Analysis of tape surface roughness by magnetic recording and mechanical methods

2000 ◽  
Vol 36 (1) ◽  
pp. 189-194 ◽  
Author(s):  
Peng Luo ◽  
Sanwu Tan ◽  
H.N. Bertram ◽  
G. Hughes ◽  
F.E. Talke
Keyword(s):  
Surface Roughness ◽  
Magnetic Recording ◽  
Mechanical Methods

scholarly journals Micromachining of Transparent Biocompatible Polymers Applied in Medicine Using Bursts of Femtosecond Laser Pulses

Micromachines ◽  
2020 ◽  
Vol 11 (12) ◽  
pp. 1093
Author(s):  
Evaldas Kažukauskas ◽  
Simas Butkus ◽  
Piotr Tokarski ◽  
Vytautas Jukna ◽  
Martynas Barkauskas ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Femtosecond Laser ◽  
Contact Lenses ◽  
Laser Pulses ◽  
Laser Micromachining ◽  
Femtosecond Laser Pulses ◽  
Intraocular Lenses ◽  
Great Promise ◽  
Biocompatible Polymers ◽  
Mechanical Methods

Biocompatible polymers are used for many different purposes (catheters, artificial heart components, dentistry products, etc.). An important field for biocompatible polymers is the production of vision implants known as intraocular lenses or custom-shape contact lenses. Typically, curved surfaces are manufactured by mechanical means such as milling, turning or lathe cutting. The 2.5 D objects/surfaces can also be manufactured by means of laser micromachining; however, due to the nature of light–matter interaction, it is difficult to produce a surface finish with surface roughness values lower than ~1 µm Ra. Therefore, laser micromachining alone can’t produce the final parts with optical-grade quality. Laser machined surfaces may be polished via mechanical methods; however, the process may take up to several days, which makes the production of implants economically challenging. The aim of this study is the investigation of the polishing capabilities of rough (~1 µm Ra) hydrophilic acrylic surfaces using bursts of femtosecond laser pulses. By changing different laser parameters, it was possible to find a regime where the surface roughness can be minimized to 18 nm Ra, while the polishing of the entire part takes a matter of seconds. The produced surface demonstrates a transparent appearance and the process shows great promise towards commercial fabrication of low surface roughness custom-shape optics.

Tribology of Solid Contacts in Magnetic Recording Devices

1994 ◽  
Vol 47 (6S) ◽  
pp. S199-S203 ◽  
Author(s):  
Bharat Bhushan
Keyword(s):  
Surface Roughness ◽  
Magnetic Recording ◽  
Friction And Wear ◽  
High Reliability ◽  
High Surface ◽  
Operating Conditions ◽  
Magnetic Storage ◽  
Storage Devices ◽  
Close Proximity ◽  
Magnetic Storage Devices

The demand for close proximity of magnetic head to the medium during operation of magnetic recording devices, high surface smoothness, and high reliability requires that friction and wear of the head-medium interface be minimized. Friction and wear are minimized by suitable selection of interface materials and lubricants, optimization of surface roughness, and operating conditions. This invited paper presents the state of the art of the characterization of surface roughness and modelling of dry and wet solid contacts which are critical to the design of the modern magnetic storage devices.

scholarly journals Adverse Effects on PMMA Caused by Mechanical and Combined Methods of Denture Cleansing

2015 ◽  
Vol 26 (3) ◽  
pp. 292-296 ◽  
Author(s):  
Danilo Balero Sorgini ◽  
Cláudia Helena da Silva-Lovato ◽  
Valdir Antônio Muglia ◽  
Raphael Freitas de Souza ◽  
Carolina Noronha Ferraz de Arruda ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Mass Loss ◽  
Combined Method ◽  
Water Control ◽  
Mechanical Method ◽  
Mechanical Methods ◽  
Significant Difference ◽  
Bonferroni Test ◽  
One Year ◽  
Combined Methods

This study evaluated the abrasiveness of mechanical and combined methods of denture hygiene, by the analysis of mass loss and surface roughness. Acrylic resin specimens (Plexiglass) were brushed by a tooth brushing machine (Mavtec) with a soft brush (Tek) and water (control) or four dentifrices (Sorriso, Colgate, Polident and Corega) (Experimental groups) for 50 min, representing one year of brushing (mechanical method). After brushing, the specimens were immersed in 0.5% sodium hypochlorite simulating a daily cleaning of 20 min for one year (combined method). Distilled water (23 ºC) was employed as control. The mass loss (g) was analyzed by an analytical balance and the surface roughness (μm) by a rugosimeter. Data were subjected to ANOVA and Bonferroni test (α=0.05). Polident dentifrice showed lowest values of mass loss for both methods (mechanical: -0.0072±0.0017, combined:-0.011±0.002) and the combined method resulted in greater mass loss than the mechanical, except for Corega. For the surface roughness, after the mechanical method, the lowest values were registered for water (-0.007±0.016) and Polident (0.402±0.378); for the combined method, water (-0.063±0.013) showed the lowest values; there was no statistically significant difference between methods. It was concluded that Polident was the less abrasive dentifrice and the association between chemical and mechanical methods increased the mass loss but did not change the surface roughness of specimens.

scholarly journals Effect of denture cleansers on metal ion release and surface roughness of denture base materials

2012 ◽  
Vol 23 (4) ◽  
pp. 387-393 ◽  
Author(s):  
Letícia Resende Davi ◽  
Daniela Nair Borges Felipucci ◽  
Raphael Freitas de Souza ◽  
Osvaldo Luiz Bezzon ◽  
Cláudia Helena Lovato-Silva ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Metal Ion ◽  
Pure Titanium ◽  
Acrylic Resin ◽  
Commercially Pure Titanium ◽  
Ion Release ◽  
Nickel Chromium ◽  
Commercially Pure ◽  
Metal Ion Release ◽  
Mechanical Methods

Chemical disinfectants are usually associated with mechanical methods to remove stains and reduce biofilm formation. This study evaluated the effect of disinfectants on release of metal ions and surface roughness of commercially pure titanium, metal alloys, and heat-polymerized acrylic resin, simulating 180 immersion trials. Disk-shaped specimens were fabricated with commercially pure titanium (Tritan), nickel-chromium-molybdenum-titanium (Vi-Star), nickel-chromium (Fit Cast-SB Plus), and nickel-chromium-beryllium (Fit Cast-V) alloys. Each cast disk was invested in the flasks, incorporating the metal disk to the heat-polymerized acrylic resin. The specimens (n=5) were immersed in these solutions: sodium hypochlorite 0.05%, Periogard, Cepacol, Corega Tabs, Medical Interporous, and Polident. Deionized water was used as a control. The quantitative analysis of metal ion release was performed using inductively coupled plasma mass spectrometry (ELAN DRC II). A surface analyzer (Surftest SJ-201P) was used to measure the surface roughness (µm). Data were recorded before and after the immersions and evaluated by two-way ANOVA and Tukey's test (α=0.05). The nickel release proved most significant with the Vi-Star and Fit Cast-V alloys after immersion in Medical Interporous. There was a significant difference in surface roughness of the resin (p=0.011) after immersion. Cepacol caused significantly higher resin roughness. The immersion products had no influence on metal roughness (p=0.388). It could be concluded that the tested alloys can be considered safe for removable denture fabrication, but disinfectant solutions as Cepacol and Medical Interporous tablet for daily denture immersion should be used with caution because it caused greater resin surface roughness and greater ion release, respectively.

Sign in / Sign up

Export Citation Format

Share Document