content is 24.6 %. In addition, anisotropic performance was analyzed by compressive strength tests from three orthogonal directions. In particular, according to the test results of single printing limit height and yield stress, the buildability of 3D printing cob wall was analyzed. The building strategy of the printing divided into multiple times was obtained.

Evaluating the outcomes of three dimensional printing-assisted osteotomy on treating varus knee deformity from old tibial plateau fractures.

This study aimed to evaluate the outcomes of three-dimensional (3D) Printing-Assisted Osteotomy in treating varus knee deformity from old tibial plateau fractures. The study retrospectively analyzed patients with varus deformity induced by old-tibial plateau fractures between January 2019 and June 2023. All patients utilized 3D printed models for surgical planning. The Lysholm Knee Score (LKS), Visual Analog Scale (VAS) and Knee Society Score (KSS) were measured for functional outcomes. Medial Proximal Tibial Angle (MPTA), Joint Line Convergence Angle (JLCA), Mechanical Axis (%MA), Medial Tibial Plateau Depression (MTPD), and Femorotibial Angle (FTA) were measured for radiological outcomes. 15 patients (12 males and 3 females) were included in this study and followed up for 21.9 ± 8.6 (range, 12 to 28) months. Healing of the osteotomy sites were achieved in all patients at 15.8 ± 1.5 (range, 13 to 18) weeks. The knee varus deformities were significantly corrected as reflected by %MA (2.13 ± 13.1°(range, -20 to 22) versus 57.06 ± 9.8°(range, 41 to 70), p < 0.01), FTA (186.7 ± 3.2°(range, 181 to 193) versus 172.3 ± 2.1°(range, 169 to 175), p < 0.01), JLCA (5.8 ± 1.7°(range, 3 to 8) versus 1.3 ± 0.8°(range, 0 to 3), p < 0.01), and MPTA (5.6 ± 1.2°(range, 3 to 8) versus 1.2 ± 1.1°(range, -1 to 3), p < 0.01). Postoperative knee function showed dramatic improvements as reflected by VAS (4.6 ± 1.6 (range, 1 to 7) versus 0.7 ± 0.9 (range, 0 to 2), p < 0.01), KSS (50.1 ± 16.5 (range, 27 to 88) versus 88.5 ± 5.2 (range, 80 to 95), p < 0.01), and LKS (49.5 ± 10.2 (range, 37 to 69) versus 89.2 ± 2.5 (range, 87 to 94), p < 0.01). 3D printing technology provides a valuable tool for understanding deformities and optimizing osteotomy strategies, thereby improving surgical efficacy and treatment outcomes. Its clinical application is highly recommended.

RAFT Polymerization for Advanced Morphological Control: From Individual Polymer Chains to Bulk Materials.

Control of the morphology of polymer systems is achieved through reversible-deactivation radical polymerization techniques such as Reversible Addition-Fragmentation chain Transfer (RAFT). Advanced RAFT techniques offer much more than just "living" polymerization - the RAFT toolkit now enables morphological control of polymer systems across many decades of length-scale. Morphological control is explored at the molecular-level in the context of syntheses where individual monomer unit insertion provides sequence-defined polymers (single unit monomer insertion, SUMI). By being able to define polymer architectures, the synthesis of bespoke shapes and sizes of nanostructures becomes possible by leveraging self-assembly (polymerization induced self-assembly, PISA). Finally, it is seen that macroscopic materials can be produced with nanoscale detail, based on phase-separated nanostructures (polymerization induced microphase separation, PIMS) and microscale detail based on 3D-printing technologies. RAFT control of morphology is seen to cross from molecular level to additive manufacturing length-scales, with complete morphological control over all length-scales.

Advancing optical transparency in 3D‐printed PLA parts using chemical post‐processing

AbstractFused filament fabrication (FFF) is an increasingly popular three‐dimensional (3D) printing technology known for its ability to produce complex 3D models at a low‐cost using polymer materials. Despite its advantages, the poor surface finish and high layer resolution in FFF‐printed parts have hindered its wider adoption, particularly for applications requiring high transparency. Thus, the current study investigates the transparency evaluation of chemically post‐processed 3D‐printed transparent polylactic acid (PLA) parts, focusing on enhancing optical transparency. Fused Filament Fabrication was employed to produce transparent parts made from PLA filament, which were subsequently treated at various time settings using various solvents, including tetrahydrofuran (THF), chloroform or trichloromethane (TCM), and ethyl acetate (EA). This study examines the impact of chemical post‐processing on the surface roughness, transparency, mechanical properties, and dimensional accuracy of solvent treated parts. It has been found that the THF solvent with 40 s of immersion time resulted in a maximum transmittance of 74.66% and minimum surface roughness of 1.777 μm. Based on this finding a case study was also conducted to apply the findings of the current investigation to a practical application. The findings highlight the potential of chemical‐based post‐processing techniques to improve the optical properties of 3D printed PLA, offering a promising approach for applications in optics, medical devices, and consumer goods requiring transparent components.Highlights Effect of chemical post‐processing on 3D‐printed PLA parts was investigated. Tetrahydrofuran, chloroform, and ethyl acetate were used as solvents. Surface roughness, transparency, hardness, and dimensional accuracy were analyzed. Reported a maximum transmittance of 74.66% and minimum surface roughness of 1.777 μm.

Application of 3D printing in bacterial detection

Diseases caused by bacterial infections, especially pathogen variations and drug-resistant bacteria, are a serious threat to human health globally. Accurate and rapid identification of bacterial pathogens is essential for early diagnosis of infections and timely treatment of disease. At present, the routine diagnostic methods for identifying bacterial pathogens in clinic are bacterial culture, immunological detection, genetic analysis, etc. These methods occupy foundational position for bacterial detection that favors for clinical diagnosis of pathogen infection in daily life. Notably, 3D printing technology, together with 3D bioprinting technology, provides more options for bacterial detection due to its personalized design and manufacturing. Compared with traditional methods, 3D printing provides a more convenient, rapid and accurate bacterial detection platform, thus meeting the urgent needs of clinical and scientific research. Here, we have summarized the research progress and given a comprehensive review of 3D printing technology in bacterial detection, including bacterial detection sensors, microfluidic chips, bioprinting microarray technology, AI and spectroscopy technology, providing a scientific reference and filling in gaps in 3D printing-assistance bacterial detection. At the same time, technical advantages, challenges and future development trends will also be discussed in related healthcare fields.

High Efficiency Producing Technology Applied in Metal Optical Lens by 3D Wax Printing Combined with Investment Casting

3D printing technology can easily and quickly produce small batch models and full-size parts, which has obvious and important benefits in shortening development time. Since metals exhibit excellent mechanical strength and high wear resistance, metal additive manufacturing (MAM) is a popular technology for making metal parts. However, metal powders and 3D-printing machines are costly, which increases the difficulty of achieving mass production through MAM. In this study, the 3D wax printing and investment casting (WPIC) approach was developed to manufacture high-quality metal optical lenses with high efficiency and low cost. The manufactured lenses had a diameter of 38.1 mm, two radii of curvature (15 and 90 mm), and a cooling channel. These lenses were manufactured through 3D printing by using wax patterns produced through investment casting. The manufacturing efficiency and machining accuracy of the lenses produced using the proposed method were compared with those of lenses produced through MAM and investment casting. The results indicated that the total costs of manufacturing an optical lens through MAM and investment casting were nine and eight times greater, respectively than that of manufacturing an optical lens through WPIC. In addition, the surface roughness of metal lenses manufactured through WPIC was 45% lower than that of lenses manufactured through MAM. Finally, the time required to manufacture 50 metal lenses was only 15 days when WPIC was used; the corresponding time was 25 days and 6 months when MAM and investment casting were used, respectively. According to the above-mentioned results, the WPIC process has excellent advantages in product manufacturing cost and developing schedule over MAM and traditional methods of investment casting.

Towards industry-ready additive manufacturing: AI-enabled closed-loop control for 3D melt electrowriting.

Melt electrowriting (MEW) is an emerging high-resolution 3D printing technology used in biomedical engineering, regenerative medicine, and soft robotics. Its transition from academia to industry faces challenges such as slow experimentation, low printing throughput, poor reproducibility, and user-dependent operation, largely due to the nonlinear and multiparametric nature of the MEW process. To address these challenges, we applied computer vision and machine learning to monitor and analyze the process in real-time through imaging of the MEW jet between the nozzle-collector gap. To collect data for training we developed an automated data collection methodology that eases the experimental time from days to hours. A feedforward neural network, working in concert with optimization methods and a feedback loop, is used to develop closed-loop control ensuring reproducibility of the printed parts. We demonstrate that machine learning allows streamlining the MEW operation via closed-loop control of the highly nonlinear 3D printing technology.

Walnut shell/phenolic resin carbon electrodes via laser sintering and KOH activation

Currently, the application of 3D-printed biomass-based carbon electrodes is hindered by their suboptimal performance. This study utilizes walnut shell powder as a carbon source and employs Selective Laser Sintering (SLS) technology for the efficient 3D printing of a double-helix carbon precursor. High-performance biomass-based carbon electrodes are prepared through carbonization and KOH activation. Comparative studies on the microstructure and electrochemical performance of the carbonized and activated samples were conducted. Experimental results demonstrate that KOH activation significantly enhances the microstructure of the carbon electrodes, leading to marked improvements in their electrochemical performance. During desalination experiments, the carbon electrodes exhibited excellent ion removal efficiency, with a maximum conductivity reduction rate of 0.2 μS/cm·min, confirming their feasibility in seawater desalination applications. This research validates the potential of walnut shell biomass for the preparation of 3D-printed carbon electrodes, addressing bottlenecks in traditional carbon electrode manufacturing processes while promoting efficient biomass utilization and environmental protection.

Evaluating the Educational Impact of 3D-Printed Toys in Elementary Settings: A Mixed-Methods Study

This study explores the impact of integrating the use of disruptive technologies on 3D-printed toys within elementary education through a mixed-methods approach, combining an experimental design with qualitative interviews. Focusing on the potential of disruptive technologies to innovate educational practices, we divided participants into control and experimental groups, the latter engaging with the 3D-printed educational toys. Despite the innovative application of 3D printing technology in educational settings, our findings reveal no significant differences in the learning outcomes between the two groups. Therefore, this research contributes to the literature on educational innovation, suggesting that the mere introduction of novel technologies, such as 3D printing, may not be sufficient to enhance learning effectiveness. Regarding practical implications, the study is aimed at scholars, teachers, and educational managers, to underscore the necessity of a critical assessment of educational tools and calls for further investigation into how technology integrates into pedagogical frameworks to truly benefit elementary education. Received: 12 July 2024 / Accepted: 31 October 2024 / Published: 05 November 2024

The accuracy and efficiency of design and development of 3D printed integral anatomical acetabular prosthesis in total hip arthroplasty for Crowe type Ⅱ and Ⅲ developmental dysplasia of the hip

Objective: To compare the accuracy and efficiency between the model development method and the software development method, which design and develop 3D printed integral anatomical acetabular prosthesis to be used in total hip arthroplasty(THA) for patients with Crowe type Ⅱ and Ⅲ developmental dysplasia of the hip(DDH). Methods: Fifteen patients with end-stage hip osteoarthritis due to Crowe type Ⅱ and Ⅲ DDH who underwent THA in the Orthopedics Department of the First Affiliated Hospital of Bengbu Medical College between January 2015 and June 2023 were selected in this study retrospectively. There were 1 male (1 hip) and 14 females (17 hips) with a mean age of (55.1±9.1) years. There were 12 hips with Crowe type Ⅱ, 6 hips with Crowe type Ⅲ. The preoperative pelvis three-dimensional CT data in those patients were used to design integral anatomical acetabular prosthesis. The model development group used 3D printing technology to print life-size pelvis models. The acetabulum was reamed and the acetabulum cup was inserted into the socket according to conventional THA procedures. The bone defect above the acetabulum cup was filled with bone wax. The Mimics and 3-matic software were used to simulate the THA procedures, design and install the integrated anatomical acetabular prosthesis in the software development group. The operation time, the size of the acetabular cup, the volume and surface area of the acetabulum bone defect, the acetabular cup's inclination and anteversion, the horizontal distance and the vertical distance of hip rotation center were compared between the two methods. Results: The study in the two groups were all based on the data of 18 hips in the 15 patients. The horizontal and vertical distances of rotation center in the model development group and software development group was (32.08±1.80) mm, (32.17±2.40) mm and (14.36±1.53) mm, (15.11±1.45) mm, respectively (both P>0.05). The cup size in model development group was (48.56±1.15)mm, and it was (48.77±1.22) mm in the software group (P=0.160). The anteversion and inclination of the acetabular cup in the model and software groups were 23.79°±6.31°, 30.49°±11.03° and 15.17°±0.52°, 40.24°±0.58°, respectively (both P<0.01). The volume and surface area of the acetabulum bone defect in the model development group was (5.06±2.86) mm3 and (8.31±2.21) mm2, respectively, while it was (4.01±2.56)mm3 and (6.83±2.71) mm2, respectively, in the software development group (both P<0.05). The work time in the model development group was (24.43±0.68) h and (0.47±0.12) h in the software development group, respectively (P<0.001). Conclusion: Compared with the 3D printing model development method, the application of Mimics and 3-matic software to design and develop integrated anatomical acetabular prosthesis in total hip arthroplasty for Crowe type Ⅱ and Ⅲ DDH show advantages of convenience, high efficiency and more accuracy.

Improving mechanical properties of 3D printed products through honeycomb structure and deep learning optimization

The use of three-dimensional (3D) Printing has rapidly grown due to its various applications in daily life. However, products made with this technology are not widely adopted because their quality is not yet seen as equal to that of products made with traditional materials. To address this issue, a honeycomb structure model was developed to improve the mechanical properties of the items created using 3D printing technology. This model not only saves materials, but also reduces printing time compared to previous models. The honeycomb structure was designed using a theoretical model, and its components were modified to ensure compatibility with the 3D printing extrusion method. Moreover, deep learning was used to optimise the honeycomb structure model’s boundary conditions by generating contour curves through linear interpolation. This process significantly improved the mechanical strength of the honeycomb structure model compared to structures made using 3D printing technology. The theoretical findings were validated through various material tensile tests conducted under different scenarios. As a result, this model can be used in various industries and products that use 3D printing technology, thanks to the critical role that deep learning in improving its mechanical properties.

Evaluation of the Accuracy of 3D Printed Patient-Specific Brain Biopsy Guide Using 3D Volume Rendering Technique in Canine Cadavers.

The objective of this study was to evaluate the accuracy of a CT-based, 3D-printed, patient-specific brain biopsy guide (3D-psBBG) through the application of a transfrontal approach in canine cadavers. A total of ten canine cadavers, with weights ranging from 4.36 to 14.4 kg, were subjected to preoperative CT scans to generate 3D skull models. Customized biopsy guides were created based on these models and manufactured using 3D printing technology. Twenty spinal needle insertions were performed, and the accuracy of needle placement was evaluated through both CT and 3D volume-rendering techniques. The mean needle placement error was 2.1 mm, with no significant differences observed between insertions targeting the fronto-olfactory and piriform lobes. The 3D volume-rendering method demonstrated superior accuracy compared to the CT method, with statistically significant differences in placement errors for both targets. The average time required for the design and manufacture of the guides was 249 min. These findings indicate the high accuracy and potential clinical application of CT-based 3D-psBBG for improving diagnostic outcomes in veterinary neurology.

Application of 3D Printing Technology in Microreactor Fabrication

Application of 3D Printing Technology in Microreactor Fabrication

Comprehensive Study of Stereolithography and Digital Light Processing Printing of Zirconia Photosensitive Suspensions

Zirconia ceramics are used in a wide range of applications, including dental restorations, bioimplants, and fuel cells, due to their accessibility, biocompatibility, chemical resistance, and favorable mechanical properties. Following the development of 3D printing technologies, it is possible to rapidly print zirconia-based objects with high precision using stereolithography (SLA) and digital light processing (DLP) techniques. The advantages of these techniques include the ability to print multiple objects simultaneously on the printing platform. To align with the quality standards, it is necessary to focus on optimizing processing factors such as the viscosity of the suspension and particle size, as well as the prevention of particle agglomeration and sedimentation during printing, comprising the choice of a suitable debinding and sintering mode. The presented review provides a detailed overview of the recent trends in preparing routes for zirconium oxide bodies; from preparing the suspension through printing and sintering to characterizing mechanical properties. Additionally, the review offers insight into applications of zirconium-based ceramics.

Preparation of Cf/Si3N4 composites based on vat photopolymerization combined with precursor infiltration and pyrolysis

AbstractThe development of vat photopolymerization (VPP) 3D printing technology has created the conditions for the fabrication of complex structured Si3N4 ceramics. However, Si3N4 ceramics produced through VPP often lack sufficient mechanical properties, which limiting their applications. This study introduces short carbon fibers (Cf) into the VPP‐Si3N4 ceramics, combined with the polymer infiltration and pyrolysis (PIP) process, to prepare Cf/Si3N4 composites. The effect of Cf content on slurry preparation, green part printing, and mechanical properties of the Cf/Si3N4 composites was systematically investigated. The results indicate that Cf significantly enhances the mechanical properties of Cf/Si3N4 composites. At 6 wt.% Cf content, the samples exhibit the highest strength and fracture toughness, reaching 183.2 MPa and 6.2 MPa·m1/2, respectively, representing increases of 29.7% and 92.3% compared to samples without Cf. The improvement in mechanical properties is partly due to the ‘pinning effect’ of Cf, which enhances interlayer bonding strength in the printed green parts, positively impacting the overall mechanical properties of the composites. Additionally, inherent toughening mechanisms of Cf, such as fiber pull‐out, crack deflection, and crack bridging, further enhance the composite's mechanical properties. This study confirms the feasibility of using Cf to enhance the mechanical properties of VPP‐Si3N4 ceramic.

Next-generation 3D printed multipurpose prevention intravaginal ring for prevention of HIV, HSV-2, and unintended pregnancy

Globally, nearly half of all pregnancies are unintended, ~1.3 million new human immunodeficiency virus (HIV) infections are reported every year, and more than 500 million people are estimated to have a genital herpes simplex virus (HSV-2) infection. Here we report the first 3D printed multipurpose prevention technology (MPT) intravaginal ring (IVR) for prevention of HIV, HSV-2, and unintended pregnancy. The IVRs were fabricated using state-of-the-art Continuous Liquid Interface Production (CLIP™) 3D printing technology using a biocompatible silicone-urethane based resin. Anti-HIV drug (Dapivirine, DPV), anti-herpes drug (Pritelivir, PTV) and a contraceptive drug (Levonorgestrel, LNG) were loaded in a macaque size IVR (25 mm outer diameter, OD; 6.0 mm cross-section, CS) allometrically scaled from the human size (54 mm OD; 7.6 mm CS) IVR analogue. All three active pharmaceutical ingredients (APIs) were loaded in the IVR using a single-step drug loading process driven by absorption. DPV, PTV, and LNG elicited zero-order release kinetics in vitro in simulated vaginal fluid (SVF) at pH 4 and pH 8 relevant to human and macaque vaginal pH respectively. CLIP 3D printed MPT IVRs remained stable after 6 months of storage at 4 °C with no change in physical, dimensional, or mechanical properties and no change in drug concentration and absence of drug degradation byproducts. The MPT IVRs elicited sustained release of all three APIs in macaques for 28 days with median plasma concentrations of 138 pg/mL (DPV), 18,700 pg/mL (PTV), and 335 pg/mL (LNG). Safety studies demonstrated that the MPT IVRs were safe and well tolerated in the macaques with no observed change or abnormalities in vaginal pH and no significant changes in any of the 22 mucosal cytokines and chemokines tested including pro-inflammatory (IL-1β, IL-6, IL-8, IFN-γ, TNF-α, IL-17, IL-18) and anti-inflammatory (IL-10, IL-12) cytokines while the MPT IVR was in place or after its removal. Additionally, MPT IVRs elicited no observed alterations in systemic CD4+ and CD8+ T cells during the entire study. Collectively, the proposed MPT IVR has potential to expand preventative choices for young women and girls against unintended pregnancy against two highly prevalent sexually transmitted infections (STIs).

Surface Quality as a Factor Affecting the Functionality of Products Manufactured with Metal and 3D Printing Technologies.

Surface engineering is one of the most extensive industries. Virtually all areas of the economy benefit from the achievements of surface engineering. Surface quality affects the quality of finished products as well as the quality of manufactured parts. It affects both functional qualities and esthetics. Surface quality affects the image and reputation of a brand. This is particularly true for cars and household appliances. Surface modification of products is also aimed at improving their functional and protective properties. This applies to surfaces for producing hydrophobic surfaces, anti-wear protection of friction pairs, corrosion protection, and others. Metal technologies and 3D printing benefit from surface technologies that improve their functionality and facilitate the operation of products. Surface engineering offers a range of different coating and layering methods from varnishing and painting to sophisticated nanometric coatings. This paper presents an overview of selected surface engineering issues pertaining to metal products, with a particular focus on surface modification of products manufactured by 3D printing technology. It evaluates the impact of the surface quality of products on their functional and performance qualities.