Tribological Performance of the Head-Disk Interface in Perpendicular Magnetic Recording and Heat-Assisted Magnetic Recording PDF Download
Are you looking for read ebook online? Search for your book and save it on your Kindle device, PC, phones or tablets. Download Tribological Performance of the Head-Disk Interface in Perpendicular Magnetic Recording and Heat-Assisted Magnetic Recording PDF full book. Access full book title Tribological Performance of the Head-Disk Interface in Perpendicular Magnetic Recording and Heat-Assisted Magnetic Recording by Tan Duy Trinh. Download full books in PDF and EPUB format.
Author: Tan Duy Trinh Publisher: ISBN: Category : Languages : en Pages : 185
Book Description
International Data Corporation (IDC) estimates that hard disk drives will still be the main storage device for storing digital data in the next 10 years, holding approximately 80% of the data inside data centers. To increase the areal density of hard disk drives, the mechanical spacing between the head and disk surface has decreased to approximately 1nm. At such a small spacing, tribology of the head-disk interface, including head-disk contacts, wear, material buildup, and lubricant transfer, become increasingly more important for the reliability of hard disk drives. In addition to small spacing, heat-assisted magnetic recording (HAMR) technology aims to deliver higher areal density recording by heating up the media surface to a few hundred Celsius degrees, facilitating the writing process. High temperature at the head and disk surfaces cause serious reliability issues for the head-disk interface (HDI). Therefore, understanding of the main factors that affect the reliability of the head-disk interface is an essential task. In this dissertation, the effect of bias voltage and helium environment on the tribological performance of the head-disk interface is investigated. To do this, we first simulated the flying characteristics of the slider as a function of bias voltage in air and helium environment. Thereafter, an experimental study was performed using custom built tester located inside a sealed environmental chamber to study the effect of air and helium on wear and lubricant redistribution at the head-disk interface during load-unload. We investigated the effect of bias voltage and relative humidity on wear, material buildup, and nano-corrosion on the slider surface. Finally, we have studied laser current and laser optical power in heat-assisted magnetic recording as a function of operating radius, head-disk clearance, media design, and their effects on the life-time of the head-disk interface. The results of this dissertation provide guidance for the effect of bias voltage, relative humidity, and helium environment on wear, material buildup, corrosion, and lubricant transfer at the head-disk interface. More importantly, our experimental study in heat-assisted magnetic recording leads to a better understanding of the main factors that cause failure of the HAMR head-disk interface. Our results are important for the improvement of the tribological performance and reliability of perpendicular magnetic recording (PMR) and heat-assisted magnetic recording (HAMR) head-disk interface.
Author: Tan Duy Trinh Publisher: ISBN: Category : Languages : en Pages : 185
Book Description
International Data Corporation (IDC) estimates that hard disk drives will still be the main storage device for storing digital data in the next 10 years, holding approximately 80% of the data inside data centers. To increase the areal density of hard disk drives, the mechanical spacing between the head and disk surface has decreased to approximately 1nm. At such a small spacing, tribology of the head-disk interface, including head-disk contacts, wear, material buildup, and lubricant transfer, become increasingly more important for the reliability of hard disk drives. In addition to small spacing, heat-assisted magnetic recording (HAMR) technology aims to deliver higher areal density recording by heating up the media surface to a few hundred Celsius degrees, facilitating the writing process. High temperature at the head and disk surfaces cause serious reliability issues for the head-disk interface (HDI). Therefore, understanding of the main factors that affect the reliability of the head-disk interface is an essential task. In this dissertation, the effect of bias voltage and helium environment on the tribological performance of the head-disk interface is investigated. To do this, we first simulated the flying characteristics of the slider as a function of bias voltage in air and helium environment. Thereafter, an experimental study was performed using custom built tester located inside a sealed environmental chamber to study the effect of air and helium on wear and lubricant redistribution at the head-disk interface during load-unload. We investigated the effect of bias voltage and relative humidity on wear, material buildup, and nano-corrosion on the slider surface. Finally, we have studied laser current and laser optical power in heat-assisted magnetic recording as a function of operating radius, head-disk clearance, media design, and their effects on the life-time of the head-disk interface. The results of this dissertation provide guidance for the effect of bias voltage, relative humidity, and helium environment on wear, material buildup, corrosion, and lubricant transfer at the head-disk interface. More importantly, our experimental study in heat-assisted magnetic recording leads to a better understanding of the main factors that cause failure of the HAMR head-disk interface. Our results are important for the improvement of the tribological performance and reliability of perpendicular magnetic recording (PMR) and heat-assisted magnetic recording (HAMR) head-disk interface.
Author: Bharat Bhushan Publisher: Springer Science & Business Media ISBN: 1468403354 Category : Technology & Engineering Languages : en Pages : 1035
Book Description
Magnetic recording is presently a $50 billion industry. It spans audio, video, and digi tal applications in the form of tapes and disks. The industry is expected to grow by a factor of five or more in the next decade. This growth will be accompanied by dramatic improvements in the technology, and the potential exists for magnetic-recording den sities to improve by at least one order of magnitude! Magnetic-recording process is accomplished by relative motion between a mag netic head and a magnetic medium. Types of magnetic media for digital recording are: flexible media (tapes and floppy disks) and rigid disks. Physical contact between head and medium occurs during starts and stops and hydrodynamic air film develops at high speeds. Hying heights (mean separation between head and medium) are on the order of 0. 1 micrometer comparable to surface roughness of the mating members. Need for higher and higher recording densities requires that surfaces be as smooth as possible and flying heights be as low as possible. Smoother surfaces lead to increased static/ kinetic friction and wear. In the case of magnetic tapes, in order to have high bit capac ity for a given size of a spool, we like to use as thin a tape substrate as possible. Thinner tapes are prone to local or bulk viscoelastic deformation during storage. This may lead to variations in head-tape separations resulting in problems in data reliability.
Author: Sakhrat Khizroev Publisher: Springer Science & Business Media ISBN: 1402027230 Category : Technology & Engineering Languages : en Pages : 183
Book Description
Magnetic recording is expected to become core technology in a multi-billion dollar industry in the in the very near future. Some of the most critical discoveries regarding perpendicular write and playback heads and perpendicular media were made only during the last several years as a result of extensive and intensive research in both academia and industry in their fierce race to extend the superparamagnetic limit in the magnetic recording media. These discoveries appear to be critical for implementing perpendicular magnetic recording into an actual disk drive. This book addresses all the open questions and issues which need to be resolved before perpendicular recording can finally be implemented successfully, and is the first monograph in many years to address this subject. This book is intended for graduate students, young engineers and even senior and more experienced researchers in this field who need to acquire adequate knowledge of the physics of perpendicular magnetic recording in order to further develop the field of perpendicular recording.
Author: M.L. Plumer Publisher: Springer Science & Business Media ISBN: 364256657X Category : Science Languages : en Pages : 364
Book Description
Application-oriented book on magnetic recording, focussing on the underlying physical mechanisms that play crucial roles in medium and transducer development for high areal density disk drives.
Author: K.H.J Buschow Publisher: Springer Science & Business Media ISBN: 9401116369 Category : Science Languages : en Pages : 600
Book Description
High density digital magnetic and magneto-optical storage devices are widely used in audio, video, and data processing information technology, as well as in CAD/CAM computer systems. These widespread uses generate a continually increasing demand for both increased information storage densities and capacities, and for reduced access times. Hence, the materials engineering of high density storage media, with a high signal to noise ratio, and the associated design of sophisticated read and write heads, form the basis of major technological research. This research is especially complex because, ideally, the recorded information should be both erasable and, at the same time, secure and accessible over periods of many decades. As a result, research on these complex problems requires a multidisciplinary approach which utilizes the expertise in such widely differing fields as organic, inorganic, and solid state chemistry, metallurgy, solid state physics, electrical and mechanical engineering, and systems analysis. Often, further research specialization is necessary in each of these different disciplines. For instance, solid state physics and chemistry address the problems of crystallographic structure and phase diagram determination, magnetism, and optics, but more advanced research methods, such as high resolution electron microscopy and electronic band structure calculations, are necessary to understand the microstructure of particulate recording media or the electronic spectra of magneto-optical recording media.
Author: Gaspare Varvaro Publisher: CRC Press ISBN: 9814669598 Category : Science Languages : en Pages : 528
Book Description
Today magnetic recording is still the leading technology for mass data storage. Its dominant role is being reinforced by the success of cloud computing, which requires storing and managing huge amounts of data on a multitude of servers. Nonetheless, the hard-disk storage industry is presently at a crossroads as the current magnetic recording techno
Author: Liane M. Matthes Publisher: ISBN: Category : Languages : en Pages : 252
Book Description
Since the introduction of the IBM 305 RAMAC system in 1956, performance and storage capacities of hard disk drives have improved tremendously. To reliably read and write data, the slider must follow the data stored on the magnetic disk closely enough while maintaining a near constant spacing. Currently, the spacing between the recording and the magnetic disk--the flying height--is on the order of 1-2 nm during reading and writing. At such low spacings, intermittent contacts are inevitable, giving rise to wear and degradation of the head-disk interface. Flying heights of 1-2 nm are achieved using thermal flying height control (TFC) technology. TFC recording heads, or TFC sliders, feature thin-film resistive heater elements near the read and write element. Actuating the heater element heats up the nearby material. The material expands due to the heat which causes the slider to (thermally) protrude towards the disk at the location of the read and write element. An increase in heater power increases this protrusion, thus locally reducing the slider flying height. In this dissertation, we focus on experimental investigations of the interface between a TFC slider and a magnetic disk from both a tribological and controls point of view. First, contact and temperature rise between thermal flying height control (TFC) sliders and magnetic disks are studied. Head-disk contact is established by gradually increasing the power input to the resistive heater element of a TFC slider. Laser Doppler vibrometry is employed for studying the dynamics of the vertical gimbal velocity. The gimbal is part of the suspension which the slider is attached to. The temperature rise upon head-disk contact is estimated from the resistance change at the read element via auxiliary calibration measurements. Next, wear of TFC sliders is studied. Head wear was determined by measuring the change in the heater touch-down power before and after wear testing. The touch-down power denotes the power input to the heater of a TFC slider at which the onset of slider-disk contact occurs. After wear testing, selected heads were examined using scanning electron microscopy to identify regions of wear on the write shields. Furthermore, atomic force microscopy images of worn and unworn recording heads were acquired to determine changes in surface roughness. The effect of bonded fraction of the lubricant, relative humidity, and temperature on head wear is investigated. In addition, we study head wear as a function of relative humidity and DC bias voltage applied across the head-disk interface. Wear tests were performed at
Author: Finn Jorgensen Publisher: TAB/Electronics ISBN: Category : Computers Languages : en Pages : 842
Book Description
The Complete Book of Magnetic Recording Get the very latest and most up-to-date information on every aspect of magnetic recording with the 4th edition of one of TAB's all-time best-sellers. Often referred to as the "Bible" by technicians and engineers working in the magnetic recording industry, the Handbook is practical rather than theoretical in its approach. In the rapidly growing field of magnetic recording, this book is truly the "authority" with easy access to topics of interest and extensive instruction on the equipment and techniques prevalent in the industry. This massive reference volume contains numerous illustrations and three indexes (illustrations, names and terms) for quick cross-referencing. References are also included for further study. Every engineer and technician working in the field of magnetic recording should add the Handbook to their reference shelf.
Author: C. Denis Mee Publisher: McGraw Hill Professional ISBN: 9780070412767 Category : Computers Languages : en Pages : 712
Book Description
"This book is concerned with establishing the underlying technologies that are common to all forms of magnetic recording ... adaptable to a wide variety of data, video, and audio applications, both at the business and consumer levels."--Preface, p.xv.
Author: Tan Duy Trinh
Author: Tan Duy Trinh
Author: Shaomin Xiong
Author: Bharat Bhushan
Author: Sakhrat Khizroev
Author: M.L. Plumer
Author: K.H.J Buschow
Author: Gaspare Varvaro
Author: Liane M. Matthes
Author: Finn Jorgensen
Author: C. Denis Mee