摘要:

The tensor susceptibility of an antiferromagnetic with uniaxial anisotropy has been calculated using several modifications of the Bloch damping term. The axial component of the susceptibility is particularly simple and is readily tested by the Kronig‐Kramers dispersion relations as modified by Gourary. It is found that, of the damping terms considered, only one which includes relaxation to the instantaneous equilibrium magnetizations will pass this test.

ISSN:0021-8979    

DOI:10.1063/1.1723127

出版商:AIP    

年代:1958

数据来源: AIP

摘要:

After a brief report on the experiments which have been made on magnetic annealing, recent investigations on the magnetic anisotropy which is induced by cold rolling are described. The local and the average anisotropy induced by rolling was observed by means of domain pattern and torque measurement for (110)[001], (001)[110], (001)[100] rolling of single crystals and rolling of polycrystals. It was shown that the anisotropy for individual cases was well explained by assuming the ``slip‐induced directional order.'' Two types of the anisotropy i.e., long‐range order (fine slip) type and short range order (coarse slip) type, were calculated. Dependence on the degree of order and its difference between single and polycrystals are also discussed.

ISSN:0021-8979    

DOI:10.1063/1.1723128

出版商:AIP    

年代:1958

数据来源: AIP

摘要:

Iron alloys containing about 6.5 weight percent silicon are known to respond to heat treatment in a magnetic field. Since the degree of response has been observed to vary with sheet thickness, a study was made to better define this variation.Two different alloy compositions were cast in cylindrical molds. The ingots were drilled to form hollow cylinders which were sliced and polished to rings of final thicknesses of from 0.150‐in. to 0.0025‐in.dc hysteresis loops were measured on samples as annealed 2 hours at 1000°C in dry hydrogen, and as subsequently cooled at 40°C/hr from 900°C in a circumferential magnetic field of 10 oe.The differences in coercive force and maximum permeability between samples field annealed and not field annealed are thickness dependent, and are greater for thicker samples.The effects of thickness on coercive force are lessened by electropolishing, which greatly reduces the slope of theHcvs(1/d)‐curve for both the field‐annealed and not field‐annealed states. The maximum permeability is not found to be affected by electropolishing.

ISSN:0021-8979    

DOI:10.1063/1.1723129

出版商:AIP    

年代:1958

数据来源: AIP

摘要:

In a factorial experiment, a study has been made of the effects of small amounts of alloying elements and processing variables on the magnetic properties of the 50% nickel‐iron alloy. The composition variables were: three levels of manganese, two of silicon, two of sulfur, and two of oxygen. The processing variables were: hot rolling at two temperature levels, annealing or not annealing after hot rolling, and final annealing at six temperature levels. The ingots were processed to tape from which toroidal cores were made.The results of magnetic tests made with a constant current, flux‐reset core tester indicate that certain elements need to be added to the melt to produce a grain‐oriented alloy with satisfactory magnetic properties, and that the processing must be compatible with the additions made. The binary manganese‐oxygen addition was most beneficial. In general, hot rolling at a high temperature level was beneficial, and annealing after hot rolling was detrimental to the magnetic performance.

ISSN:0021-8979    

DOI:10.1063/1.1723131

出版商:AIP    

年代:1958

数据来源: AIP

摘要:

Quantitative pole density stereograms of {111}, {220}, {200}, and {113} poles of ⅛‐mil molybdenum permalloy tape were developed in order to establish its cold rolled deformation texture and annealed textures.Cold rolled the tape induced multiple slip common to all face‐centered‐cubic metals and developed (110) [3¯35] and (110) [33¯5] end orientations which deviate 5° about [110] from the recognized {110} ⟨112⟩ brass deformation texture.On annealing at 771°C the cold rolled tape was found to develop (120) [001]+(210) [001] and (113) [7¯8¯5] +(113) [785¯] orientations as components of the annealed texture which bear in general at 35°‐45° rotation orientation relationship about ⟨111⟩ with the cold rolled end orientations.Annealing at 1160°C developed the same texture as that obtained after 771°C annealing.From the pole figures made on 927°C annealed tape, the same annealed texture prevailed whether the pole figure was made on its full ⅛ mil thickness or on its central 0.00005 in. section.Hysteresis loop tracings made on the cold rolled tape revealed an apparent direction of easy magnetization along the rolling direction. No easy magnetization direction was revealed in the rolling plane on the annealed tapes. These findings support the deductions from the corresponding pole figures.

ISSN:0021-8979    

DOI:10.1063/1.1723132

出版商:AIP    

年代:1958

数据来源: AIP

摘要:

The (110) [001] texture in silicon iron arises by a process of secondary recrystallization after cold reduction of the strip in two stages separated by an anneal. It is possible to produce the same texture by a one‐stage or a three‐stage reduction process. The rolling textures and primary recrystallization textures for each of these processes have been experimentally determined and are all different. In spite of this, the (110) [001] secondary orientation develops in each case. It is tentatively suggested that impurities in the steel, already known to be important in controlling grain growth in silicon iron, also supply the directional forces leading to the (110) [001] texture.

ISSN:0021-8979    

DOI:10.1063/1.1723133

出版商:AIP    

年代:1958

数据来源: AIP

摘要:

The secondary recrystallization texture has been related to the structure developed during prior processing. The (110) [001] component of the primary recrystallization texture, from which secondary grains grow, develops from the (111) ⟨112⟩ doublet component in the prior recrystallization texture. If the material undergoes two rather than one prior recrystallization heat treatments (each separated by a cold reduction), the amount of the (110) [001] component in the primary recrystallization texture is in general increased, and as a consequence, the completeness of secondary recrystallization is promoted.

ISSN:0021-8979    

DOI:10.1063/1.1723134

出版商:AIP    

年代:1958

数据来源: AIP

摘要:

Cube textured magnetic sheet containing approximately 3% silicon in iron has been developed in the General Electric Company Research Laboratory. The magnitude of the cube texture as determined by torque magnetometer tests is of the order of 90% or greater when compared to a single crystal with a (100) [001] orientation. The magnitude of the texture was confirmed by x‐ray diffraction pole figures.Static dc magnetic tests and 60 cycle ac w loss tests made on single strip samples taken both parallel to the rolling direction and at right angles to the rolling direction indicate nearly equal magnetic properties in both directions of the sheet. These properties are equivalent to the magnetic properties measured in the single good direction of the ``grain oriented'' transformer material. Finally, two transformers were made: one using laminations of the cube textured silicon iron, the other of the ``grain oriented'' material. It was found that transformer made of the cube textured material produced significantly lower energy losses at all inductions and at 17 000 gauss the losses were approximately 60% of the losses produced by the ``grain oriented'' transformer. Similarly the current required to produce 17 000 gauss in the cube textured transformer was again about half that required to excite the ``grain oriented'' transformer to the same induction.

ISSN:0021-8979    

DOI:10.1063/1.1723135

出版商:AIP    

年代:1958

数据来源: AIP

摘要:

Cube oriented, (100) [001], iron silicon alloys have been prepared in thickness ranging from 0.8 mil to 11.0 mils. Both ac and dc magnetic properties are given for the alloys. The data show that comparable properties to commercial singly oriented steel of the (110) [001] texture are obtained both parallel and perpendicular to the rolling direction. The magnetic properties are sensitive to both the amount of cube oriented grains and the distribution of the directions about the rolling direction of the sheet.

ISSN:0021-8979    

DOI:10.1063/1.1723136

出版商:AIP    

年代:1958

数据来源: AIP

摘要:

Low values of residual induction have been observed for different heat treatments in 0.007 and 0.014 in. thick sheets of aluminum‐iron alloys containing 10 to 16 weight percent aluminum. For these materials the ratio of residual induction (Br) to induction at 100 oersteds (B100) gave values of 0.05 to 0.1. These low residual induction values apparently occur at compositions having zero crystal anisotropy for both furnace‐cooled and water‐quenched alloys. Domain patterns were observed in these lowBralloys but, in general, no evidence of domain patterns was observed in the same alloys when theBr/B100ratio was increased, through suitable heat treatment, to a value greater than about 0.2. The fairly high magnetostriction of the alloys around the Fe3Al composition and the stress produced by cooling through differently ordered regions may be considered to produce a high ``stress anisotropy'' resulting in pronounced domain patterns and perhaps also to contribute to the lowering of the residual induction of these alloys.

ISSN:0021-8979    

DOI:10.1063/1.1723137

出版商:AIP    

年代:1958

数据来源: AIP