• Journal of Sensor Science and Technology
• /
• v.24 no.3
• /
• pp.194-201
• /
• 2015

The current sensor is used in industrial devices and power utilities. Core materials of these current sensors are divided into mainly two groups as silicon steel and fermalloy. Silicon steel has a wide saturation bandwidth but low sensitivity during low-current, whereas permalloy has a short saturation bandwidth but high sensitivity during low-current. In this paper, laminated silicon steel and permalloy by equal ratio is proposed to improve the linearity and saturation of current sensor. It is proved that the proposed core material has larger bandwidth than fermalloy as well as higher sensitivity than silicon steel. When comparing simulation results by FLUX 3D, the proposed method has also better performance than the previous core materials.

• 제어로봇시스템학회:학술대회논문집
• /
• 2003.10a
• /
• pp.1323-1326
• /
• 2003

In this paper, we propose set-up model of silicon steel cold rolling mill. Until now, the working of Silicon Steel is operated using the look-up table value of roll force which a field operator finds by making good use of his experience. Therefore, the standardization of data and an improvement of the quality on product are very difficult. So we establish neural model using field data of various kinds of coil at each pass.

• Journal of the Korean institute of surface engineering
• /
• v.32 no.2
• /
• pp.134-143
• /
• 1999

The effects of silicon on galvannealing behavior of interstitial-free (IF) steels were studied. The growth rate of the Fe-Zn alloy layer was retarded as silicon in the steel added. Titanium in steel strongly favors Fe-Zn reaction, in particular outburst structures, whereas silicon inhibit them. Cross-sectional and planar views of galvannealed coatings were investigated to characterize alloy phase development. A possible mechanism to explain the retardation effect of silicon is discussed in terms of concentration on surface and inhibition layer.

• Journal of the Korean Society for Precision Engineering
• /
• v.14 no.6
• /
• pp.37-43
• /
• 1997

The technology of Laser lamination joining of silicon steel sheets has been studied in this paper. Conventional sheets lamination process does not meet the requirments for the improvement electric parts performance. In response to this, a new Laser spot joining method has been developed. This study performs the Laser spot lamination joining while synchronizing the sillicon steel sheets in the dies with the press movement. Several conclusions have been drawn in this paper. Effects of beam focus, power, atmosphere gas and press oil etc.

• Journal of Korea Foundry Society
• /
• v.25 no.4
• /
• pp.161-167
• /
• 2005

The experiment of hot dip interaction tests was carried out in order to study the formation behavior of interfacial reaction layer between as-received STD61 hot work tool steel and a commercial pure aluminum melt, Al-xwt.%Fe(x=0.2, 0.5, 0.8 and 1.1) alloys melt and Al-xwt.%Si(x=1.0, 4.0, 7.0 and 10.0) alloys melt, respectively. The results show that the reaction layer, over 300 ${\mu}m$ in thickness, is easily formed by the dissolution of silicon from as-received tool steel. When the iron content in the aluminum alloy is higher than 1.1 wt.%, the thickness of reaction layer decreases below 180 ${\mu}m$ by preventing iron dissolution from the tool steel. The silicon dissolved from tool steel acts as a strong promoter on the formation of reaction layer, but the alloyed silicon in molten aluminum alloys acts as an inhibitor on the formation of reaction layer.

• Journal of Magnetics
• /
• v.21 no.2
• /
• pp.209-214
• /
• 2016

This paper analyzes the magnetic property according to the machined shape of steel material with non-oriented silicon steel (50PN470/50A470), that is most commonly used in the design of electrical equipment. Toward this end, specimens were produced and divided into Bar-Specimen (Epstein Frame Tester) and Ring-Specimen (Toroidal Ring Tester). The characteristics of the electrical Silicon steel were measured using the instruments solely dedicated to measuring each specimen. The core loss of the Bar-Specimen, which is commonly used, was found to be less than that of the Ring-Specimen. This is a very important design factor in achieving the objectives of improving the product efficiency and predicting the performance of electrical equipment. It serves as a critical point of view in order to reduce the error between design value and product value. A comparative analysis was conducted regarding various characteristics (Hysteresis, B-H characteristic, Iron loss, Minor loop, Coercive force, Residual magnetic flux density, etc.) of the electrical silicon steel considered in the design of the electrical equipment according to the specimen.

• Journal of the Korean Magnetics Society
• /
• v.11 no.1
• /
• pp.1-7
• /
• 2001

We investigated to DC magnetic characteristics, the dependence of annealing temperature on the crystal grain and the crystalline orientation for grain-oriented silicon ribbon with 100 $\mu\textrm{m}$ final thickness manufactured by three times cold rolling method using the hot-rolled silicon steel plate as a raw material. The growth of (110)[001] Goss texture were almost observed in the whole area of the sample. The values of the saturation magnetic flux density B$\sub$s/ and the average ${\alpha}$ angle have 1.9 T and 4.6 degrees respectively. From this result we could be confirmed that the three times cold rolling method has a possibility of manufacture for oriented ultra-thin silicon ribbons much more simple and cheeper than the existing oriented silicon steel manufacturing method by means of more simplified producing process.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.56 no.6
• /
• pp.1039-1046
• /
• 2007

This paper presents the analysis for power consumption, mechanical vibration and acoustic noise characteristics of the Coreless and Slotless Brushless DC motor in Digital Lightening Processor(DLP) Motor with the Air-Dynamic Bearing. The Coreless BLDC motor has not the stator yoke as well as the stator slot to remove the unbalance force by the interaction between the stator yoke and Air-Dynamic Bearing clearance. The assembling tolerance and the processing error make the air-gap difference between the magnet and the stator yoke .which occurs the unbalanced electro-magnetic force in the Slotless BLDC motor. It imposes the air-dynamic bearing on the disturbance force and makes the Air-Dynamic Bearing vibrated and noised. Also, The attractive force between the magnet and the silicon steel stator yoke increases the power consumption. In this paper, the power consumption, mechanical vibration and acoustic noise of the Coreless BLDC motor and the Slotless BLDC motor with the silicon steel stator yoke are simulated, analyzed, and tested using the manufactured proto-type motors with Air-Dynamic bearing. The simulated and tested results present that the Coreless BLDC motor without the silicon steel stator yoke has the lower mechanical vibration and noise ,and lower power consumption than the Slotless BLDC motor with the silicon steel stator yoke in Digital Lightening Processor Motor with Air-Dynamic Bearing.

• Tribology and Lubricants
• /
• v.11 no.5
• /
• pp.78-86
• /
• 1995

The silicon nitride based ceramic cutting tool materials have been fabricated by gas pressure sintering (GPS) or hot pressing (HP). Their mechanical properties were measured and the effect of the fabrication variables on the properties were examined. Also, effect of adding TiN or TiC particulates on the mechanical properties of the silicon nitride ceramics were investigated. Ceramic cutting tools (ISO 120408) were made of the sintered bodies. Cutting performance test were performed on either conventional or NC lathe. The workpieces were grey cast iron, hardened alloy steel (AISI 4140, HRc>60) and Ni-based superalloy (Inconel 718). The results showed that fabrication variables, namely, sintering temperature and time, exerted a strong influence on the microstincture and mechanical properties of the sintered body, which, however, did not make much difference in wear resistance of the tools. High hardness of the tool containing TiC particulates exhibited good cutting performance. Extensive crater wear was observed on both monolithic and TiN-containing silicon nitride tools after cutting the hardened alloy steel. Inconel 718 was extremely difficult to cut by the current cutting tools.

• Journal of Korea Foundry Society
• /
• v.25 no.2
• /
• pp.95-101
• /
• 2005

This study has been carried out to investigate the microstructure of austempered high carbon cast steel with the variation of silicon and heat treatment conditions. The results show that an lower ausferritic structure is formed at the low austemepring temperature ($250{\sim}300^{\circ}C$) and an upper ausferritic structure is formed at the high austemepring temperature ($350{\sim}400^{\circ}C$). As an austempering temperature increased, the retained austenite volume fraction increased, however hardness decreased. Also, as a silicon content increased, the precipitation of cementite was suppressed, therefore 2nd reaction of autempering transformation was delayed.