Big-and-dull or small-and-sharp: A comparison of specific energy, wheel wear, surface-generation mechanisms and surface characteristics when grinding with Al2O3 and CBN to achieve a given surface roughness

One of the remarkable achievements of nanotechnology is the ability to achieve nanometric surface finishes in single-point diamond turning of high-precision components for complex optical surfaces. A better understanding of the surface generation mechanisms is of prime importance for the development for the prediction of the surface roughness. This paper presents a study of mechanisms of nano-surface generation in single-point diamond turning of various types of materials.

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Effect of Polymer, Road Surface, and Driving Conditions on Wear Surface Characteristics of Tire Treads

Tire Science and Technology ◽

10.2346/1.2167171 ◽

1973 ◽

Vol 1 (4) ◽

pp. 354-362 ◽

Cited By ~ 2

Author(s):

F. R. Martin ◽

P. H. Biddison

Keyword(s):

Wear Surface ◽

Surface Characteristics ◽

Road Surface ◽

The Other ◽

Mechanical Degradation ◽

Textured Surface ◽

Test Track ◽

Driving Conditions ◽

Styrene Butadiene ◽

Cylindrical Particles

Abstract Treads made with emulsion styrene-butadiene copolymer (SBR), solution SBR, polybutadiene (BR), and a 60/40 emulsion SBR/BR mixture were built as four-way tread sections on G78-15 belted bias tires, which were driven over both concrete and gravel-textured highways and on a small, circular, concrete test track. The tires were front mounted. When driven on concrete highway, all except the BR tread had either crumbled- or liquid-appearing surfaces, thought to have been formed by mechanical degradation or fatigue. When cornered on concrete, these materials formed small cylindrical particles or rolls. The BR tread had a smooth, granular-textured surface when driven on concrete highway and a ridge or sawtooth abrasion pattern when cornered on concrete. All the materials appeared rough and torn when run on gravel-textured highway. The differences in wear surface formed on BR tread and the other three are thought to be due primarily to the relatively high resilience of BR.

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Biofilm inhibition and bactericidal activity of NiTi alloy coated with graphene oxide/silver nanoparticles via electrophoretic deposition

Scientific Reports ◽

10.1038/s41598-021-92340-7 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Sirapat Pipattanachat ◽

Jiaqian Qin ◽

Dinesh Rokaya ◽

Panida Thanyasrisung ◽

Viritpon Srimaneepong

Keyword(s):

Surface Roughness ◽

Silver Nanoparticles ◽

Graphene Oxide ◽

Electrophoretic Deposition ◽

Biofilm Formation ◽

Niti Alloy ◽

Surface Characteristics ◽

Dependent Manner ◽

Biofilm Inhibition ◽

Coating Time

AbstractBiofilm formation on medical devices can induce complications. Graphene oxide/silver nanoparticles (GO/AgNPs) coated nickel-titanium (NiTi) alloy has been successfully produced. Therefore, the aim of this study was to determine the anti-bacterial and anti-biofilm effects of a GO/AgNPs coated NiTi alloy prepared by Electrophoretic deposition (EPD). GO/AgNPs were coated on NiTi alloy using various coating times. The surface characteristics of the coated NiTi alloy substrates were investigated and its anti-biofilm and anti-bacterial effect on Streptococcus mutans biofilm were determined by measuring the biofilm mass and the number of viable cells using a crystal violet assay and colony counting assay, respectively. The results showed that although the surface roughness increased in a coating time-dependent manner, there was no positive correlation between the surface roughness and the total biofilm mass. However, increased GO/AgNPs deposition produced by the increased coating time significantly reduced the number of viable bacteria in the biofilm (p < 0.05). Therefore, the GO/AgNPs on NiTi alloy have an antibacterial effect on the S. mutans biofilm. However, the increased surface roughness does not influence total biofilm mass formation (p = 0.993). Modifying the NiTi alloy surface using GO/AgNPs can be a promising coating to reduce the consequences of biofilm formation.

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Modeling of surface roughness in a novel magnetorheological gear profile finishing process

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1177/0954406220978265 ◽

2020 ◽

pp. 095440622097826

Author(s):

Ravi Datt Yadav ◽

Anant Kumar Singh ◽

Kunal Arora

Keyword(s):

Surface Roughness ◽

Gear Tooth ◽

Surface Characteristics ◽

Spur Gear ◽

Tooth Profile ◽

Tooth Surface ◽

Magnetic Flux Density ◽

Element Analysis ◽

Finishing Process ◽

Gear Profile

Fine finishing of spur gears reduces the vibrations and noise and upsurges the service life of two mating gears. A new magnetorheological gear profile finishing (MRGPF) process is utilized for the fine finishing of spur gear teeth profile surfaces. In the present study, the development of a theoretical mathematical model for the prediction of change in surface roughness during the MRGPF process is done. The present MRGPF is a controllable process with the magnitude of the magnetic field, therefore, the effect of magnetic flux density (MFD) on the gear tooth profile has been analyzed using an analytical approach. Theoretically calculated MFD is validated experimentally and with the finite element analysis. To understand the finishing process mechanism, the different forces acting on the gear surface has been investigated. For the validation of the present roughness model, three sets of finishing cycle experimentations have been performed on the spur gear profile by the MRGPF process. The surface roughness of the spur gear tooth surface after experimentation was measured using Mitutoyo SJ-400 surftest and is equated with the values of theoretically calculated surface roughness. The results show the close agreement which ranges from −7.69% to 2.85% for the same number of finishing cycles. To study the surface characteristics of the finished spur gear tooth profile surface, scanning electron microscopy is used. The present developed theoretical model for surface roughness during the MRGPF process predicts the finishing performance with cycle time, improvement in the surface quality, and functional application of the gears.

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Effect of Water-Based Nanolubricants in Ultrasonic Vibration Assisted Grinding

Journal of Manufacturing and Materials Processing ◽

10.3390/jmmp2040080 ◽

2018 ◽

Vol 2 (4) ◽

pp. 80 ◽

Cited By ~ 1

Author(s):

Mir Molaie ◽

Ali Zahedi ◽

Javad Akbari

Keyword(s):

Surface Roughness ◽

Specific Energy ◽

Material Removal ◽

Normal Force ◽

Tangential Force ◽

Process Efficiency ◽

Multiwall Carbon Nanotube ◽

Ultrasonic Vibrations ◽

Mql Grinding ◽

Water Based

Currently, because of stricter environmental standards and highly competitive markets, machining operations, as the main part of the manufacturing cycle, need to be rigorously optimized. In order to simultaneously maximize the production quality and minimize the environmental issues related to the grinding process, this research study evaluates the performance of minimum quantity lubrication (MQL) grinding using water-based nanofluids in the presence of horizontal ultrasonic vibrations (UV). In spite of the positive impacts of MQL using nanofluids and UV which are extensively reported in the literature, there is only a handful of studies on concurrent utilization of these two techniques. To this end, for this paper, five kinds of water-based nanofluids including multiwall carbon nanotube (MWCNT), graphite, Al2O3, graphene oxide (GO) nanoparticles, and hybrid Al2O3/graphite were employed as MQL coolants, and the workpiece was oscillated along the feed direction with 21.9 kHz frequency and 10 µm amplitude. Machining forces, specific energy, and surface quality were measured for determining the process efficiency. As specified by experimental results, the variation in the material removal nature made by ultrasonic vibrations resulted in a drastic reduction of the grinding normal force and surface roughness. In addition, the type of nanoparticles dispersed in water had a strong effect on the grinding tangential force. Hybrid Al2O3/graphite nanofluid through two different kinds of lubrication mechanisms—third body and slider layers—generated better lubrication than the other coolants, thereby having the lowest grinding forces and specific energy (40.13 J/mm3). It was also found that chemically exfoliating the graphene layers via oxidation and then purification prior to dispersion in water promoted their effectiveness. In conclusion, UV assisted MQL grinding increases operation efficiency by facilitating the material removal and reducing the use of coolants, frictional losses, and energy consumption in the grinding zone. Improvements up to 52%, 47%, and 61%, respectively, can be achieved in grinding normal force, specific energy, and surface roughness compared with conventional dry grinding.

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Post-Processing and Surface Characterization of Additively Manufactured Stainless Steel 316L Lattice: Implications for BioMedical Use

Materials ◽

10.3390/ma14061376 ◽

2021 ◽

Vol 14 (6) ◽

pp. 1376

Author(s):

Alex Quok An Teo ◽

Lina Yan ◽

Akshay Chaudhari ◽

Gavin Kane O’Neill

Keyword(s):

Surface Roughness ◽

Stainless Steel ◽

Surface Characterization ◽

High Surface ◽

Surface Characteristics ◽

Post Processing ◽

Stainless Steel 316L ◽

Processing Methods ◽

Particulate Debris

Additive manufacturing of stainless steel is becoming increasingly accessible, allowing for the customisation of structure and surface characteristics; there is little guidance for the post-processing of these metals. We carried out this study to ascertain the effects of various combinations of post-processing methods on the surface of an additively manufactured stainless steel 316L lattice. We also characterized the nature of residual surface particles found after these processes via energy-dispersive X-ray spectroscopy. Finally, we measured the surface roughness of the post-processing lattices via digital microscopy. The native lattices had a predictably high surface roughness from partially molten particles. Sandblasting effectively removed this but damaged the surface, introducing a peel-off layer, as well as leaving surface residue from the glass beads used. The addition of either abrasive polishing or electropolishing removed the peel-off layer but introduced other surface deficiencies making it more susceptible to corrosion. Finally, when electropolishing was performed after the above processes, there was a significant reduction in residual surface particles. The constitution of the particulate debris as well as the lattice surface roughness following each post-processing method varied, with potential implications for clinical use. The work provides a good base for future development of post-processing methods for additively manufactured stainless steel.

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Investigation on Surface Grinding of Ti-6Al-4V Using Minimum Quantity Lubrication

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.500.308 ◽

2012 ◽

Vol 500 ◽

pp. 308-313 ◽

Cited By ~ 2

Author(s):

Guo Qiang Guo ◽

Zhi Qiang Liu ◽

Xiao Hu Zheng ◽

Ming Chen

Keyword(s):

Surface Roughness ◽

Plastic Deformation ◽

Surface Morphology ◽

Specific Energy ◽

Minimum Quantity Lubrication ◽

Grinding Force ◽

Dry Grinding ◽

Surface Damages ◽

Side Flow ◽

Mql System

This paper investigates the effects of MQL system on the grinding performance of Ti-6Al-4V using SiC abrasive, the evaluation of the performance consisted of analyzing the grinding force, surface roughness and surface morphology. The experiment result indicated that the favorable lubricating effect of MQL oil makes it has the lowest value of grinding force, specific energy and force raito. MQL has better surface finish than dry grinding and fluid grinding has the lowest value of surface roughness under different grinding depth. Surface damages such as: side flow, plastic deformation, redeposition are present in dry and fluid grinding. As grinding depth increased, the damages become much more severe. But in MQL condition, it gives better surface integrity than dry and fluid grinding.

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Surface Roughness of Two CAD/CAM Restorative Materials as Affected by Chewing Simulation v1

10.17504/protocols.io.b3jiqkke ◽

2022 ◽

Author(s):

eaeldwakhly not provided

Keyword(s):

Surface Roughness ◽

Computer Aided Design ◽

Surface Characteristics ◽

Ceramic Materials ◽

Study Groups ◽

Significance Level ◽

Chewing Simulation ◽

Computer Aided ◽

Cad Cam ◽

The Individual

This study was conducted to assess the surface characteristics in terms of roughness of two CAD/CAM (Computer-Aided-Design/Computer-Aided Manufacturing)restorative material spre and post chewing simulation exposure. Methods: Specimens were prepared from two CAD/CAM ceramic materials: Cerec Blocs C and IPS e-max ZirCAD. A total of 10 disks were prepared for each study group. 3D optical noncontact surface profiler was used to test the surface roughness (ContourGT, Bruker, Campbell, CA, USA). A silicone mold was used to fix the individual samples using a self-curing resin. Surface roughness (SR) was examined pre and post exposure to chewing simulation. 480,000 simulated chewing cycles were conducted to mimic roughly two years of intraoral clinical service. The results data was first tested for normality and equal variance (Levene’s test >0.05) then examined with paired and independent sample t-test at a significance level of (p < 0.05). Results:The two CAD-CAM materials tested exhibited increased surface roughness from baseline. The highest mean surface roughness was observed in Cerec blocs C group after chewing simulation (2.34 µm± 0.62 µm). Whereas the lowest surface roughness was observed in IPS e.max ZirCAD group before chewing simulation (0.42 µm± 0.16 µm). Both study groups exhibited significantly different surface roughness values (p< 0.05). There was a statistically higher surface roughness values after the chewing simulation in Cerec blocs C when compared to IPS e.max ZirCAD groups (p = 0.000).Conclusion:Even though both tested CAD/CAM materials differ in recorded surface roughness values, results were within clinically accepted values.

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Generation mechanism modeling of surface topography in tangential ultrasonic vibration-assisted grinding with green silicon carbide abrasive wheel

Proceedings of the Institution of Mechanical Engineers Part B Journal of Engineering Manufacture ◽

10.1177/09544054211040609 ◽

2021 ◽

pp. 095440542110406

Author(s):

Yutong Qiu ◽

Jingfei Yin ◽

Yang Cao ◽

Wenfeng Ding

Keyword(s):

Surface Roughness ◽

Surface Topography ◽

Ultrasonic Vibration ◽

Generation Mechanism ◽

Surface Generation ◽

Depth Of Cut ◽

Abrasive Wheel ◽

Grinding Parameters ◽

Conventional Grinding ◽

Ultrasonic Vibration Assisted Grinding

Tangential ultrasonic vibration-assisted grinding (TUAG) has a wide prospect in machining difficult-to-machine materials. However, the surface generation mechanism in TUAG is not fully recovered. This study proposes an analytical model of the surface topography produced by TUAG. Based on the model, the surface topography and roughness are predicted and experimentally verified. In addition, the influence of the grinding parameters on the surface topography is analyzed. The predicted surface topography well coincides with experimental measurements, and the prediction error in surface roughness Ra by the proposed model is less than 5%. Compared with conventional grinding, TUAG produces a surface with more uniform scratches and surface roughness Ra was reduced by up to 27% with the proper parameters. However, the improvement of surface roughness in TUAG is weakened when grinding speed or depth of cut increases. Moreover, the influence of the ultrasonic vibration amplitude on the surface roughness is not monotonous. With the grinding parameters selected in this study, TUAG with an ultrasonic amplitude of 7.5 μm produces the minimum surface roughness.

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Mechanisms of Reactive Oxygen Species Generated by Inorganic Nanomaterials for Cancer Therapeutics

Frontiers in Chemistry ◽

10.3389/fchem.2021.630969 ◽

2021 ◽

Vol 9 ◽

Author(s):

Lizhen Zhang ◽

Chengyuan Zhu ◽

Rongtao Huang ◽

Yanwen Ding ◽

Changping Ruan ◽

...

Keyword(s):

Reactive Oxygen Species ◽

Biomedical Applications ◽

Reactive Oxygen ◽

Cancer Therapeutics ◽

Surface Characteristics ◽

Oxygen Species ◽

Sonodynamic Therapy ◽

Dynamic Therapy ◽

Inorganic Nanomaterials ◽

Generation Mechanisms

Recently, inorganic nanomaterials have received considerable attention for use in biomedical applications owing to their unique physicochemical properties based on their shapes, sizes, and surface characteristics. Photodynamic therapy (PDT), sonodynamic therapy (SDT), and chemical dynamic therapy (CDT), which are cancer therapeutics mediated by reactive oxygen species (ROS), have the potential to significantly enhance the therapeutic precision and efficacy for cancer. To facilitate cancer therapeutics, numerous inorganic nanomaterials have been developed to generate ROS. This mini review provides an overview of the generation mechanisms of ROS by representative inorganic nanomaterials for cancer therapeutics, including the structures of engineered inorganic nanomaterials, ROS production conditions, ROS types, and the applications of the inorganic nanomaterials in cancer PDT, SDT, and CDT.

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