JPS60247155A - Method and apparatus for measuring particle size of crystal - Google Patents
Method and apparatus for measuring particle size of crystalInfo
- Publication number
- JPS60247155A JPS60247155A JP10404684A JP10404684A JPS60247155A JP S60247155 A JPS60247155 A JP S60247155A JP 10404684 A JP10404684 A JP 10404684A JP 10404684 A JP10404684 A JP 10404684A JP S60247155 A JPS60247155 A JP S60247155A
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- coil
- magnetization
- magnetic
- grain size
- flux density
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
- G01N27/72—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating magnetic variables
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
- G01N27/72—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating magnetic variables
- G01N27/725—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating magnetic variables by using magneto-acoustical effects or the Barkhausen effect
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- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Investigating Or Analyzing Materials By The Use Of Magnetic Means (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明はバルクハウゼン雑音に基づいて磁性体の結晶粒
度を測定する方法及びその実施に使用する装置、特にオ
ンラインで測定可能な結晶粒度測定装置に関する。[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for measuring the crystal grain size of a magnetic material based on Barkhausen noise, and an apparatus used to carry out the method, particularly a crystal grain size measuring apparatus that can be measured online. Regarding.
鋼板の安定供給２品質確認のために鋼板を全域にわたり
検査する必要性が高まっており、これには非破壊検査が
採用されている。Stable supply of steel plates 2 In order to confirm quality, there is an increasing need to inspect steel plates over the entire area, and non-destructive testing is being adopted for this purpose.
鋼板の品質のうち成形性、加工性等は結晶粒度と関係が
あり、結晶粒度はその評価をする上で重要な指標となる
。Among the qualities of steel sheets, formability, workability, etc. are related to grain size, and grain size is an important index for evaluation.
この結晶粒度を非破壊的に測定する方法とじては、例え
ばＴｈｅ Ｕｓｅ ｏｆ Ｂａｒｋｈａｕｓｅｎ Ｎｏ
１ｓｅ Ａｎａｌｙｓｉｓｉｎ Ｎｏｎｄｅｓｔｒｕｃ
ｔｉｖｅ Ｔｅｓｔｉｎｇ （Ｓｕｂｍｉｔｔｅｄ ｆ
ｏｒｐｕｂｌｉｃａｔｉｏｎ ｉｎ Ｊｕｎｅ １９７
８． ）による方法がある。A method for non-destructively measuring this grain size is, for example, as described in The Use of Barkhausen No.
1se Analysis
tive Testing (Submitted
publication in June 197
8. ) is the method.
この方法は、例えば鋼板を０．２ Ｈｚ程度以下の低い
周波数にて磁気飽和するまで励磁し、そのとき発生する
バルクハウゼン雑音を検出出来るように鋼板表面での磁
力線の方向が鋼板表面と平行となるように磁化し、検出
コイルにて所定期間検出し、検出されたバルクハウゼン
雑音の数に基づいて結晶粒度を測定する方法である。In this method, for example, a steel plate is excited at a low frequency of about 0.2 Hz or less until it reaches magnetic saturation, and the direction of the magnetic field lines on the steel plate surface is parallel to the steel plate surface so that the Barkhausen noise generated at that time can be detected. In this method, the grain size is measured based on the number of detected Barkhausen noises, which is magnetized so as to be detected by a detection coil for a predetermined period of time.
このようにバルクハウゼン雑音を検出するのは、この雑
音が強磁性体の磁化過程において生ずる磁壁の不連続移
動に伴って発生するものであり、磁壁の不連続移動が結
晶粒界で生ずるため磁化の単位周期当たりの雑音数が結
晶粒度と相関をもっためである。Barkhausen noise is detected in this way because this noise is generated due to the discontinuous movement of the domain wall that occurs during the magnetization process of a ferromagnetic material, and because the discontinuous movement of the domain wall occurs at the grain boundaries, the magnetization This is because the number of noises per unit period of is correlated with the crystal grain size.
而してこの方法は製造工程内にてオンライン測定するの
に不適である。即ち、測定に使用する交流が０．２）１
重程度以下の低い周波数であり、バルクハウゼン雑音の
計数には少なくともその半周期を必要とするため測定に
２．５秒を要する。これに対して、例えば製造工程での
鋼板の移送速度は２００ｍ／分程度であり、このため２
．５秒間の測定では８．３ｍの長い測定区間の平均値と
なる。従ってこのような測定値では鋼板に部分的な材質
異常があってもこれを確認できずに見落とすことになる
という欠点があり、このため適用が見送られていた。Therefore, this method is not suitable for on-line measurement within the manufacturing process. That is, the AC used for measurement is 0.2)1
It is a low frequency below the critical level, and counting Barkhausen noise requires at least a half period of the noise, so measurement requires 2.5 seconds. On the other hand, for example, the transport speed of steel plates in the manufacturing process is about 200 m/min, so 2
．． The measurement for 5 seconds is the average value over a long measurement section of 8.3 m. Therefore, such measurement values have the disadvantage that even if there is a local material abnormality in the steel plate, it cannot be confirmed and is overlooked, and for this reason, its application has been postponed.
本発明は斯かる欠点を解消すべくなされたものであり、
その目的とするところは測定時間を短縮することにより
、移動する測定対象物をより短い区間にて、また各部の
結晶粒度を測定できるバルクハウゼン雑音による結晶粒
度測定方法及びその実施に使用する装置を提供するにあ
る。The present invention has been made to eliminate such drawbacks,
The purpose is to shorten the measurement time and develop a grain size measurement method using Barkhausen noise that can measure the grain size of each part of a moving object over a shorter distance. It is on offer.
本発明に係る結晶粒度測定方法は、磁性体の結晶粒度を
バルクハウゼン雑音に基づいて測定する方法において、
前記磁性体を磁気飽和したのち磁束密度を残留磁束密度
又はこれに近いレベルに低減し、この状態にて磁気飽和
させない範囲で交流磁化し、このとき発生するバルクハ
ウゼン雑音の数を計数し、その計数値より磁性体の結晶
粒度を測定することを特徴とする。The crystal grain size measuring method according to the present invention is a method for measuring the crystal grain size of a magnetic material based on Barkhausen noise.
After the magnetic material is magnetically saturated, the magnetic flux density is reduced to the residual magnetic flux density or a level close to it, and in this state, AC magnetization is performed within a range that does not cause magnetic saturation, and the number of Barkhausen noises generated at this time is counted. It is characterized by measuring the crystal grain size of the magnetic material from the counted value.
以下本発明を図面に基づき具体的に説明する。 The present invention will be specifically explained below based on the drawings.
第１図は本発明方法を実施するに好適な装置の模式図で
あり、図中Ｐは鋼管製造ライン上を白抜矢符方向へ移送
されている鋼管を示す。鋼管Ｐの上流側には鋼管Ｐが挿
通するように磁気飽和用コイル１が固設されており、コ
イル１には直流電源２から所定の直流が通電されている
。FIG. 1 is a schematic diagram of an apparatus suitable for carrying out the method of the present invention, and in the figure, P indicates a steel pipe being transported in the direction of an open arrow on a steel pipe manufacturing line. A magnetic saturation coil 1 is fixedly installed on the upstream side of the steel pipe P so that the steel pipe P is inserted therethrough, and a predetermined direct current is supplied to the coil 1 from a direct current power supply 2 .
コイル１の下流側にはコイル１の磁場が及ばない位置に
、同心状に２重に組合された内側の検出コイル３と外側
の交流磁化用コイル４が、検出コイル３に鋼管Ｐが挿通
するように設けられており、交流磁化用コイル４には発
振器６にて発生せしめられた所定の周波数の交流が増幅
器５にて増幅されて通電されている。On the downstream side of the coil 1, in a position where the magnetic field of the coil 1 does not reach, an inner detection coil 3 and an outer AC magnetization coil 4 are concentrically combined in double layers, and a steel pipe P is inserted through the detection coil 3. The alternating current magnetizing coil 4 is energized with alternating current of a predetermined frequency generated by an oscillator 6 and amplified by an amplifier 5.
鋼管Ｐは磁気飽和用コイル１にて磁気飽和され、その部
分が通り抜けるとコイル１からの磁場の強さに応じて減
磁していき、コイル４の上流側にて残留磁束密度レベル
となり、そのレベルのままコイル４へ導かれる。The steel pipe P is magnetically saturated by the magnetic saturation coil 1, and when that part passes through, it demagnetizes according to the strength of the magnetic field from the coil 1, and reaches the residual magnetic flux density level on the upstream side of the coil 4, and its It is guided to coil 4 with the same level.
そしてこの残留磁束密度レベル部分がコイル４の磁場内
へ入ると、その部分は交流磁化用コイル４にて交流磁化
される。コイル４による磁化は磁気飽和させないレベル
となるように増幅器５の利得を設定しておく。When this residual magnetic flux density level portion enters the magnetic field of the coil 4, that portion is AC magnetized by the AC magnetization coil 4. The gain of the amplifier 5 is set so that the magnetization by the coil 4 is at a level that does not cause magnetic saturation.
検出コイル３は鋼管Ｐからのバルクハウゼン雑音を検出
し、検出されたパルス信号は増幅器７へ送られて増幅さ
れ、次いでフィルタ８にてバルクハウゼン雑音以外の雑
音成分が゛除去されて計数器９へ出力される。The detection coil 3 detects Barkhausen noise from the steel pipe P, and the detected pulse signal is sent to the amplifier 7 and amplified. Then, the filter 8 removes noise components other than the Barkhausen noise, and the pulse signal is sent to the counter 9. Output to.
計数器９はフィルタ８からのパルス信号を予め設定され
た測定に必要な期間、例えば磁化半周期。A counter 9 measures the pulse signal from the filter 8 for a predetermined period of time required for measurement, for example a half cycle of magnetization.
１周期にて計数し、計数値を記録計１０にて記録する。It is counted in one cycle and the counted value is recorded by the recorder 10.
このように構成された装置による鋼管Ｐの磁化履歴は次
のようになる。移送される鋼管Ｐはまず磁気飽和用コイ
ル１にて第２図の実線にて示すように点０の未磁化状態
から磁気飽和する（Ｈｓ）まで直流磁化され、その個所
がコイル１を抜は出ると磁場の強さくＨ）が減少して磁
束密度（Ｂ）は所定のヒステリシス曲線に従って減少し
、コイル１による磁場の強さがゼロになっても磁束密度
はゼロに戻らず所定の磁束密度、つまり残留磁束密度（
Ｂｒ）レベルを維持する。このような磁気飽和。The magnetization history of the steel pipe P by the device configured as described above is as follows. The steel pipe P to be transferred is first magnetized with direct current in the magnetic saturation coil 1 from the unmagnetized state at point 0 to magnetic saturation (Hs) as shown by the solid line in FIG. When it comes out, the strength of the magnetic field (H) decreases and the magnetic flux density (B) decreases according to a predetermined hysteresis curve, and even when the strength of the magnetic field from coil 1 becomes zero, the magnetic flux density does not return to zero and remains at the predetermined magnetic flux density. , that is, the residual magnetic flux density (
Br) maintain the level. Such magnetic saturation.
減磁又は消磁の原理により鋼管Ｐがコイル１に導かれる
前に磁化されていたとしてもその磁化状態に影響されず
一定の磁束密度となった状態でコイル３及びコイル４内
へ導入される。Due to the principle of demagnetization or demagnetization, even if the steel pipe P is magnetized before being guided into the coil 1, it is not affected by the magnetization state and is introduced into the coils 3 and 4 with a constant magnetic flux density.
そしてこの鋼管Ｐの残留磁束密度レベル部分は交流磁化
用コイル４内へ移送されてコイル４内付近にて磁気飽和
しないように交流磁化される。このときの磁場の強さと
磁束密度とは第２図に示すようにループ状にて描かれる
関係となる。また磁場の強さと磁束密度との変化は、第
３図に第２図の一部Ａを拡大して示すように階段的に変
化し、このとき結晶内では磁壁の不連続移動が生し、こ
のため検出コイル３はこれをバルクハウゼン雑音と称さ
れるパルス信号として検出する。The residual magnetic flux density level portion of the steel pipe P is transferred into the AC magnetization coil 4 and is AC magnetized so as not to be magnetically saturated near the inside of the coil 4. The strength of the magnetic field and the magnetic flux density at this time have a relationship drawn in a loop shape as shown in FIG. In addition, changes in the magnetic field strength and magnetic flux density change stepwise, as shown in Figure 3, which is an enlarged view of part A in Figure 2, and at this time, discontinuous movement of domain walls occurs within the crystal. Therefore, the detection coil 3 detects this as a pulse signal called Barkhausen noise.
検出信号は増幅器７にて増幅され、次いでフィルタ８に
てバルクハウゼン雑音以外の雑音成分が除去されて計数
器９にて１測定期間毎に計数される。The detection signal is amplified by an amplifier 7, noise components other than Barkhausen noise are removed by a filter 8, and counted by a counter 9 every measurement period.
計数されたパルス個数と結晶粒度との間には次の関係が
ある。The following relationship exists between the counted number of pulses and the grain size.
第４図は横軸に粒度番号（Ｎ）をとり、縦軸にパルス個
数（ＸＩＯ−２）をとって両者の関係を示したグラフで
あり、破線はバラツキ幅、実線はその中心値を示す。こ
の図より理解される如く本発明によるパルス計数値はＪ
ＩＳ Ｇ ０５５２号に規定された鋼のフェライト結晶
粒度試験方法により測定した粒度番号（Ｎ）に対して±
０．６の誤差内にあり、精度よく結晶粒度を測定し得る
。そしてこの測定を鋼管Ｐ全長にわたり行うことにより
全長の結晶粒度分布がわかる。Figure 4 is a graph showing the relationship between the particle size number (N) on the horizontal axis and the number of pulses (XIO-2) on the vertical axis, where the broken line shows the variation width and the solid line shows the center value. . As can be understood from this figure, the pulse count value according to the present invention is J
± for the grain size number (N) measured by the steel ferrite grain size test method specified in IS G 0552.
It is within an error of 0.6, and the crystal grain size can be measured with high accuracy. By performing this measurement over the entire length of the steel pipe P, the grain size distribution over the entire length can be determined.
なお本発明では交流磁化する際、磁気飽和させないのは
次の理由に依る。即ち、従来の方法のように磁気飽和す
るようにして測定した場合には第５図（図中右側の数字
は使用した交流周波数）に示すように周波数が高くなる
と結晶粒度の大小によらずパルス数が一定となり、粒度
測定が不可能である（これが０．２Ｈｚ等、低周波を用
いていた理由である）。これに対して本発明のように磁
気飽和させない場合は、第６図（図中右側の数字は使用
した交流周波数）に示すように５Ｈｚ程度にまで周波数
を高くしてもパルス数が変化して粒度番号を判定できる
。例えば５Ｈｚの場合には、磁化半周期にて測定すると
測定時間は０．１秒で済む。このように測定時間を短縮
できれば１測定期間での測定範囲を狭くでき、測定対象
物の局部的結晶粒度を測定することができるのである；
次に磁気飽和したあと未飽和の状態で測定することの意
義について説明する。一般に製造ライン上にある強磁性
体の磁化状態は一定していない。In addition, in the present invention, the reason why magnetic saturation is not performed during AC magnetization is as follows. In other words, when measuring with magnetic saturation as in the conventional method, as shown in Fig. 5 (the numbers on the right side of the figure are the AC frequencies used), as the frequency increases, the pulse becomes constant regardless of the size of the crystal grain size. The number remains constant, making particle size measurement impossible (this is why a low frequency, such as 0.2 Hz, was used). On the other hand, when magnetic saturation is not achieved as in the present invention, the number of pulses does not change even if the frequency is increased to about 5 Hz, as shown in Figure 6 (the number on the right side of the figure is the AC frequency used). Particle size number can be determined. For example, in the case of 5 Hz, the measurement time is only 0.1 seconds if the measurement is performed in a half cycle of magnetization. If the measurement time can be shortened in this way, the measurement range in one measurement period can be narrowed, and the local grain size of the object to be measured can be measured; next, measurement can be performed in the magnetically saturated and unsaturated state. Explain the significance of Generally, the magnetization state of ferromagnetic materials on a production line is not constant.
即ち電動機或いは着磁された搬送ロール等の磁界発生源
により僅かに磁化されていることが多く、第７図に示す
ように強磁性体内の残留磁束密度がわずかに変化してい
る場合でも未飽和交流磁化（励磁周波数５Ｈｚ）を行い
、磁化２周期当たりに発生するパルス個数を計数すると
・印にあるように同じ結晶粒度であってもパルス数が変
化し、結晶粒度を特定できない。In other words, it is often slightly magnetized by a magnetic field source such as an electric motor or a magnetized transport roll, and as shown in Figure 7, even if the residual magnetic flux density inside the ferromagnetic body changes slightly, it remains unsaturated. When AC magnetization (excitation frequency 5 Hz) is performed and the number of pulses generated per two cycles of magnetization is counted, the number of pulses changes even if the crystal grain size is the same, as shown by the * mark, and the crystal grain size cannot be specified.
一方、本発明の方法、即ち強磁性体を磁気飽和した後、
未飽和交流磁化する方法を行った場合、磁化２周期当た
りに発生するパルス個数の計数値は、第７図（○印）に
示すように初期の強磁性体の磁化状態が変化しても略一
定であり、このため本発明は結晶粒度を正確に検出でき
る。On the other hand, the method of the present invention, that is, after magnetically saturating the ferromagnetic material,
When using the method of unsaturated AC magnetization, the count of the number of pulses generated per two cycles of magnetization remains approximately the same even if the initial magnetization state of the ferromagnetic material changes, as shown in Figure 7 (○ marks). It is constant, and therefore the present invention can accurately detect the grain size.
このことより本発明による場合は直流により磁気飽和す
るまで磁化しているので測定までに既に磁化された磁性
体の磁化状態に影響されることがないのでより正確な検
出ができる。従ってコイル３、コイル４を配する位置は
コイル１による磁場の強さがゼロの位置に限らずある程
度の強さとなっていてもよい。Therefore, in the case of the present invention, since the magnet is magnetized by direct current until it reaches magnetic saturation, it is not affected by the magnetization state of the magnetic material that has already been magnetized before the measurement, so that more accurate detection can be performed. Therefore, the positions at which the coils 3 and 4 are arranged are not limited to positions where the strength of the magnetic field by the coil 1 is zero, but may be at a certain level of strength.
なお上記説明では鋼管の場合での測定であるが、本発明
はこれに限らず他の管状磁性体或いは板状。In the above description, the measurement is performed on a steel pipe, but the present invention is not limited to this, and may be applied to other tubular magnetic bodies or plate-shaped magnetic bodies.
角状、棒状のものであっても測定できることば勿論であ
る。Of course, it is possible to measure even square or rod-shaped objects.
板状のものについては、直流磁化、交流磁化ともその板
材表面での磁力線の方向が板材表面と平行となるように
する。For plate-shaped objects, the direction of the lines of magnetic force on the surface of the plate should be parallel to the surface of the plate in both DC magnetization and AC magnetization.
例えば、第８図２．示すように製造ライン上を白抜矢符
方向の移送さている鋼板ｐｚに対して、上流側の片面側
に磁気飽和用コイル１をその軸心方向が移送方向に一致
するように配し、下流側に検出コイル３と交流磁化用コ
イル４とを、鋼板Ｐ／を挟んで対向するようにまた各軸
心方向が移送方向に一致するように配し、鋼板ＰＲを通
る各コイル１．３．４の磁界の方向が移送方向となるよ
うにコ字状の鉄心１ａ、３ａ、４’ａを各コイル１，３
．４に挿通させ、鉄心１ａ、３ａ、４ａの両磁極面を鋼
板Ｐ／へ向けて設け、第１図の場合と同様にして測定す
る。なお図中において第１図と同一箇所には同一の番号
を符している。For example, Fig. 8 2. As shown, a magnetic saturation coil 1 is arranged on one side of the upstream side of a steel plate pz being transported in the direction of the white arrow on the production line, with its axial direction aligned with the direction of transport, and A detection coil 3 and an AC magnetizing coil 4 are arranged on the sides so as to face each other with the steel plate P/ therebetween, and so that their axial directions coincide with the transfer direction, and each coil 1.3. The U-shaped iron cores 1a, 3a, 4'a are connected to each coil 1, 3 so that the direction of the magnetic field 4 is the transfer direction.
．． 4, the magnetic pole faces of the iron cores 1a, 3a, and 4a are directed toward the steel plate P/, and the measurement is carried out in the same manner as in the case of FIG. Note that in the figure, the same parts as in FIG. 1 are denoted by the same numbers.
以上詳述した如く本発明による場合には磁性体を磁気飽
和させた後未飽和状態で交流磁化するので比較的高い周
波数の交流を使用できると共に残留磁束密度の影響を受
けずにバルクハウゼン雑音を検出でき、このため比較的
高い周波数の使用により測定時間を短縮できると共に精
度の高い測定が可能となる等、本発明は優れた効果を奏
する。As detailed above, in the case of the present invention, since the magnetic material is magnetically saturated and then magnetized with AC in an unsaturated state, relatively high frequency AC can be used, and Barkhausen noise can be suppressed without being affected by residual magnetic flux density. Therefore, the present invention has excellent effects, such as being able to shorten the measurement time by using a relatively high frequency and making it possible to perform highly accurate measurements.
第１図は本発明方法を実施するに好適な装置を示す模式
図、第２図、第３図は夫々磁化履歴、その一部を拡大し
て示すグラフ、第４図は本発明の測定例を示すグラフ、
第５図、第６図は本発明の測定時間の短縮化の説明図、
第７図は本発明の効果を示すグラフ、第８図は本発明の
他の実施例を示す模式図である。
Ｐ・・・鋼管 ｌ・・・磁気飽和用コイル ２・・・直
流電源 ３・・・検出コイル ４・・・交流磁化用コイ
ル９・・・計数器 ＰＩｌ・・・鋼板
時 許 出願人 住友金属工業株式会社代理人 弁理士
河 野 登 夫
竹刀１唇号（ｔ、ｌ） 此夏香号ｃＮ）箒４図 第５図
ｇ ’ｌ １０ ０ ｘ ４ に
趙＆）’！ （Ｎ ） りＩ繊東宏度（Ｇ晦）纂Ｇ図
第７９FIG. 1 is a schematic diagram showing an apparatus suitable for carrying out the method of the present invention, FIGS. 2 and 3 are graphs showing the magnetization history and enlarged portions thereof, and FIG. 4 is a measurement example of the present invention. A graph showing,
FIGS. 5 and 6 are explanatory diagrams of shortening the measurement time of the present invention,
FIG. 7 is a graph showing the effects of the present invention, and FIG. 8 is a schematic diagram showing another embodiment of the present invention. P...Steel pipe l...Magnetic saturation coil 2...DC power supply 3...Detection coil 4...AC magnetization coil 9...Counter PIl...Steel plate time Applicant Sumitomo Metals Kogyo Co., Ltd. Agent Patent Attorney Noboru Kawano Shinai 1 lip number (t, l) Konatsuka number cN) Broom 4 figure 5 figure g 'l 10 0 x 4 ni Zhao&)'! (N) Ri I Sen Higashi Hiroto (G Akira) Compiled G Map
79th
Claims (1)
測定する方法において、前記磁性体を磁気飽和したのち
磁束密度を残留磁束密度又はこれに近いレベルに低減し
、この状態にて磁気飽和させない範囲で交流磁化し、こ
のとき発生するバルクハウゼン雑音の数を計数し、その
計数値より磁性体の結晶粒度を測定することを特徴とす
る結晶粒度測定方法。 ２、移動する磁性体の結晶粒度を測定すべくバルクハウ
ゼン雑音の数を計数する装置において、 前記磁性体を磁気飽和するための直流磁化装置と、 該直流磁化装置よりも磁性体移動方向下流側に配してあ
り、磁性体を磁気飽和させない範囲で交流磁化する交流
磁化装置と、 該交流磁化装置による磁性体の交流磁化部分に臨ませて
配したバルクハウゼン雑音を検出するコイルと、 該コイルにて検出したバルクハウゼン雑音の数を計数す
る計数器と を具備することを特徴とする結晶粒度測定装置。[Claims] 1. In a method of measuring the crystal grain size of a magnetic material based on Barkhausen noise, the magnetic material is magnetically saturated, and then the magnetic flux density is reduced to a residual magnetic flux density or a level close to this, and this state is A crystal grain size measuring method characterized in that AC magnetization is performed within a range that does not cause magnetic saturation, the number of Barkhausen noises generated at this time is counted, and the crystal grain size of a magnetic material is measured from the counted value. 2. A device for counting the number of Barkhausen noises in order to measure the crystal grain size of a moving magnetic body, comprising: a DC magnetization device for magnetically saturating the magnetic body; and a downstream side of the DC magnetization device in the direction of movement of the magnetic body. an alternating current magnetization device that magnetizes the magnetic material with alternating current within a range that does not cause magnetic saturation; a coil that detects Barkhausen noise and is arranged facing the alternating current magnetized portion of the magnetic material by the alternating current magnetization device; and the coil. 1. A crystal grain size measuring device comprising: a counter for counting the number of Barkhausen noises detected in the device.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10404684A JPS60247155A (en) | 1984-05-22 | 1984-05-22 | Method and apparatus for measuring particle size of crystal |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10404684A JPS60247155A (en) | 1984-05-22 | 1984-05-22 | Method and apparatus for measuring particle size of crystal |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS60247155A true JPS60247155A (en) | 1985-12-06 |
Family
ID=14370271
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP10404684A Pending JPS60247155A (en) | 1984-05-22 | 1984-05-22 | Method and apparatus for measuring particle size of crystal |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS60247155A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH01203965A (en) * | 1987-12-22 | 1989-08-16 | Inst Dr F Foerster Pruefgeraet Gmbh | Inspector for material to be inspected made of non-ferromagnetic metal |
| WO1998020335A1 (en) * | 1996-11-07 | 1998-05-14 | Case Technologies Ltd. | Method and apparatus for the on-line measurement of the strength of metal cables |
-
1984
- 1984-05-22 JP JP10404684A patent/JPS60247155A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH01203965A (en) * | 1987-12-22 | 1989-08-16 | Inst Dr F Foerster Pruefgeraet Gmbh | Inspector for material to be inspected made of non-ferromagnetic metal |
| WO1998020335A1 (en) * | 1996-11-07 | 1998-05-14 | Case Technologies Ltd. | Method and apparatus for the on-line measurement of the strength of metal cables |
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