{"title":"Dynamic Measurement of a Head-Disk Spacing Variation for High Density FDD","authors":"K. Ajiki;T. Okumura;Y. Hayakawa;A. Hirano","doi":"10.1109/TJMJ.1994.4565923","DOIUrl":"https://doi.org/10.1109/TJMJ.1994.4565923","url":null,"abstract":"A head-disk interface (HDI) analyzer for high-density floppy disk drives (FDDs) was improved. This equipment consists of a high-shutter-speed camera and a highly sensitive image processor. It makes possible the evaluation of dynamic spacing fluctuation by analysis of interference fringe patterns on both sides of a floppy disk (FD). With this equipment, the dynamic motions of an up-head slider and FD were observed. Moreover, it was shown that the surface roughness of the FD affects the head contact and that a smoother disk surface causes larger fluctuations in spacing. This result indicates that a surface of appropriate roughness is required of FDs so as to maintain reliability in high-density FDDs.","PeriodicalId":100647,"journal":{"name":"IEEE Translation Journal on Magnetics in Japan","volume":"9 5","pages":"47-53"},"PeriodicalIF":0.0,"publicationDate":"1994-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1109/TJMJ.1994.4565923","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67892852","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Preparation and Soft Magnetic Properties of Pulse-Plated Permalloy Films","authors":"Y. Omata;H. Asai;T. Shinosaki","doi":"10.1109/TJMJ.1994.4565932","DOIUrl":"https://doi.org/10.1109/TJMJ.1994.4565932","url":null,"abstract":"A method for preparing permalloy films by electrodeposition using a square-wave pulse-mode current was studied, along with the magnetic properties of the resulting films. The influence of three plating parameters (duty cycle ratio, frequency, and dc bias) on the formation of film structures, alloy composition, and magnetic properties was investigated. It was found that films with μ\u0000<sub>i</sub>\u0000≥4000 (max. 6000) and with zero magnetostriction can be obtained with good reproducibility by pulse-plating at a low duty cycle ratio. The characteristics of permalloy film electrodeposited using a square-wave pulse current are discussed.","PeriodicalId":100647,"journal":{"name":"IEEE Translation Journal on Magnetics in Japan","volume":"9 5","pages":"106-111"},"PeriodicalIF":0.0,"publicationDate":"1994-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1109/TJMJ.1994.4565932","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67893973","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Mark Formation Mechanisms and R/W Characteristics for Gd1-xTbxFeCo/TbFe1-yCoy Films","authors":"M. Ogawa;M. Kubogata;O. Okada","doi":"10.1109/TJMJ.1994.4565936","DOIUrl":"https://doi.org/10.1109/TJMJ.1994.4565936","url":null,"abstract":"Mark formation mechanisms and R/W characteristics of two kinds of exchange-coupled magneto-optical disks, consisting of a read layer and a write layer, were investigated using an RAY tester and a polarizing microscope. In one of the disks (a regular-mode disk), marks recorded in the read layer were transcribed to the write layer; the opposite was the case in the other disk (an inverse-mode disk). In the case of the regular-mode disks, the characteristics of the carrier levels in relation to the writing power showed two stages, corresponding to ring domains and full domains. The ring domains appeared when the write power was low, and were caused by the static magnetic field near the T\u0000<inf>c</inf>\u0000 radius in the write layer. The full domains appeared when the write power was high, because the anisotropic field in the reading layer decreased sufficiently. Only one stage was observed in inverse-mode disks. This is because the marks, which were formed by the Curie-point writing process in the write layer, were transcribed to the read layer.","PeriodicalId":100647,"journal":{"name":"IEEE Translation Journal on Magnetics in Japan","volume":"9 5","pages":"132-138"},"PeriodicalIF":0.0,"publicationDate":"1994-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1109/TJMJ.1994.4565936","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67893976","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"[Advertisement]","authors":"","doi":"10.1109/TJMJ.1994.4565942","DOIUrl":"https://doi.org/10.1109/TJMJ.1994.4565942","url":null,"abstract":"Advertisement.","PeriodicalId":100647,"journal":{"name":"IEEE Translation Journal on Magnetics in Japan","volume":"9 5","pages":"nil2-nil2"},"PeriodicalIF":0.0,"publicationDate":"1994-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1109/TJMJ.1994.4565942","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67892837","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Co-Cr Perpendicular Anisotropy Films Sputter-Deposited at Very High Ar Gas Pressures and Low Discharge Voltages","authors":"N. Honda;J. Ariake;K. Ouchi;S. Iwasaki","doi":"10.1109/TJMJ.1994.4565917","DOIUrl":"https://doi.org/10.1109/TJMJ.1994.4565917","url":null,"abstract":"Co-Cr perpendicular magnetic films were sputter-deposited at extraordinarily high Ar gas pressures above 10 Pa at discharge voltages below 300 V. When films were deposited on glass substrates at Ar gas pressures above 10 Pa, they exhibited columnar structures with large grain sizes and poor crystal orientation, together with large squareness of the in-plane M-H loop. When Ti underlayers with a high perpendicular c-axis orientation (Δθ\u0000<sub>50</sub>\u0000≈5°), were introduced, a high crystal orientation (Δθ\u0000<sub>50</sub>\u0000<5°)>r//</sub>\u0000/M\u0000<sub>s</sub>\u0000≈0.2) were obtained for Co-Cr films deposited at 50 Pa. Films 200 nm in thickness showed fine columnar structures with distinct grains about 50 nm in diameter. This type of film is regarded as a possible candidate for high-density perpendicular recording media, achieved using a preparation method with improved discharge characteristics.","PeriodicalId":100647,"journal":{"name":"IEEE Translation Journal on Magnetics in Japan","volume":"9 5","pages":"9-14"},"PeriodicalIF":0.0,"publicationDate":"1994-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1109/TJMJ.1994.4565917","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67892843","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Effect of the Vibration Characteristics of a Head/Disk on Durability","authors":"Y. Ohta;A. Rokugawa;J. Takahashi","doi":"10.1109/TJMJ.1994.4565924","DOIUrl":"https://doi.org/10.1109/TJMJ.1994.4565924","url":null,"abstract":"We investigated the influence of the vibration characteristics of a head/disk system in contact recording. The frequency response function (FRF) and Q factor were used to analyze the vibration of the head-disk interface motion in sliding contact tests. The effect of the natural frequencies of the various disks is examined. The Q factor, obtained from the FRF of the vibration of the head-disk interface motion, is related to the durability in sliding contact tests.","PeriodicalId":100647,"journal":{"name":"IEEE Translation Journal on Magnetics in Japan","volume":"9 5","pages":"54-59"},"PeriodicalIF":0.0,"publicationDate":"1994-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1109/TJMJ.1994.4565924","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67892851","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
K. Ikuma;K. Akioka;T. Shimoda;R. Watanabe;H. Miyadera
{"title":"High-Energy Extrusion-Molded Nd-Fe-B Magnets","authors":"K. Ikuma;K. Akioka;T. Shimoda;R. Watanabe;H. Miyadera","doi":"10.1109/TJMJ.1994.4565930","DOIUrl":"https://doi.org/10.1109/TJMJ.1994.4565930","url":null,"abstract":"High-energy extrusion-molded magnets, composed of isotropic Nd-Fe-B powder and Nylon-12, were developed. The mechanical properties and packing factor of the extruded products were investigated. With proper adjustment of the magnetic powder distribution, the extruded products contained 78 vol% magnetic powder and had a (BH)\u0000<inf>max</inf>\u0000 of 9.9 MGOe. The shearing strength of the extruded products was 7.83 kgf/mm\u0000<sup>2</sup>\u0000, which is about 1.6 times that of compression-molded magnets with the same formulation. The porosity fraction in the extruded products was 1.1%, which is significantly less than in compression-molded magnets.","PeriodicalId":100647,"journal":{"name":"IEEE Translation Journal on Magnetics in Japan","volume":"9 5","pages":"94-99"},"PeriodicalIF":0.0,"publicationDate":"1994-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1109/TJMJ.1994.4565930","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68067463","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"List of contributors","authors":"","doi":"10.1109/TJMJ.1994.4565913","DOIUrl":"https://doi.org/10.1109/TJMJ.1994.4565913","url":null,"abstract":"Contains an entry for each author and co-author included in this issue of the publication.","PeriodicalId":100647,"journal":{"name":"IEEE Translation Journal on Magnetics in Japan","volume":"9 5","pages":"nil1-nil1"},"PeriodicalIF":0.0,"publicationDate":"1994-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1109/TJMJ.1994.4565913","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67893977","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Changes in the Magneto-Optical Spectra of Ni3Fe Films Caused by Heat Treatment","authors":"T. Sato;T. Miyahara;T. Miyazaki","doi":"10.1109/TJMJ.1994.4565940","DOIUrl":"https://doi.org/10.1109/TJMJ.1994.4565940","url":null,"abstract":"The magnetooptic spectra (σ\u0000<sub>xx</sub>\u0000 and ωσ\u0000<sub>xy</sub>\u0000) of Ni\u0000<sub>3</sub>\u0000Fe thin films before and after heat treatment were investigated in the photon energy range from 1.2 eV to 4.6 eV. It was found that both spectra changed dramatically as a result of heat treatment. The σ\u0000<sub>xx</sub>\u0000 and ωσ\u0000<sub>xy</sub>\u0000 spectra of Ni\u0000<sub>3</sub>\u0000Fe thin films were reduced by the transition from disorder to order. The joint density of states for both ordered and disordered states of Ni\u0000<sub>3</sub>\u0000Fe were also calculated, and were compared with experimental data.","PeriodicalId":100647,"journal":{"name":"IEEE Translation Journal on Magnetics in Japan","volume":"9 5","pages":"158-162"},"PeriodicalIF":0.0,"publicationDate":"1994-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1109/TJMJ.1994.4565940","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67892839","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Unrecorded Areas on Tracks Recorded by Laminated Heads","authors":"H. Kobayashi;M. Ura;T. Ozeki","doi":"10.1109/TJMJ.1994.4565918","DOIUrl":"https://doi.org/10.1109/TJMJ.1994.4565918","url":null,"abstract":"The influence of insulating layers in laminated heads on the head recording pattern was investigated, using the Bitter method and computer simulations. Some unrecorded areas exist on recorded tracks, and these correspond to the positions of insulating areas on the trailing side. An unrecorded area becomes wider as the magnetomotive force is increased. The size of an unrecorded area depends on the insulator thickness and the media coercive force. These results were confirmed by simulations using the finite element method.","PeriodicalId":100647,"journal":{"name":"IEEE Translation Journal on Magnetics in Japan","volume":"9 5","pages":"15-20"},"PeriodicalIF":0.0,"publicationDate":"1994-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1109/TJMJ.1994.4565918","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67892846","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}