定价： 646元 加购物车

3.1 Permeameters require the use of yokes to complete the magnetic circuit and are therefore inherently less accurate than ring test methods. Refer to Test Method A596/A596M for further details on ring test methods. However, when testing certain shapes as bars or when magnetic field strength in excess of 200 Oe [16 kA/m] is required, permeameters are the only practical means of measuring magnetic properties. 3.2 This test method is suitable for specification acceptance, service evaluation, research and development and design. 3.3 When the test specimen is fabricated from a larger sample and is in the same condition as the larger sample, it may not exhibit magnetic properties representative of the original sample. In such instances the test results, when viewed in context of past performance history, will be useful for judging the suitability of the material for the intended application. 1.1 This test method provides dc permeameter tests for the basic magnetic properties of soft magnetic materials in the form of bars, rods, wire, or strip specimens which may be cut, machined, or ground from cast, compacted, sintered, forged, extruded, rolled, or other fabricated materials. It includes tests for determination of the normal induction under symmetrically cyclically magnetized (SCM) conditions and the hysteresis loop (B-H loop) taken under conditions of rapidly changing or steep wavefront reversals of the direct current magnetic field strength. This method has been historically referred to as the ballistic test method. For testing hard or permanent magnet materials, Test Method A977/A977M shall be used. 1.2 This test method shall be used in conjunction with Practice A34/A34M. 1.3 This test method covers a range of magnetic field strength in the specimen from about 0.05 Oe [4 A/m] up to above 5000 Oe [400 kA/m] through the use of several permeameters. The separate permeameters cover this test region in several overlapping ranges. 1.4 Normal induction and hysteresis properties may be determined over the magnetic flux density range from essentially zero to the saturation induction for most materials. 1.5 Recommendations of the useful magnetic field strength range for each of the permeameters are shown in Table 1.2 Permeameters particularly well suited for general testing of soft magnetic materials are shown in boldface. Also, see Sections 3 and 4 for general limitations relative to the use of permeameters. 1.6 The symbols and abbreviated definitions used in this test method appear with Fig. 1 and in appropriate sections of this document. For the official definitions, see Terminology A340. Note that the term magnetic flux density used in this document is synonymous with the term magnetic induction. FIG. 1 Basic Circuit Using Permeameter Note 1:  A1—Multirange ammeter (main current) A2—Multirange ammeter (hysteresis current) B—Magnetic flux density test position for Switch S3 F—Electronic Fluxmeter H—Magnetic field strength test position for Switch S3 N1—Magnetizing coil N2—Magnetic flux sensing (B) coil N3—Magnetic field strength (H) sensing coil R1—Main current control rheostat R2—Hysteresis current control rheostat S1—Reversing switch for magnetizing current S2—Shunting switch for hysteresis current control rheostat S3—Fluxmeter selector switch SP—Specimen 1.7 Warning—Mercury has been designated by EPA and many state agencies as a hazardous material that can cause central nervous system, kidney, and liver damage. Mercury, or its vapor, may be hazardous to health and corrosive to materials. Caution should be taken when handling mercury and mercury-containing products. See the applicable product Material Safety Data Sheet (MSDS) for details and EPA’s website (http://www.epa.gov/mercury/faq.htm ) for additional information. Users should be aware that selling mercury or mercury-containing products, or both, in your state may be prohibited by state law. 1.8 The values and equations stated in customary (cgs-emu and inch-pound) or SI units are to be regarded separately as standard. Within this standard, SI units are shown in brackets except for the sections concerning calculations where there are separate sections for the respective unit systems. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in nonconformance with this standard. 1.9 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.10 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

定价： 646元 加购物车

定价： 712元 加购物车

定价： 590元 加购物车

定价： 646元 加购物车

This specification covers commonly used wrought nickel-iron soft magnetic alloys produced or supplied expressly for use in magnetic cores and other parts requiring high magnetic permeability, high electrical resistivity, low coercive field strength, and low core loss. This specification does not cover material produced by casting or by powder metallurgy techniques. These materials are capable of being produced in a wide variety of forms and conditions such as forging billet, hot-rolled plate, strip, and bar, cold-finished bars, cold-rolled sheep and strip, shaped bar and wire. Four specific alloy types containing nominally 45, 48, 76 and 80 nickel with various other elements are covered by this specification. The alloy chemistry requirements are listed. Magnetic property requirements for the different alloys, product forms and sizes are specified. Typical physical property data and useful heat treatment information are provided in appendices.1.1 This specification covers commonly used wrought nickel-iron soft magnetic alloys produced or supplied expressly for use in magnetic cores and other parts requiring high magnetic permeability, high electrical resistivity, low coercive field strength, and low core loss.1.2 This specification covers materials supplied by a producer or converter to the form and physical condition desired for fabrication into parts that will later be given a final heat treatment to achieve the desired magnetic characteristics. It covers materials supplied in the form of forging billet; hot-rolled plate, strip, and bar; cold-finished bar; cold-rolled and annealed sheet and strip; shaped bar and wire; and wire.1.2.1 This specification does not cover either powder metallurgically produced or cast parts.1.2.2 This specification lists requirements for strip products having isotropic or semi-isotropic magnetic properties but does not include requirements for anisotropic or square hysteresis loop alloys or alloys processed to yield flattened hysteresis loops by use of heat treatments in an applied magnetic field.1.2.3 This specification does not cover alloys modified by the addition of elements such as sulfur and selenium to enhance machinability.1.3 The values stated in SI units are to be regarded as standard. The values given in parentheses are mathematical conversions to customary (cgs-emu and inch-pound) units which are provided for information only and are not considered standard.1.3.1 There are selected values presented in two units, both of which are in acceptable SI units. These are differentiated by the word “, or,” as in “g/cm3, or, (kg/m3).” In addition, values for mean linear coefficient of expansion in Table X1.1 are shown solely in μm/m/°C in keeping with prior versions of this standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

定价： 590元 加购物车

定价： 646元 加购物车

4.1 This test method is designed for testing of either toroidal or mated soft magnetic core components over a range of temperatures, frequencies, and flux densities.4.2 The reproducibility and repeatability of this test method are such that it is suitable for design, specification acceptance, service evaluation, and research and development.1.1 This test method covers the equipment, procedures, and measurement of core loss of either toroidal or mated soft magnetic core components, such as soft ferrite cores, iron powder cores, and so forth, over ranges of controlled ambient temperatures typically from −20 to +120°C, frequencies from 10 kHz to 1 MHz, under sinusoidal flux conditions.1.2 The values and equations stated in customary (cgs-emu and inch-pound) or SI units are to be regarded separately as standard. Within this test method, SI units are shown in brackets except for the sections concerning calculations where there are separate sections for the respective unit systems. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in nonconformance with this standard.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

定价： 590元 加购物车

定价： 515元 加购物车

5.1 Values of density are used for converting volumes to units of mass and for correcting measured volumes at the measured temperature to a standard temperature using Practice D4311/D4311M.NOTE 2: The quality of the results produced by this standard are dependent on the competence of the personnel performing the procedure and the capability, calibration, and maintenance of the equipment used. Agencies that meet the criteria of Specification D3666 are generally considered capable of competent and objective testing, sampling, inspection, etc. Users of this standard are cautioned that compliance with Specification D3666 alone does not completely ensure reliable results. Reliable results depend on many factors; following the suggestions of Specification D3666 or some similar acceptable guideline provides a means of evaluating and controlling some of those factors.1.1 This test method covers the determination of the relative density and density of semi-solid asphalt materials, asphalt binders, asphalt cements, and soft-tar pitches by use of a digital density meter (U-tube).NOTE 1: Alternate methods for determining the density of semi-solid and solid asphalt materials and asphalt binders include Test Methods D3289, D3142/D3142M, and D70/D70M.1.2 The values stated in SI units are to be regarded as standard. The values given in parentheses are for information only. No other units of measurement are included in this standard, with the exception of temperature measurements. Units provided in degrees Fahrenheit are for reference purposes only. Temperatures given in degrees Celsius are to be considered standard.1.3 This test method should not be applied to petroleum distillates other than asphalt and asphalt binders. For the determination of density of all other petroleum distillates and viscous oils, use Test Method D4052 or D5002, or ISO 12185.1.4 The text of this standard references notes and footnotes which provide explanatory material. These footnotes (excluding those in tables and figures) shall not be considered as requirements of the standard.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

定价： 515元 加购物车

定价： 156元 / 折扣价： 133 元 加购物车

本文件适用于需解决快速、稳定接入WLAN网络的智能家电/家居设备。

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定价： 598元