Pole Tip Recession: Investigation of Factors Affecting Its Measurement and Its Variation With Contact Start-Stop and Constant Speed Drag Testing

1995 ◽  
Vol 117 (4) ◽  
pp. 580-587 ◽  
Author(s):  
Chandrasekhar Nadimpalli ◽  
Frank E. Talke ◽  
Martin Smallen ◽  
Jerry J. K. Lee
Keyword(s):  
Dissimilar Materials ◽  
Optical Interferometry ◽  
Constant Speed ◽  
Bearing Surface ◽  
Contact Mode ◽  
Factors Affecting ◽  
Force Microscopy ◽  
Atomic Force ◽  
Pole Tip Recession ◽  
Local Value

Optical interferometry and contact mode atomic force microscopy are used to investigate the various factors that influence the measurement of pole tip recession. These factors include: (a) effect of dissimilar materials on optical interferometry results, (b) size and location of the air bearing surface used as the reference area, (c) the effect of slider crown, (d) the magnification of the objective used in optical interferometry and (e) the dependence of the AFM measurements on slider materials and scan direction of the AFM tip. The possibility of determining a local value of pole tip recession is examined wherein the sputtered alumina, rather than the Al2O3-TiC surface, is used as the reference surface. Finally, the effect of contact start/stop (CSS) and constant speed drag testing on pole tip recession is investigated by measuring the change in pole tip recession as a function of the number of start/stop and constant speed drag cycles.

Study of Generation Mechanism of Three-Body Particles in Linear Tape Recording

2005 ◽  
Vol 127 (1) ◽  
pp. 155-163 ◽  
Author(s):  
Baogui Shi ◽  
J. L. Sullivan ◽  
M. A. Wild ◽  
S. O. Saied
Keyword(s):  
Photoelectron Spectroscopy ◽  
Tape Recording ◽  
Bearing Surface ◽  
Abrasive Particles ◽  
Force Microscopy ◽  
Atomic Force ◽  
Magnetic Spacing ◽  
Data Tape ◽  
Three Body ◽  
Pole Tip Recession

A major cause of magnetic spacing losses in data tape systems is pole tip recession (PTR). This study is an investigation of PTR in a linear data tape recording system and identification of the mechanisms responsible for these effects, but the results have implications for any head where the tape bearing surface is Al2O3/TiC, AlTiC. Tape cycling experiments were performed using the linear tape open system as the experimental platform with metal particle tape. All experiments were conducted within a matrix of pressure and humidity, which encompassed the system operating extremes. Atomic force microscopy was used to analyze the surface topography of the heads. Auger electron spectroscopy and x-ray photoelectron spectroscopy were employed to analyze the chemical changes on the surface of the heads and tapes. Environment was found to have a significant influence on the head/tape interface. Head wear and PTR was highest at high temperature and humidity. Water vapor was found to transform the surface layers on the TiC grains in the tape-bearing surface to TiO2. This process results in the production of TiO2 fragments that become trapped in the recessed pole tip region, acting as three-body abrasive particles. The TiO2 present on the TiC grains and on the surface of heads increases with the water content after cycling against tapes. The hypothesis is supported by the presence of Ti on the poles.

Pole Tip Recession Measurements on Thin Film Heads Using Optical Profilometry With Phase Correction and Atomic Force Microscopy

1993 ◽  
Vol 115 (3) ◽  
pp. 382-386 ◽  
Author(s):  
Martin Smallen ◽  
Jerry J. K. Lee
Keyword(s):  
Thin Film ◽  
Atomic Force Microscopy ◽  
Magnetic Recording ◽  
Dissimilar Materials ◽  
Optical Measurements ◽  
Optical Profilometry ◽  
Force Microscopy ◽  
Atomic Force ◽  
Analytical Correction ◽  
Pole Tip Recession

Pole tip recession in magnetic recording thin film heads contributes to spacing loss, which leads to a degradation in the readback signal. As manufacturers improve the performance of magnetic recording devices, this recession will become more significant to the performance of future products. Pole tip recession can be measured by several techniques, including stylus profilometry, optical profilometry, and atomic force microscopy. Stylus profilometry is generally not used since it has several problems in this application. In this study, good correlation was found between optical profilometry and atomic force microscopy measurements, provided that the optical measurements were corrected for phase shift. This is necessary because of the dissimilar materials in the thin film head. There are several methods for making this correction. One method is an analytical correction using known optical constants for the head materials. These constants should be well characterized as the measurements are quite sensitive to them. Overcoating the head with a thin film provides two other methods for getting around the material differences problem. However, these methods require an optimum film thickness. The film must be thick enough so that it behaves as a substrate, but not so thick that it fails to replicate the head. PACS numbers: 85.70.Kh, 06.90. + v, 42.72. + h, 78.65.Pi

Surface roughness measurements of vanadium-contaminated fluidized cracking catalysts by atomic force microscopy

1996 ◽  
Vol 54 ◽  
pp. 866-867
Author(s):  
H. Kinney ◽  
M.L. Occelli ◽  
S.A.C. Gould
Keyword(s):  
Surface Roughness ◽  
Zeolite Y ◽  
Atomic Level ◽  
Microporous Structure ◽  
Contact Mode ◽  
Force Microscopy ◽  
Atomic Force ◽  
Before And After ◽  
Roughness Measurements ◽  
Cracking Catalysts

For this study we have used a contact mode atomic force microscope (AFM) to study to topography of fluidized cracking catalysts (FCC), before and after contamination with 5% vanadium. We selected the AFM because of its ability to well characterize the surface roughness of materials down to the atomic level. It is believed that the cracking in the FCCs occurs mainly on the catalysts top 10-15 μm suggesting that the surface corrugation could play a key role in the FCCs microactivity properties. To test this hypothesis, we chose vanadium as a contaminate because this metal is capable of irreversibly destroying the FCC crystallinity as well as it microporous structure. In addition, we wanted to examine the extent to which steaming affects the vanadium contaminated FCC. Using the AFM, we measured the surface roughness of FCCs, before and after contamination and after steaming.We obtained our FCC (GRZ-1) from Davison. The FCC is generated so that it contains and estimated 35% rare earth exchaged zeolite Y, 50% kaolin and 15% binder.

scholarly journals Dynamic friction energy dissipation and enhanced contrast in high frequency bimodal atomic force microscopy

Friction ◽  
2021 ◽  
Author(s):  
Xinfeng Tan ◽  
Dan Guo ◽  
Jianbin Luo
Keyword(s):  
Atomic Force Microscopy ◽  
Energy Dissipation ◽  
Contact Friction ◽  
Measuring Instruments ◽  
Dynamic Friction ◽  
Contact Mode ◽  
Force Microscopy ◽  
Atomic Force ◽  
Friction Energy ◽  
New Applications

AbstractDynamic friction occurs not only between two contact objects sliding against each other, but also between two relative sliding surfaces several nanometres apart. Many emerging micro- and nano-mechanical systems that promise new applications in sensors or information technology may suffer or benefit from noncontact friction. Herein we demonstrate the distance-dependent friction energy dissipation between the tip and the heterogeneous polymers by the bimodal atomic force microscopy (AFM) method driving the second order flexural and the first order torsional vibration simultaneously. The pull-in problem caused by the attractive force is avoided, and the friction dissipation can be imaged near the surface. The friction dissipation coefficient concept is proposed and three different contact states are determined from phase and energy dissipation curves. Image contrast is enhanced in the intermediate setpoint region. The work offers an effective method for directly detecting the friction dissipation and high resolution images, which overcomes the disadvantages of existing methods such as contact mode AFM or other contact friction and wear measuring instruments.

scholarly journals Atomic force microscopy comparative analysis of the surface roughness of two posterior chamber phakic intraocular lens models: ICL versus IPCL

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Juan Gros-Otero ◽  
Samira Ketabi ◽  
Rafael Cañones-Zafra ◽  
Montserrat Garcia-Gonzalez ◽  
Cesar Villa-Collar ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Atomic Force Microscopy ◽  
Intraocular Lenses ◽  
Posterior Chamber ◽  
Anterior Surface ◽  
Contact Mode ◽  
Force Microscopy ◽  
Atomic Force ◽  
Phakic Intraocular Lenses ◽  
Roughness Measurements

Abstract Background To compare the anterior surface roughness of two commercially available posterior chamber phakic intraocular lenses (IOLs) using atomic force microscopy (AFM). Methods Four phakic IOLs were used for this prospective, experimental study: two Visian ICL EVO+ V5 lenses and two iPCL 2.0 lenses. All of them were brand new, were not previously implanted in humans, were monofocal and had a dioptric power of − 12 diopters (D). The anterior surface roughness was assessed using a JPK NanoWizard II® atomic force microscope in contact mode immersed in liquid. Olympus OMCL-RC800PSA commercial silicon nitride cantilever tips were used. Anterior surface roughness measurements were made in 7 areas of 10 × 10 μm at 512 × 512 point resolution. The roughness was measured using the root-mean-square (RMS) value within the given regions. Results The mean of all anterior surface roughness measurements was 6.09 ± 1.33 nm (nm) in the Visian ICL EVO+ V5 and 3.49 ± 0.41 nm in the iPCL 2.0 (p = 0.001). Conclusion In the current study, we found a statistically significant smoother anterior surface in the iPCL 2.0 phakic intraocular lenses compared with the VISIAN ICL EVO+ V5 lenses when studied with atomic force microscopy.

Contact and non-contact mode imaging by atomic force microscopy

1996 ◽  
Vol 273 (1-2) ◽  
pp. 138-142 ◽  
Author(s):  
Seizo Morita ◽  
Satoru Fujisawa ◽  
Eigo Kishi ◽  
Masahiro Ohta ◽  
Hitoshi Ueyama ◽  
...  
Keyword(s):  
Atomic Force Microscopy ◽  
Contact Mode ◽  
Force Microscopy ◽  
Atomic Force

Conducting Polymer nanoComposites (CPC): Nanocharacterisation of layer by layer sprayed PMMA-CNT vapour sensors by Atomic force Microscopy in current Sensing Mode (CS-AFM)

2008 ◽  
Vol 1143 ◽  
Author(s):  
Bijandra Kumar ◽  
Mickaël Castro ◽  
Jianbo Lu ◽  
Jean-François Feller
Keyword(s):  
Atomic Force Microscopy ◽  
Spray Deposition ◽  
Dynamic Mode ◽  
Layer By Layer ◽  
Initial State ◽  
Contact Mode ◽  
Current Sensing ◽  
Multi Wall Carbon Nanotubes ◽  
Force Microscopy ◽  
Atomic Force

ABSTRACTOrganic vapour sensors based on poly (methylmethacrylate)-multi-wall carbon nanotubes (PMMA-CNT) conductive polymer nanocomposite (CPC) were developed via layer by layer technique by spray deposition. CPC Sensors were exposed to three different classes of solvents (chloroform, methanol and water) and their chemo-electrical properties were followed as a function of CNTcontent in dynamic mode. Detection time was found to be shorter than that necessary for full recovery of initial state. CNT real three dimensional network has been visualized by Atomic force microscopy in a field assisted intermittent contact mode. More interestingly real conductive network system and electrical ability of CPC have been explored by current-sensing atomic force microscopy (CS-AFM). Realistic effect of voltage on electrical conductivity has been found linear.

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