This Technical Report describes the general principle and technical details of the methods of measurement of the DC magnetic properties of permanent magnet materials in an open magnetic circuit using a superconducting magnet (SCM).<\/p>\n
This method is applicable to permanent magnet materials, such as those specified in IEC 60404-8-1, the properties of which are presumed homogeneous throughout their volume.<\/p>\n
There are two methods:<\/p>\n
the SCM-Vibrating Sample Magnetometer (VSM) method;<\/p>\n<\/li>\n
the SCM-Extraction method.<\/p>\n<\/li>\n<\/ul>\n
This document also describes methods to correct the influence of the self-demagnetizing field in the test specimen on the demagnetization curve measured in an open magnetic circuit. The magnetic properties are determined from the corrected demagnetization curve.<\/p>\n
\nNOTE These SCM-methods can determine the magnetic properties of permanent magnet materials with coercivity higher than 2 MA\/m. The methods of measurement in a closed magnetic circuit specified in IEC 60404-5 can lead to significant measurement error due to saturation effects in the pole pieces of yoke for the magnetic materials with coercivity higher than 1,6 MA\/m (see IEC 60404-5).<\/p>\n<\/blockquote>\n
PDF Catalog<\/h4>\n
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\n PDF Pages<\/th>\n PDF Title<\/th>\n<\/tr>\n \n 2<\/td>\n undefined <\/td>\n<\/tr>\n \n 4<\/td>\n CONTENTS <\/td>\n<\/tr>\n \n 7<\/td>\n FOREWORD <\/td>\n<\/tr>\n \n 9<\/td>\n INTRODUCTION <\/td>\n<\/tr>\n \n 11<\/td>\n 1 Scope
2 Normative references
3 Terms and definitions <\/td>\n<\/tr>\n\n 12<\/td>\n Figures
Figure 1 \u2013 Demagnetization curve J(H) <\/td>\n<\/tr>\n\n 13<\/td>\n 4 General principle
4.1 Principle of the method
Figure 2 \u2013 Schematic diagrams of the test apparatus <\/td>\n<\/tr>\n\n 14<\/td>\n 4.2 Superconducting magnet (SCM) <\/td>\n<\/tr>\n \n 15<\/td>\n 4.3 Magnetic field strength sensor (H sensor)
4.4 Magnetic dipole moment detection coil (M coil)
Figure 3 \u2013 Schematic diagrams of the first order gradiometer coil <\/td>\n<\/tr>\n\n 16<\/td>\n 4.5 Specimen rod and moving device
4.6 Measuring devices and the data processing device
5 Test specimen <\/td>\n<\/tr>\n\n 17<\/td>\n 6 Preparation of measurement
6.1 Measurement of volume of the test specimen
6.2 Initial magnetization of the test specimen to saturation
7 Determination of magnetic polarization
7.1 Measurement of the magnetic dipole moment <\/td>\n<\/tr>\n\n 18<\/td>\n 7.2 Determination of magnetic polarization <\/td>\n<\/tr>\n \n 19<\/td>\n 8 Measurement of magnetic field
9 Calibration of the magnetic dipole moment detection coil (M coil)
10 Determination of demagnetization curve <\/td>\n<\/tr>\n\n 20<\/td>\n 11 Demagnetizing field correction
11.1 General
Figure 4 \u2013 Relationship between magnetic polarization and self-demagnetizing field <\/td>\n<\/tr>\n\n 21<\/td>\n Figure 5 \u2013 Schematic diagram of the demagnetizing field correction <\/td>\n<\/tr>\n \n 22<\/td>\n 11.2 Method A: Method using a demagnetizing factor determined by the shape of the test specimen only
11.3 Method B: Method using a demagnetizing factor determined by the shape and the magnetic susceptibility of the test specimen
Tables
Table 1 \u2013 Features of the demagnetizing field correction methodsin comparison with Method B <\/td>\n<\/tr>\n\n 23<\/td>\n 11.4 Method C: Method using an inverse analysis considering the spatial distribution of the self-demagnetizing field strength in the test specimen
12 Determination of principal magnetic properties
12.1 Remanent magnetic polarization Jr
Figure 6 \u2013 Conceptual diagram of the procedure of Method C <\/td>\n<\/tr>\n\n 24<\/td>\n 12.2 Maximum energy product (BH)max
12.3 Coercivity (HcJ and HcB)
13 Reproducibility
14 Test report
Table 2 \u2013 Reproducibility of the magnetic properties <\/td>\n<\/tr>\n\n 26<\/td>\n Annex A (informative)SCM-Magnetometer method
Figure A.1 \u2013 Schematic diagram of the test apparatusfor the SCM-Magnetometer method <\/td>\n<\/tr>\n\n 27<\/td>\n Figure A.2 \u2013 Schematic diagrams of the test apparatus for the methodin a closed magnetic circuit in accordance with IEC 60404-5 <\/td>\n<\/tr>\n \n 28<\/td>\n Annex B (informative)Effects of the test specimen dimensions
Figure B.1 \u2013 Effects of test specimen dimensions on magnetic properties [Br, HcJ, HcB and (BH)max] for Nd-Fe-B sintered magnets with different coercivities <\/td>\n<\/tr>\n\n 29<\/td>\n Annex C (informative)Superconducting magnets (SCMs)
Table C.1 \u2013 Performance of SCMs <\/td>\n<\/tr>\n\n 30<\/td>\n Figure C.1 \u2013 Typical cross-sectional structure of the ceramic SCM <\/td>\n<\/tr>\n \n 31<\/td>\n Annex D (informative)Magnetic dipole moment detection coils (M coils)
Figure D.1 \u2013 Schematic diagram of the second order gradiometercoil for the SCM-VSM method <\/td>\n<\/tr>\n\n 32<\/td>\n Figure D.2 \u2013 Schematic diagram of the dependence of induced voltageon the position of the test specimen in the SCM-Extraction method <\/td>\n<\/tr>\n \n 33<\/td>\n Annex E (informative\/normative)Details of the demagnetizing field correction
E.1 General
E.2 Symbols <\/td>\n<\/tr>\n\n 34<\/td>\n E.3 Method using a demagnetizing factor determined by the shape and magnetic susceptibility of the test specimen (Method B)
Figure E.1 \u2013 Axes of a cuboid magnet <\/td>\n<\/tr>\n\n 36<\/td>\n E.4 Method using an inverse analysis considering the spatial distribution of the self-demagnetizing field strength in the test specimen (Method C) <\/td>\n<\/tr>\n \n 37<\/td>\n Figure E.2 \u2013 Conceptual diagram of the procedure of Method C <\/td>\n<\/tr>\n \n 38<\/td>\n Figure E.3 \u2013 Flowchart of the procedure of Method C <\/td>\n<\/tr>\n \n 40<\/td>\n Figure E.4 \u2013 Comparison of the demagnetization curves correctedusing demagnetizing field correction Methods A, B and C <\/td>\n<\/tr>\n \n 41<\/td>\n Annex F (informative)Result of the international round robin test of magnetic properties of permanent magnets using the SCM-VSM and SCM-Extraction methods
F.1 General
F.2 Protocol of the RRT
Table F.1 \u2013 Nominal values of coercivity <\/td>\n<\/tr>\n\n 42<\/td>\n F.3 Result of the RRT
Figure F.1 \u2013 Comparison of Jr measured by the laboratories
Table F.2 \u2013 Participating laboratories and their employed measuring methods <\/td>\n<\/tr>\n\n 43<\/td>\n Figure F.2 \u2013 Comparison of HcJ measured by the laboratories
Figure F.3 \u2013 Comparison of (BH)max measured by the laboratories <\/td>\n<\/tr>\n\n 44<\/td>\n Table F.3 \u2013 Comparison of magnetic properties measured by the laboratories <\/td>\n<\/tr>\n \n 45<\/td>\n F.4 Reproducibility of the measurements
Figure F.4 \u2013 Comparison of hysteresis loops measured by the laboratories <\/td>\n<\/tr>\n\n 46<\/td>\n Figure F.5 \u2013 Relative standard deviation of Jr, HcJ and (BH)max
Table F.4 \u2013 Comparison of the reproducibility <\/td>\n<\/tr>\n\n 47<\/td>\n Bibliography <\/td>\n<\/tr>\n<\/table>\n","protected":false},"excerpt":{"rendered":" Permanent magnet (magnetically hard) materials. Methods of measurement of magnetic properties in an open magnetic circuit using a superconducting magnet<\/b><\/p>\n
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\n Published By<\/td>\n Publication Date<\/td>\n Number of Pages<\/td>\n<\/tr>\n \n BSI<\/b><\/a><\/td>\n 2021<\/td>\n 50<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n","protected":false},"featured_media":376376,"template":"","meta":{"rank_math_lock_modified_date":false,"ep_exclude_from_search":false},"product_cat":[285,2641],"product_tag":[],"class_list":{"0":"post-376366","1":"product","2":"type-product","3":"status-publish","4":"has-post-thumbnail","6":"product_cat-17-220-20","7":"product_cat-bsi","9":"first","10":"instock","11":"sold-individually","12":"shipping-taxable","13":"purchasable","14":"product-type-simple"},"_links":{"self":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product\/376366","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product"}],"about":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/types\/product"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/media\/376376"}],"wp:attachment":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/media?parent=376366"}],"wp:term":[{"taxonomy":"product_cat","embeddable":true,"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product_cat?post=376366"},{"taxonomy":"product_tag","embeddable":true,"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product_tag?post=376366"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}