A great deal of research is being carried out on forming a multilayer on the material instead of ... more A great deal of research is being carried out on forming a multilayer on the material instead of single layer. However, most studies of multilayer formation have been conducted using the plasma processing or spray coating method only for surface modification. Recently, a new nitriding process has been proposed to produce an aluminum nitride on the aluminum surface by using a barrel. In addition, this study proposes a new concept on the production of a multilayer, which has an AlN and Fe-Al intermetallic compound layer, between aluminum and stainless steel by using the barrel nitriding. By forming a multilayer at the interface between the different substrates, this process can be applied to as a bonding process. The barrel nitriding was carried out at 640 °C for 10hrs with Al2O3 powder and Al-Mg alloy powder. After barrel nitriding, the aluminum nitride (AlN) layer and Fe-Al intermetallic compound (Fe2Al5.4) layer were formed at the interface between pure aluminum and stainless steel. In addition, the thickness of the multilayer decreased with increasing the Ni concentration of stainless steel.
Journal of the Japan Society of Applied Electromagnetics and Mechanics, 2013
The extended Jiles-Atherton s model considered stress dependence is applied to silicon steel shee... more The extended Jiles-Atherton s model considered stress dependence is applied to silicon steel sheets and compared with the published hysteresis curves of silicon steel. Magnetic properties of silicon steel, which are important for the precise motor simulation, are affected by compressive stress. The extended Jiles-Atherton s model is found to well describe the published magnetization curves of silicon steel for small compressive stress, though it is difficult to express the magnetization property with large compressive stress. Since the silicon steel sheet has coating material on the surface and has different deformation ratio from the coating material, the different stress distribution generates within the silicon steel. It is considered to be a cause to make the different magnetic characteristics between the bulk steel and tie silicon steel sheets.
The motor core including a rotor core and a stator core, which is made from silicon steel sheets.... more The motor core including a rotor core and a stator core, which is made from silicon steel sheets. Iron loss increases during fixation of the stator core, e.g., by interlocking, welding, and shrink fitting installation. In this paper, the magnetic properties changes by each processing such as wire cutting, punching, interlocking and shrink fitting are investigated. Iron loss of the toroidal cores using punching, interlocking and shrink fitting are increased from 1.16 W/kg to 1.56 W/kg (34.4 % increased) at 50Hz, and from 21.1 W/kg to 27.5 W/kg (30.3 % increased) at 400 Hz compared with iron loss of wire cut toroidal core.
<jats:p>After the 9∙11 terrorism and America-Iraq war, apprehension of mass destruction wea... more <jats:p>After the 9∙11 terrorism and America-Iraq war, apprehension of mass destruction weapons such as bio-chemical agents calls for much more sensitive sensors which can detect toxic gases. In this study, semiconductor gas sensors based on tin oxide were examined to detect chemical agent simulants: dimethyl-methyl-phosponate (DMMP), di(propylene glycol) methyl ether (DPGME), acetonitrile, and dichloromethane. DMMP((CH3O)3), DPGME(C7H16O3), acetonitrile(CH3CN), and dichloromethane(CH2Cl2) gases are the simulants of nerve agent-sarin, vesicant agent-HN(N(CH2CH2Cl)3), blood agent-AC(HCN), and choking agent-CG(COCl2) gases, repectively. The SnO2 powder was prepared by a coprecipitation method from the mixture of tin chloride and zinc acetate dihydrate. Zinc oxide was doped into SnO2 from 1 wt% to 4 wt% to improve its reliability and sensitivity. To fabricate a thick film, powders were made into paste with organic binder of ethyl cellulose and screen-printed on the alumina substrate. The phase development and morphology of ZnO-doped SnO2 film were investigated by XRD (X-ray diffraction analysis), BET (surface and pore size analyzer), and SEM (scanning electron microscope). The gas sensing characteristics for target gases were examined with a flow-type measurement system. The concentrations of simulants were controlled from 500 ppb to 1500 ppb, and working temperatures were regulated from 250 to 400 .</jats:p>
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
Fe-Ni alloys can have a variety of magnetomechanical properties, depending on their composition. ... more Fe-Ni alloys can have a variety of magnetomechanical properties, depending on their composition. In order to study the magnetoelastic coupling of the alloys, we obtained the stress dependence of the longitudinal and transverse magnetostriction curves and three magnetoacoustic curves, i.e., the speeds of a longitudinal and two transverse waves propagating in a normal direction to the magnetic field. We obtained five curves, each for Ni, B-type Permalloy, and pure iron under tensile stresses from 0 to 40 MPa parallel to the magnetic field. It is known that the magnetoelastic coupling and the acoustoelasticity induce a uniaxial anisotropy in the elastic coefficients of the ferromagnetic materials. We propose a procedure to determine all the elastic coefficients from the above five curves. We also examine the variation of the elastic coefficients with magnetization by taking into account their stress dependence and comparing them with Fe-Ni alloys .
After the 9∙11 terrorism and America-Iraq war, apprehension of mass destruction weapons such as b... more After the 9∙11 terrorism and America-Iraq war, apprehension of mass destruction weapons such as bio-chemical agents calls for much more sensitive sensors which can detect toxic gases. In this study, semiconductor gas sensors based on tin oxide were examined to detect chemical agent simulants: dimethyl-methyl-phosponate (DMMP), di(propylene glycol) methyl ether (DPGME), acetonitrile, and dichloromethane. DMMP((CH3O)3), DPGME(C7H16O3), acetonitrile(CH3CN), and dichloromethane(CH2Cl2) gases are the simulants of nerve agent-sarin, vesicant agent-HN(N(CH2CH2Cl)3), blood agent-AC(HCN), and choking agent-CG(COCl2) gases, repectively. The SnO2 powder was prepared by a coprecipitation method from the mixture of tin chloride and zinc acetate dihydrate. Zinc oxide was doped into SnO2 from 1 wt% to 4 wt% to improve its reliability and sensitivity. To fabricate a thick film, powders were made into paste with organic binder of ethyl cellulose and screen-printed on the alumina substrate. The phase development and morphology of ZnO-doped SnO2 film were investigated by XRD (X-ray diffraction analysis), BET (surface and pore size analyzer), and SEM (scanning electron microscope). The gas sensing characteristics for target gases were examined with a flow-type measurement system. The concentrations of simulants were controlled from 500 ppb to 1500 ppb, and working temperatures were regulated from 250 to 400 .
To estimate the magnetic properties with two-dimensional AC-magnetization with two-dimensional DC... more To estimate the magnetic properties with two-dimensional AC-magnetization with two-dimensional DC-biased magnetization, three different grades of non-oriented electrical steel sheets with two-dimensional DC-biased magnetization were prepared. As a result, in the high grade specimen, the difference in the magnetic properties depending on the excitation direction (AC excitation direction is parallel to DC excitation direction) was larger than in the low grade specimen, and the magnetic properties were the best when the excitation direction was the rolling direction. Non-oriented electrical steel sheets have small magnetic anisotropy. High grade non-oriented electrical steel sheets have a large magnetic anisotropy to compare with low grade non-oriented electrical steel sheets. It is thought that magnetic anisotropy increased in the high grade non-oriented electrical steel sheets because the B-H loops under DC-biased magnetization were minor loops. In addition, the increase rate of the H widths and the increase rate of the iron losses depending on the excitation direction were relatively consistent. Since the iron loss is proportional to the area of the B-H loop, it is considered that the iron loss increased at the same rate as the H width of the B-H loop.
Iron-dust cores are produced from insulated iron particles by using the powder metallurgy pressur... more Iron-dust cores are produced from insulated iron particles by using the powder metallurgy pressure forming process. These dust cores are suitable for small motor cores because of their high shape flexibility; however, the iron loss of iron-dust cores is larger than conventional laminated cores. Generally, the insulation material between the iron particles degrades the magnetic property of the core. In this paper, the magnetic property of the iron-dust core in which the resin, which is usually used as insulation material, is replaced by the soft magnetic Mn-Zn ferrite or alumina is examined. We have found that the iron-dust core mixed with alumina particles shows higher space factor, 10% lower iron loss, and 30% higher permeability. Contrary to expectation, the magnetic properties of the iron-dust core deteriorate by mixing with soft magnetic Mn-Zn ferrite.
To estimate the magnetic properties of the magnetic material, magnetic flux density waveform (B w... more To estimate the magnetic properties of the magnetic material, magnetic flux density waveform (B waveform) must be sinusoidal wave. However, it is necessary to control the exciting waveform in consideration of the distortion, because voltage waveform induced by B-coil is distorted due to the magnetic properties. As a result, the IBCM can make B waveform sinusoidal wave with the least number of feedbacks than any control method. Because the IBCM performs noise cancelling for measured waveform and make accurate exciting waveform from measured waveform.
A great deal of research is being carried out on forming a multilayer on the material instead of ... more A great deal of research is being carried out on forming a multilayer on the material instead of single layer. However, most studies of multilayer formation have been conducted using the plasma processing or spray coating method only for surface modification. Recently, a new nitriding process has been proposed to produce an aluminum nitride on the aluminum surface by using a barrel. In addition, this study proposes a new concept on the production of a multilayer, which has an AlN and Fe-Al intermetallic compound layer, between aluminum and stainless steel by using the barrel nitriding. By forming a multilayer at the interface between the different substrates, this process can be applied to as a bonding process. The barrel nitriding was carried out at 640 °C for 10hrs with Al2O3 powder and Al-Mg alloy powder. After barrel nitriding, the aluminum nitride (AlN) layer and Fe-Al intermetallic compound (Fe2Al5.4) layer were formed at the interface between pure aluminum and stainless steel. In addition, the thickness of the multilayer decreased with increasing the Ni concentration of stainless steel.
Journal of the Japan Society of Applied Electromagnetics and Mechanics, 2013
The extended Jiles-Atherton s model considered stress dependence is applied to silicon steel shee... more The extended Jiles-Atherton s model considered stress dependence is applied to silicon steel sheets and compared with the published hysteresis curves of silicon steel. Magnetic properties of silicon steel, which are important for the precise motor simulation, are affected by compressive stress. The extended Jiles-Atherton s model is found to well describe the published magnetization curves of silicon steel for small compressive stress, though it is difficult to express the magnetization property with large compressive stress. Since the silicon steel sheet has coating material on the surface and has different deformation ratio from the coating material, the different stress distribution generates within the silicon steel. It is considered to be a cause to make the different magnetic characteristics between the bulk steel and tie silicon steel sheets.
The motor core including a rotor core and a stator core, which is made from silicon steel sheets.... more The motor core including a rotor core and a stator core, which is made from silicon steel sheets. Iron loss increases during fixation of the stator core, e.g., by interlocking, welding, and shrink fitting installation. In this paper, the magnetic properties changes by each processing such as wire cutting, punching, interlocking and shrink fitting are investigated. Iron loss of the toroidal cores using punching, interlocking and shrink fitting are increased from 1.16 W/kg to 1.56 W/kg (34.4 % increased) at 50Hz, and from 21.1 W/kg to 27.5 W/kg (30.3 % increased) at 400 Hz compared with iron loss of wire cut toroidal core.
<jats:p>After the 9∙11 terrorism and America-Iraq war, apprehension of mass destruction wea... more <jats:p>After the 9∙11 terrorism and America-Iraq war, apprehension of mass destruction weapons such as bio-chemical agents calls for much more sensitive sensors which can detect toxic gases. In this study, semiconductor gas sensors based on tin oxide were examined to detect chemical agent simulants: dimethyl-methyl-phosponate (DMMP), di(propylene glycol) methyl ether (DPGME), acetonitrile, and dichloromethane. DMMP((CH3O)3), DPGME(C7H16O3), acetonitrile(CH3CN), and dichloromethane(CH2Cl2) gases are the simulants of nerve agent-sarin, vesicant agent-HN(N(CH2CH2Cl)3), blood agent-AC(HCN), and choking agent-CG(COCl2) gases, repectively. The SnO2 powder was prepared by a coprecipitation method from the mixture of tin chloride and zinc acetate dihydrate. Zinc oxide was doped into SnO2 from 1 wt% to 4 wt% to improve its reliability and sensitivity. To fabricate a thick film, powders were made into paste with organic binder of ethyl cellulose and screen-printed on the alumina substrate. The phase development and morphology of ZnO-doped SnO2 film were investigated by XRD (X-ray diffraction analysis), BET (surface and pore size analyzer), and SEM (scanning electron microscope). The gas sensing characteristics for target gases were examined with a flow-type measurement system. The concentrations of simulants were controlled from 500 ppb to 1500 ppb, and working temperatures were regulated from 250 to 400 .</jats:p>
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
Fe-Ni alloys can have a variety of magnetomechanical properties, depending on their composition. ... more Fe-Ni alloys can have a variety of magnetomechanical properties, depending on their composition. In order to study the magnetoelastic coupling of the alloys, we obtained the stress dependence of the longitudinal and transverse magnetostriction curves and three magnetoacoustic curves, i.e., the speeds of a longitudinal and two transverse waves propagating in a normal direction to the magnetic field. We obtained five curves, each for Ni, B-type Permalloy, and pure iron under tensile stresses from 0 to 40 MPa parallel to the magnetic field. It is known that the magnetoelastic coupling and the acoustoelasticity induce a uniaxial anisotropy in the elastic coefficients of the ferromagnetic materials. We propose a procedure to determine all the elastic coefficients from the above five curves. We also examine the variation of the elastic coefficients with magnetization by taking into account their stress dependence and comparing them with Fe-Ni alloys .
After the 9∙11 terrorism and America-Iraq war, apprehension of mass destruction weapons such as b... more After the 9∙11 terrorism and America-Iraq war, apprehension of mass destruction weapons such as bio-chemical agents calls for much more sensitive sensors which can detect toxic gases. In this study, semiconductor gas sensors based on tin oxide were examined to detect chemical agent simulants: dimethyl-methyl-phosponate (DMMP), di(propylene glycol) methyl ether (DPGME), acetonitrile, and dichloromethane. DMMP((CH3O)3), DPGME(C7H16O3), acetonitrile(CH3CN), and dichloromethane(CH2Cl2) gases are the simulants of nerve agent-sarin, vesicant agent-HN(N(CH2CH2Cl)3), blood agent-AC(HCN), and choking agent-CG(COCl2) gases, repectively. The SnO2 powder was prepared by a coprecipitation method from the mixture of tin chloride and zinc acetate dihydrate. Zinc oxide was doped into SnO2 from 1 wt% to 4 wt% to improve its reliability and sensitivity. To fabricate a thick film, powders were made into paste with organic binder of ethyl cellulose and screen-printed on the alumina substrate. The phase development and morphology of ZnO-doped SnO2 film were investigated by XRD (X-ray diffraction analysis), BET (surface and pore size analyzer), and SEM (scanning electron microscope). The gas sensing characteristics for target gases were examined with a flow-type measurement system. The concentrations of simulants were controlled from 500 ppb to 1500 ppb, and working temperatures were regulated from 250 to 400 .
To estimate the magnetic properties with two-dimensional AC-magnetization with two-dimensional DC... more To estimate the magnetic properties with two-dimensional AC-magnetization with two-dimensional DC-biased magnetization, three different grades of non-oriented electrical steel sheets with two-dimensional DC-biased magnetization were prepared. As a result, in the high grade specimen, the difference in the magnetic properties depending on the excitation direction (AC excitation direction is parallel to DC excitation direction) was larger than in the low grade specimen, and the magnetic properties were the best when the excitation direction was the rolling direction. Non-oriented electrical steel sheets have small magnetic anisotropy. High grade non-oriented electrical steel sheets have a large magnetic anisotropy to compare with low grade non-oriented electrical steel sheets. It is thought that magnetic anisotropy increased in the high grade non-oriented electrical steel sheets because the B-H loops under DC-biased magnetization were minor loops. In addition, the increase rate of the H widths and the increase rate of the iron losses depending on the excitation direction were relatively consistent. Since the iron loss is proportional to the area of the B-H loop, it is considered that the iron loss increased at the same rate as the H width of the B-H loop.
Iron-dust cores are produced from insulated iron particles by using the powder metallurgy pressur... more Iron-dust cores are produced from insulated iron particles by using the powder metallurgy pressure forming process. These dust cores are suitable for small motor cores because of their high shape flexibility; however, the iron loss of iron-dust cores is larger than conventional laminated cores. Generally, the insulation material between the iron particles degrades the magnetic property of the core. In this paper, the magnetic property of the iron-dust core in which the resin, which is usually used as insulation material, is replaced by the soft magnetic Mn-Zn ferrite or alumina is examined. We have found that the iron-dust core mixed with alumina particles shows higher space factor, 10% lower iron loss, and 30% higher permeability. Contrary to expectation, the magnetic properties of the iron-dust core deteriorate by mixing with soft magnetic Mn-Zn ferrite.
To estimate the magnetic properties of the magnetic material, magnetic flux density waveform (B w... more To estimate the magnetic properties of the magnetic material, magnetic flux density waveform (B waveform) must be sinusoidal wave. However, it is necessary to control the exciting waveform in consideration of the distortion, because voltage waveform induced by B-coil is distorted due to the magnetic properties. As a result, the IBCM can make B waveform sinusoidal wave with the least number of feedbacks than any control method. Because the IBCM performs noise cancelling for measured waveform and make accurate exciting waveform from measured waveform.
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