JP2015040746A

JP2015040746A - Electromagnetic ultrasonic sensor, metal material embrittlement evaluation apparatus, and metal material embrittlement evaluation method

Info

Publication number: JP2015040746A
Application number: JP2013171335A
Authority: JP
Inventors: 豊和多田; Toyokazu Tada; 達也楠本; Tatsuya Kusumoto
Original assignee: Sumitomo Chemical Co Ltd
Current assignee: Sumitomo Chemical Co Ltd
Priority date: 2013-08-21
Filing date: 2013-08-21
Publication date: 2015-03-02

Abstract

PROBLEM TO BE SOLVED: To provide an electromagnetic ultrasonic sensor capable of detecting a resonance frequency of a longitudinal ultrasonic wave and a resonance frequency of a transverse ultrasonic wave in one direction, an embrittlement evaluation device and an embrittlement evaluation method.SOLUTION: An electromagnetic ultrasonic sensor 1 is an electromagnetic ultrasonic sensor in which a Halbach array type magnet body 4 is arranged on a coil 3 having a pair of straight line parts A parallel with each other via an opening 2 and wound in a frame shape. The Halbach array type magnet body 4 includes four unit magnets 4a-4d in which the directions of the magnetic fields of the adjacent unit magnets are different from each other and which are juxtaposed in the width direction of the straight line parts A on the opening 2 and the pair of straight line parts A. A width b1 of the opening 2 in the frame-like coil 3 is equal to each width b2 of the pair of straight line parts A, and each width b3 of the unit magnets 4a-4d. Lengths c1 in the coil longitudinal direction of the straight line parts A are longer than lengths c2 of the unit magnets 4a-4d in the same direction. The four unit magnets 4a-4d whose directions of the magnetic fields are different respectively have equal areas overlapping with the frame-like coil 3.

Description

本発明は、脆化した金属材料の脆化程度を評価する電磁超音波センサー、金属材料の脆化評価装置および金属材料の脆化評価方法に関する。 The present invention relates to an electromagnetic ultrasonic sensor, a metal material embrittlement evaluation apparatus, and a metal material embrittlement evaluation method for evaluating the degree of embrittlement of an embrittled metal material.

化学プラントには多種多様な金属材料が使用されているが、使用環境によっては金属材料の様々な脆化が懸念される。例えば、化学プラントの熱交換器伝熱管などに多く用いられている管状部材では、海水などの塩化物環境で耐食性が良い材質として、チタンなどの金属を用いるが、チタンは水素との親和力が大きいために水素を吸収し、その水素を吸収した水素化物部分が脆化することがある。 A wide variety of metal materials are used in chemical plants, but there are concerns about various embrittlement of metal materials depending on the usage environment. For example, tubular members that are often used for heat exchanger tubes in chemical plants use metals such as titanium as materials that have good corrosion resistance in chloride environments such as seawater, but titanium has a high affinity for hydrogen. Therefore, hydrogen is absorbed, and the hydride portion that has absorbed the hydrogen may become brittle.

脆化した水素化物部分は、材料強度が落ちて伝熱管の割れに繋がる可能性がある。このため、プラントの実機に用いられている伝熱管の健全性の確認、すなわち水素化物が生成しているかどうかを確認するために水素濃度を測定する非破壊検査が行われている。 The embrittled hydride portion may lead to cracking of the heat transfer tube due to a decrease in material strength. For this reason, nondestructive inspection for measuring the hydrogen concentration is performed in order to confirm the soundness of the heat transfer tubes used in the actual plant equipment, that is, to confirm whether hydride is generated.

このような水素濃度測定方法として、特許文献１には、図７（ａ）に示すように、両端にそれぞれＳ極とＮ極に磁化させた永久磁石５１の片端に高周波発信用コイルを配置し、同形状の受信用コイルを重ねた構成のコイル５２を有し、縦波超音波（以下、単に縦波という場合がある）と横波超音波（以下、単に横波という場合がある）を同時に発信・受信が可能な機能を有する縦波横波垂直入射型電磁超音波センサー５４、または図７（ｂ）に示すように、互いに磁極が異なるよう二つの永久磁石５５上の各磁石端面の長手方向とコイル５６の直線部が平行となるように配置し、共鳴特性が得られる横波垂直入射型電磁超音波センサー５７を用いて被測定物５３の水素濃度を測定する方法が開示されている。 As such a hydrogen concentration measuring method, in Patent Document 1, as shown in FIG. 7 (a), a high-frequency transmission coil is arranged at one end of a permanent magnet 51 magnetized to S and N poles at both ends, respectively. , Having a coil 52 configured by superimposing reception coils of the same shape, and simultaneously transmitting longitudinal wave ultrasonic waves (hereinafter sometimes simply referred to as longitudinal waves) and transverse wave ultrasonic waves (hereinafter sometimes simply referred to as transverse waves) A longitudinal wave transverse wave perpendicular incidence electromagnetic ultrasonic sensor 54 having a function capable of reception, or the longitudinal direction of each magnet end surface on the two permanent magnets 55 so that the magnetic poles are different from each other as shown in FIG. A method is disclosed in which the hydrogen concentration of the object to be measured 53 is measured using a transverse wave normal incidence electromagnetic ultrasonic sensor 57 that is arranged so that the straight portions of the coil 56 are parallel and obtain resonance characteristics.

一方、被測定物の圧延方向の横波の音速は水素濃度に対してほとんど変化しないが、縦波の音速は水素濃度が高くなるにつれて、ほぼ単調に高くなることが知られている。 On the other hand, it is known that the sound speed of the transverse wave in the rolling direction of the object to be measured hardly changes with respect to the hydrogen concentration, but the sound speed of the longitudinal wave increases substantially monotonically as the hydrogen concentration increases.

特開２００６−２５８５６９号公報JP 2006-2558569 A

本発明者らは、チタン平板中の水素濃度と、縦波とチタン平板の圧延方向の横波との音速比との関係性を調査したところ、チタン平板中の水素濃度と、縦波および圧延方向の横波の音速比とは、図８に示す相関関係があることがわかった。すなわち、縦波の共鳴周波数と一方向の横波の共鳴周波数とを検出すれば、脆化した水素化物部分を特定できることがわかった。 The inventors investigated the relationship between the hydrogen concentration in the titanium plate and the sound speed ratio between the longitudinal wave and the transverse wave in the rolling direction of the titanium plate. The hydrogen concentration in the titanium plate, the longitudinal wave and the rolling direction were investigated. It was found that there is a correlation shown in FIG. That is, it was found that the hydride portion embrittled can be specified by detecting the resonance frequency of the longitudinal wave and the resonance frequency of the transverse wave in one direction.

しかしながら、上述した縦波横波垂直入射型電磁超音波センサー５４では、縦波の共鳴周波数と全方向（主に被測定物の圧延方向と、この方向に対して垂直な方向の２方向）の横波の共鳴周波数を検出するが、縦波の共鳴周波数と横波の共鳴周波数とが近い値を示し共鳴スペクトルが互いに干渉し合う場合があり、このような場合に、共鳴周波数を検出するのが困難となる場合がある。例えば、特許文献１の図３には、共鳴スペクトルが示されているが、この周波数範囲では、縦波の２次共鳴周波数と横波の４次共鳴周波数とがほぼ同じ周波数となり、いずれの共鳴周波数であるかが判別できないという問題がある。
また、上述した横波垂直入射型電磁超音波センサー５７では、一方向の横波の共鳴周波数しか検出できない。 However, in the above-described longitudinal wave transverse wave vertical incidence electromagnetic ultrasonic sensor 54, the longitudinal wave resonance frequency and the transverse wave in all directions (mainly the rolling direction of the object to be measured and two directions perpendicular to this direction). The resonance frequency of the longitudinal wave and the resonance frequency of the transverse wave are close to each other, and the resonance spectrum may interfere with each other. In such a case, it is difficult to detect the resonance frequency. There is a case. For example, FIG. 3 of Patent Document 1 shows a resonance spectrum. In this frequency range, the secondary resonance frequency of the longitudinal wave and the fourth resonance frequency of the transverse wave are substantially the same frequency, and any resonance frequency is obtained. There is a problem that it cannot be determined.
Further, the transverse wave normal incidence electromagnetic ultrasonic sensor 57 described above can detect only the resonance frequency of the transverse wave in one direction.

本発明は、縦波超音波の共鳴周波数と一方向の横波超音波の共鳴周波数とを検出することができる電磁超音波センサー、およびチタンの水素脆化等に代表される金属材料の脆化評価装置ならびに金属材料の脆化評価方法を提供することを目的とする。 The present invention relates to an electromagnetic ultrasonic sensor capable of detecting the resonance frequency of longitudinal ultrasonic waves and the resonance frequency of unidirectional transverse wave ultrasonic waves, and evaluation of embrittlement of metallic materials typified by hydrogen embrittlement of titanium. An object is to provide an apparatus and a method for evaluating embrittlement of a metal material.

本発明者らは、上記課題を解決すべく鋭意研究を重ねた結果、本発明を完成するに至った。すなわち、本発明は、以下の構成からなる。
（１）開口を介して互いに平行な一対の直線部を有し額縁状に巻回されたコイル上に、ハルバッハ配列型磁石体を配置した電磁超音波センサーであって、前記ハルバッハ配列型磁石体は、隣接する単位磁石同士の磁界の向きが互いに異なる少なくとも４個の単位磁石を前記開口と一対の直線部上に前記直線部の幅方向に並設してなり、前記額縁状コイルにおける前記開口部の幅と、前記一対の直線部の各幅と、前記単位磁石の各幅とが等しく、直線部のコイル長手方向の長さが、これと同方向の単位磁石の長さよりも長く、磁界の向きが異なる４つの単位磁石は、それぞれ前記額縁状コイルとの重なり面積が等しいことを特徴とする電磁超音波センサー。
（２）前記ハルバッハ配列型磁石体を、直線部の幅方向にスライドすることができる前記（１）に記載の電磁超音波センサー。
（３）少なくともハルバッハ配列型磁石体上に、ヨークが配置されている前記（１）または（２）に記載の電磁超音波センサー。
（４）被測定物の表面近傍あるいは表面に配置された電磁超音波センサーと、前記電磁超音波センサーに電磁波を発生させる所定周波数の電圧を出力し、前記電磁超音波センサーが一つの測定場所で超音波を受信し、受信した超音波の電気信号を入力する電磁超音波送受信器と、前記被測定物に生じる超音波が共鳴を生じるように前記電磁波超音波送受信器が出力する電圧の周波数を制御するとともに前記電磁波超音波送受信器が入力した超音波の周波数と振幅を記録する制御・記録手段と、前記制御・記録手段に記録された超音波の周波数と振幅から被測定物の共鳴特性指標を算出する共鳴特性指標算出手段と、部材における脆化程度と共鳴特性指標との関係を記憶した標準材データベースと、算出された共鳴特性指標に対応する脆化程度を前記標準材データベースから取得し出力する脆化程度出力手段と、を有する部材の脆化評価装置であって、前記電磁超音波センサーは、前記（１）〜（３）のいずれかに記載の電磁超音波センサーであり、かつ前記共鳴特性指標算出手段は、被測定物の厚さ方向に振動する縦波超音波の共鳴周波数と被測定物の表面に平行な方向に振動する横波超音波の共鳴周波数から共鳴特性指標を算出する、ことを特徴とする部材の脆化評価装置。
（５）前記（１）〜（３）のいずれかに記載の電磁超音波センサーを、被測定物の表面近傍あるいは表面に配置する工程と、電磁超音波センサーにより被測定物に変動磁界を印加する工程と、前記変動磁界により、被測定物の厚さ方向に振動する縦波超音波と、被測定物の表面に平行な方向に振動する横波超音波とを一つの測定場所で受信する工程と、前記縦波超音波が共鳴を生じるように変動磁界の周波数を調整する工程と前記横波超音波が共鳴を生じるように変動磁界の周波数を調整する工程と、前記縦波超音波および前記横波超音波それぞれの共鳴周波数を検出する工程と、検出した前記縦波超音波の共鳴周波数と、検出した前記横波超音波の共鳴周波数に基づいて、被測定物の共鳴特性指標を算出する工程と、予め設定された共鳴特性指標と脆化程度との相関性に基づき、算出された被測定物の共鳴特性指標に対応する脆化程度を決定する工程とを有する脆化評価方法。
（６）電磁超音波センサーを、被測定物の圧延方向と直線部の幅方向とが平行になるように被測定物の表面近傍あるいは表面に配置する前記（５）に記載の脆化評価方法。 As a result of intensive studies to solve the above problems, the present inventors have completed the present invention. That is, this invention consists of the following structures.
(1) An electromagnetic ultrasonic sensor in which a Halbach array type magnet body is disposed on a coil having a pair of linear portions parallel to each other through an opening and wound in a frame shape, the Halbach array type magnet body Is formed by juxtaposing at least four unit magnets having different magnetic field directions between adjacent unit magnets on the opening and a pair of linear portions in the width direction of the linear portion, and the opening in the frame-shaped coil. The width of the portion, the width of each of the pair of straight portions, and the width of each of the unit magnets are equal, and the length of the straight portion in the coil longitudinal direction is longer than the length of the unit magnet in the same direction. The four unit magnets having different directions have the same overlapping area with the frame coil, respectively.
(2) The electromagnetic ultrasonic sensor according to (1), wherein the Halbach array type magnet body can be slid in the width direction of the linear portion.
(3) The electromagnetic ultrasonic sensor according to (1) or (2), wherein a yoke is disposed on at least a Halbach array type magnet body.
(4) An electromagnetic ultrasonic sensor disposed near or on the surface of the object to be measured, and a voltage having a predetermined frequency for generating an electromagnetic wave in the electromagnetic ultrasonic sensor are output, and the electromagnetic ultrasonic sensor is at one measurement place. An electromagnetic ultrasonic transmitter / receiver that receives an ultrasonic wave and inputs an electric signal of the received ultrasonic wave, and a frequency of a voltage output by the electromagnetic wave ultrasonic transmitter / receiver so that the ultrasonic wave generated in the object to be measured generates resonance. Control and recording means for controlling and recording the frequency and amplitude of the ultrasonic wave input by the electromagnetic wave ultrasonic transmitter / receiver, and the resonance characteristic index of the object to be measured from the frequency and amplitude of the ultrasonic wave recorded in the control / recording means Resonance characteristic index calculation means for calculating, a standard material database storing the relationship between the degree of embrittlement in the member and the resonance characteristic index, and the degree of embrittlement corresponding to the calculated resonance characteristic index An embrittlement evaluation apparatus for a member having an embrittlement degree output means that is obtained from the standard material database and outputs the electromagnetic wave sensor, wherein the electromagnetic ultrasonic sensor is an electromagnetic wave according to any one of (1) to (3). The resonance characteristic index calculating means is an ultrasonic sensor, and the resonance characteristic index calculating means is a resonance frequency of longitudinal ultrasonic waves that vibrate in the thickness direction of the object to be measured and resonance of transverse wave ultrasonic waves that vibrate in a direction parallel to the surface of the object to be measured An apparatus for evaluating embrittlement of a member, wherein a resonance characteristic index is calculated from a frequency.
(5) A step of disposing the electromagnetic ultrasonic sensor according to any one of (1) to (3) near or on the surface of the object to be measured, and applying a varying magnetic field to the object to be measured by the electromagnetic ultrasonic sensor. And a step of receiving longitudinal wave ultrasonic waves that vibrate in the thickness direction of the object to be measured and transverse wave ultrasonic waves that vibrate in a direction parallel to the surface of the object to be measured at one measurement location by the varying magnetic field. Adjusting the frequency of the varying magnetic field so that the longitudinal ultrasonic wave causes resonance; adjusting the frequency of the varying magnetic field so that the transverse wave ultrasonic wave causes resonance; and the longitudinal wave ultrasonic wave and the transverse wave Detecting a resonance frequency of each of the ultrasonic waves, calculating a resonance characteristic index of the object to be measured based on the detected resonance frequency of the longitudinal ultrasonic wave and the detected resonance frequency of the transverse wave ultrasonic wave, Preset resonance characteristics Indicators and on the basis of the correlation between the embrittlement approximately, calculated embrittlement evaluation method and a step of determining the embrittlement degree corresponding to the resonant characteristic index of the object to be measured was.
(6) The embrittlement evaluation method according to (5), wherein the electromagnetic ultrasonic sensor is arranged near or on the surface of the object to be measured so that the rolling direction of the object to be measured and the width direction of the linear portion are parallel to each other. .

本発明によれば、縦波の共鳴周波数と一方向の横波の共鳴周波数とを検出することができる。 According to the present invention, the resonance frequency of the longitudinal wave and the resonance frequency of the transverse wave in one direction can be detected.

（ａ）は、本発明の電磁波超音波センサーの一実施形態を示す電磁波超音波センサー１（ヨーク５を除く）を上から見た平面図であり、（ｂ）は、（ａ）中のＸ−Ｘ´線断面図である。(A) is the top view which looked at the electromagnetic wave ultrasonic sensor 1 (except yoke 5) which shows one Embodiment of the electromagnetic wave ultrasonic sensor of this invention from the top, (b) is X in (a). FIG. （ａ）は、単位磁石４ａおよび４ｃが、ちょうど直線部Ａ上に配置された電磁波超音波センサー１（ヨーク５を除く、以下同様）を上から見た平面図であり、（ｂ）は、単位磁石４ｂおよび４ｄが、ちょうど直線部Ａ上に配置された電磁波超音波センサー１の上から見た平面図であり、（ｃ）は、単位磁石４ｃおよび４ｄが、額縁状コイル３の一方の直線部Ａのみに、単位磁石４ｃおよび４ｄのそれぞれと直線部Ａとの重なり面積が等しくなるように、配置された電磁波超音波センサー１の上から見た平面図である。(A) is a plan view of the electromagnetic wave ultrasonic sensor 1 (excluding the yoke 5, the same applies hereinafter) in which the unit magnets 4a and 4c are arranged on the straight line portion A, as viewed from above, (b) The unit magnets 4b and 4d are plan views as seen from above the electromagnetic wave ultrasonic sensor 1 arranged on the straight line portion A. FIG. 5 (c) shows that the unit magnets 4c and 4d are one of the frame coils 3. FIG. 4 is a plan view of the electromagnetic wave ultrasonic sensor 1 arranged from above so that only the straight line portion A has the overlapping areas of the unit magnets 4c and 4d and the straight line portion A equal to each other. 本発明の脆化評価装置の一実施形態の構成とその構成要素間の処理の流れを示す概略図である。It is the schematic which shows the structure of one Embodiment of the embrittlement evaluation apparatus of this invention, and the flow of a process between the component. （ａ）は、実施例１で計測した共鳴スペクトルを示す線図であり、（ｂ）は、比較例１で計測した共鳴スペクトルを示す線図である。(A) is a diagram showing the resonance spectrum measured in Example 1, and (b) is a diagram showing the resonance spectrum measured in Comparative Example 1. （ａ）は、図２（ａ）に示す配置にした電磁波超音波センサーを用いて計測した共鳴スペクトルを示す線図であり、図２（ｂ）に示す配置にした電磁波超音波センサーを用いて計測した共鳴スペクトルを示す線図であり、図２（ｃ）の配置にした電磁波超音波センサーを用いて計測した共鳴スペクトルを示す線図である。(A) is a diagram which shows the resonance spectrum measured using the electromagnetic wave ultrasonic sensor arranged in FIG. 2 (a), and uses the electromagnetic wave ultrasonic sensor arranged in FIG. 2 (b). It is a diagram which shows the measured resonance spectrum, and is a diagram which shows the resonance spectrum measured using the electromagnetic wave ultrasonic sensor arrange | positioned at FIG.2 (c). 実施例２で計測した二相ステンレス鋼（SUS329J4L）平板のシャルピー衝撃値に対する、二相ステンレス鋼平板の縦波と圧延方向の横波との音速比を示すグラフである。It is a graph which shows the sound speed ratio of the longitudinal wave of a duplex stainless steel flat plate, and the transverse wave of a rolling direction with respect to the Charpy impact value of the duplex stainless steel (SUS329J4L) flat plate measured in Example 2. FIG. （ａ）公知の縦波横波垂直入射型電磁超音波センサーの斜視図であり、（ｂ）は、公知の横波垂直入射型電磁超音波センサーの斜視図である。(A) It is a perspective view of a well-known longitudinal wave transverse wave perpendicular | vertical incidence type electromagnetic ultrasonic sensor, (b) is a perspective view of a well-known transverse wave perpendicular | vertical incidence type electromagnetic ultrasonic sensor. チタン平板中の水素濃度に対する、縦波と圧延方向の横波の音速比を示すグラフである。It is a graph which shows the sound speed ratio of the longitudinal wave and the transverse wave of a rolling direction with respect to the hydrogen concentration in a titanium flat plate.

以下、本発明の電磁超音波センサーの一実施形態について、図面を参照して詳細に説明する。 Hereinafter, an embodiment of an electromagnetic ultrasonic sensor of the present invention will be described in detail with reference to the drawings.

（電磁波超音波センサー１）
図１（ａ）は、本発明の電磁波超音波センサーの一実施形態を示す電磁波超音波センサー１（ヨーク５を除く）を上から見た平面図であり、図１（ｂ）は、図１（ａ）中のＸ−Ｘ´線断面図である。なお、図１（ａ）において、点（・）および印（×）は単位磁石の磁界の方向を示す矢印の矢の方向を示す。また、図１（ｂ）において、点（・）および印（×）は電流の方向を示す矢印の矢の方向を示し、中抜き矢印は過電流７がハルバッハ配列型磁石体４から受ける磁界の向きを示している。 (Electromagnetic wave ultrasonic sensor 1)
Fig.1 (a) is the top view which looked at the electromagnetic wave ultrasonic sensor 1 (except yoke 5) which shows one Embodiment of the electromagnetic wave ultrasonic sensor of this invention from the top, FIG.1 (b) is FIG. It is XX 'sectional view taken on the line in (a). In FIG. 1A, a point (•) and a mark (×) indicate the direction of the arrow of the arrow indicating the direction of the magnetic field of the unit magnet. In FIG. 1B, the point (•) and the mark (×) indicate the direction of the arrow indicating the direction of the current, and the hollow arrow indicates the magnetic field that the overcurrent 7 receives from the Halbach array type magnet body 4. Indicates the direction.

電磁波超音波センサー１は、図１に示すように、開口部２を介して互いに平行な一対の直線部Ａを有し額縁状に巻回されたコイル３と、この額縁状コイル３上に配置されたハルバッハ配列型磁石体４と、ハルバッハ配列型磁石体４上に配置されたヨーク５とからなる。
ハルバッハ配列型磁石体４は、隣接する単位磁石４ａ〜４ｄ同士の磁界の向きが互いに異なる４個の単位磁石４ａ〜４ｄを開口部２と一対の直線部Ａ上に直線部Ａの幅方向に一本状に並設されたものである。
また、額縁状コイル３における開口部２の幅ｂ１と、額縁状コイル３における一対の直線部Ａの各幅ｂ２と、単位磁石４ａ〜４ｄの各幅ｂ３とは互いに等しく、直線部Ａのコイル長手方向の長さｃ１は、これと同方向の単位磁石の長さｃ２よりも長い。
磁界の向きが異なる４つの単位磁石４ａ〜４ｄは、それぞれ額縁状コイル３の直線部Ａとの重なり面積が等しくなるように、すなわち、図１（ａ）に示すように、Ｙ−Ｙ´線に対して対称となるようにハルバッハ配列型磁石体４は額縁状コイル３上に配置されている。
電磁波超音波センサー１は、上記のように構成されるので、後述する脆化評価装置により被測定物６内の脆化程度を測定する際、被測定物６内の縦波と直線部Ａの幅方向の横波の共鳴周波数が判別しやすく、脆化部分を特定しやすい。 As shown in FIG. 1, the electromagnetic wave ultrasonic sensor 1 includes a coil 3 having a pair of straight portions A parallel to each other through an opening 2 and wound in a frame shape, and is disposed on the frame-shaped coil 3. The Halbach arrayed magnet body 4 and a yoke 5 disposed on the Halbach array magnet body 4 are provided.
In the Halbach array type magnet body 4, four unit magnets 4 a to 4 d having different magnetic field directions between adjacent unit magnets 4 a to 4 d are arranged on the opening 2 and the pair of straight portions A in the width direction of the straight portion A. They are arranged in a single line.
The width b1 of the opening 2 in the frame-shaped coil 3, the width b2 of the pair of linear portions A in the frame-shaped coil 3, and the width b3 of the unit magnets 4a to 4d are equal to each other. The length c1 in the longitudinal direction is longer than the length c2 of the unit magnet in the same direction.
The four unit magnets 4a to 4d having different magnetic field directions have the same overlapping area with the straight line portion A of the frame coil 3, that is, as shown in FIG. Are arranged on the frame-like coil 3 so as to be symmetrical with respect to the frame.
Since the electromagnetic wave ultrasonic sensor 1 is configured as described above, when the degree of embrittlement in the measurement object 6 is measured by the embrittlement evaluation apparatus described later, the longitudinal wave in the measurement object 6 and the linear portion A are measured. The resonance frequency of the transverse wave in the width direction can be easily identified, and the embrittled portion can be easily identified.

電磁波超音波センサー１は、図１（ｂ）に示すように、額縁状コイル３に交流またはパルス状の高周波数電流が給電されると、電磁誘導により被測定物６内に過電流７を発生させる。この発生された過電流７と、ハルバッハ配列型磁石体４によって加えられる磁界とのローレンツ力により被測定物６内に超音波が発生し、この超音波（発信波）と跳ね返ってきた超音波（反射波）とが一致する周波数、並びにその整数倍の周波数のときに共鳴が起こる。発信波および反射波が一致したときに発生する共鳴波により、被測定物６では、額縁状コイル３に対向する部分に起電力が励起され、この起電力により発生する電磁波が額縁状コイル３に受信されて誘導電流を発生することで、共鳴を受信することができる。 As shown in FIG. 1B, the electromagnetic wave ultrasonic sensor 1 generates an overcurrent 7 in the measured object 6 by electromagnetic induction when an alternating current or pulsed high frequency current is supplied to the frame coil 3. Let An ultrasonic wave is generated in the measurement object 6 by the Lorentz force between the generated overcurrent 7 and the magnetic field applied by the Halbach array type magnet body 4, and this ultrasonic wave (transmitted wave) and the ultrasonic wave bounced back ( Resonance occurs at a frequency that coincides with the (reflected wave) and an integer multiple of the frequency. An electromotive force is excited in a portion of the DUT 6 facing the frame-shaped coil 3 by a resonance wave generated when the transmitted wave and the reflected wave coincide with each other, and an electromagnetic wave generated by the electromotive force is generated in the frame-shaped coil 3. Resonance can be received by receiving and generating an induced current.

電磁波超音波センサー１は、例えば、図２（ａ）〜（ｃ）に示すように、直線部Ａの幅方向に、ハルバッハ配列型磁石体４をスライドさせることができる。
図２（ａ）は、ハルバッハ配列型磁石体４をスライドさせて、単位磁石４ａおよび４ｃが、ちょうど直線部Ａ上に配置された電磁波超音波センサー１を示す。このようにハルバッハ配列型磁石体４を配置することで、被測定物６の縦波の共鳴周波数が判別しやすくなる。
図２（ｂ）は、ハルバッハ配列型磁石体４をスライドさせて、単位磁石４ｂおよび４ｄが、ちょうど直線部Ａ上に配置された電磁波超音波センサー１を示す。このようにハルバッハ配列型磁石体４を配置することで、直線部Ａの幅方向の横波の共鳴周波数が判別しやすくなる。
図２（ｃ）は、ハルバッハ配列型磁石体４をスライドさせて、単位磁石４ｃおよび４ｄが、額縁状コイル３の一方の直線部Ａのみに、単位磁石４ｃおよび４ｄのそれぞれと直線部Ａとの重なり面積が等しくなるように、配置された電磁波超音波センサー１を示す。このようにハルバッハ配列型磁石体４を配置させても、縦波および直線部Ａの幅方向の横波ともに十分強い信号で共鳴スペクトルが得られるので、簡単な構成の電磁波超音波センサーで、局所的な金属材料の脆化評価が可能となる。 The electromagnetic wave ultrasonic sensor 1 can slide the Halbach array type magnet body 4 in the width direction of the linear portion A, for example, as shown in FIGS.
FIG. 2A shows the electromagnetic wave ultrasonic sensor 1 in which the unit magnets 4 a and 4 c are arranged on the straight line portion A by sliding the Halbach array type magnet body 4. By arranging the Halbach array type magnet body 4 in this way, the resonance frequency of the longitudinal wave of the DUT 6 can be easily identified.
FIG. 2B shows the electromagnetic wave ultrasonic sensor 1 in which the unit magnets 4 b and 4 d are arranged on the straight line portion A by sliding the Halbach array type magnet body 4. By arranging the Halbach array type magnet body 4 in this way, the resonance frequency of the transverse wave in the width direction of the straight portion A can be easily determined.
In FIG. 2C, the Halbach array type magnet body 4 is slid so that the unit magnets 4c and 4d are arranged only on one linear part A of the frame-shaped coil 3 and the linear part A and the unit magnets 4c and 4d. The electromagnetic wave ultrasonic sensors 1 are shown so that their overlapping areas are equal. Even when the Halbach array type magnet body 4 is arranged in this way, a resonance spectrum can be obtained with sufficiently strong signals for both the longitudinal wave and the transverse wave in the width direction of the straight line portion A. Therefore, an electromagnetic wave ultrasonic sensor with a simple configuration can be used locally. It is possible to evaluate embrittlement of a simple metal material.

（額縁状コイル３）
額縁状コイル３の寸法は、特に限定されず、外寸が10.0〜200mm×6.0〜120mm×0.02〜1.0mmtである。開口部２の寸法は、直線部Ａのコイル長手方向の長さｃ１が6.0〜120mmであり、開口部２の幅ｂ１が2.0〜40.0mmであればよい。 (Frame-shaped coil 3)
The dimension of the frame-shaped coil 3 is not particularly limited, and the outer dimension is 10.0 to 200 mm × 6.0 to 120 mm × 0.02 to 1.0 mmt. The dimension of the opening 2 may be such that the length c1 of the linear portion A in the longitudinal direction of the coil is 6.0 to 120 mm and the width b1 of the opening 2 is 2.0 to 40.0 mm.

コイルを形成する巻線としては、特に限定されず、例えば、エナメル線、ポリウレタン線、ポリエステル線、シリコーン線、テフロン（登録商標）線、ポリアミド・イミド線などが挙げられる。
巻線の断面形状は、特に限定されず、例えば、円形、四角、三角などが挙げられる。
巻線の直径は、特に限定されず、0.02〜1.0mmである。 The winding that forms the coil is not particularly limited, and examples thereof include enameled wire, polyurethane wire, polyester wire, silicone wire, Teflon (registered trademark) wire, and polyamide / imide wire.
The cross-sectional shape of the winding is not particularly limited, and examples thereof include a circle, a square, and a triangle.
The diameter of the winding is not particularly limited and is 0.02 to 1.0 mm.

（ハルバッハ配列型磁石体４）
単位磁石４ａ〜４ｄの材質としては、ネオジム磁石などの高性能永久磁石などが挙げられる。
単位磁石４ａ〜４ｄの形状は、例えば、直方体や立方体などであればよい。
単位磁石４ａ〜４ｄの寸法は、幅ｂ３が開口部２の幅ｂ１と等しく、長さｃ２が、2.0〜80.0mmであり、高さは2.0〜40.0mmである。 (Halbach array type magnet body 4)
Examples of the material of the unit magnets 4a to 4d include high-performance permanent magnets such as neodymium magnets.
The shape of the unit magnets 4a to 4d may be, for example, a rectangular parallelepiped or a cube.
As for the dimensions of the unit magnets 4a to 4d, the width b3 is equal to the width b1 of the opening 2, the length c2 is 2.0 to 80.0 mm, and the height is 2.0 to 40.0 mm.

なお、本実施形態では、隣接する単位磁石同士の磁界の向きが互いに異なる４個の単位磁石４ａ〜４ｄを開口部２と一対の直線部Ａ上に直線部Ａの幅方向に一本状に並設されたハルバッハ配列型磁石体４を用いたが、本発明では、隣接する単位磁石同士の磁界の向きが互いに異なる５個以上の単位磁石を開口２と一対の直線部Ａ上に直線部Ａの幅方向に一本状に並設されたハルバッハ配列型磁石体を用いてもよい。 In the present embodiment, four unit magnets 4a to 4d in which the direction of the magnetic field between adjacent unit magnets are different from each other are formed in a single shape in the width direction of the straight portion A on the opening 2 and the pair of straight portions A. Although the Halbach arrayed magnet bodies 4 arranged side by side are used, in the present invention, five or more unit magnets having different magnetic field directions between adjacent unit magnets are arranged on the opening 2 and the pair of straight portions A. A Halbach array type magnet body arranged in a line in the width direction of A may be used.

（ヨーク５）
ヨーク５の材質としては、炭素鋼、低合金鋼などの高透磁率金属が用いられる。
ヨーク５の大きさは、図１（ｂ）に示すように、ハルバッハ配列型磁石体４の上面を全て覆うサイズであればよく、厚みは0.5〜20.0mmであればよい。 (York 5)
As the material of the yoke 5, a high permeability metal such as carbon steel or low alloy steel is used.
As shown in FIG. 1B, the yoke 5 may have a size that covers the entire top surface of the Halbach array type magnet body 4 and may have a thickness of 0.5 to 20.0 mm.

なお、本実施形態では、ハルバッハ配列型磁石体４の上面のみを覆うヨーク５を用いたが、本発明では、ヨークを備えることは必須ではない。 In this embodiment, the yoke 5 that covers only the upper surface of the Halbach array magnet body 4 is used. However, in the present invention, it is not essential to provide the yoke.

被測定物６としては、例えば、チタン；マルテンサイト系、フェライト系、オーステナイト系、オーステナイト・フェライト系、析出硬化系などのステンレス鋼；ジルコニウム；タンタルなどの金属からなる管状部材、板状部材などが挙げられる。
被測定物６の厚みは、0.5〜10.0mm程度が好ましい。 Examples of the object to be measured 6 include titanium; stainless steel such as martensite, ferrite, austenite, austenite / ferrite, and precipitation hardening; zirconium; a tubular member made of a metal such as tantalum; Can be mentioned.
The thickness of the DUT 6 is preferably about 0.5 to 10.0 mm.

以下、本発明の金属材料の脆化評価装置および金属材料の脆化評価方法の一実施形態について、図面を参照にして詳細に説明する。 Hereinafter, an embodiment of a metal material embrittlement evaluation apparatus and a metal material embrittlement evaluation method of the present invention will be described in detail with reference to the drawings.

（金属材料の脆化評価装置）
図３は、電磁波超音波センサー１を用いた金属材料の脆化評価装置の一実施形態の構成とその構成要素間の処理の流れを示している。 (Metallic material embrittlement evaluation system)
FIG. 3 shows a configuration of an embodiment of a metal material embrittlement evaluation apparatus using the electromagnetic wave ultrasonic sensor 1 and a flow of processing between the components.

本実施形態に係る金属材料の脆化評価装置は、電磁超音波センサー１と、電磁超音波送受信器と、制御・記録手段と、共鳴特性指標算出手段と、脆化程度出力手段と、標準材データベースとを有している。 The metal material embrittlement evaluation apparatus according to the present embodiment includes an electromagnetic ultrasonic sensor 1, an electromagnetic ultrasonic transmitter / receiver, a control / recording means, a resonance characteristic index calculating means, an embrittlement degree output means, and a standard material. And a database.

本実施形態に係る金属材料の脆化評価装置による被測定物６中の脆化程度の測定は以下のように行われる。 The measurement of the degree of embrittlement in the measurement object 6 by the metal material embrittlement evaluation apparatus according to the present embodiment is performed as follows.

電磁超音波センサー１は、被測定物６の壁体表面あるいはその近傍に配置される。
この際、電磁超音波センサー１を、被測定物６の圧延方向と直線部の幅方向とが平行になるように被測定物の表面近傍あるいは表面に配置するのが好ましい。これにより、被測定物６の厚み方向の縦波と、被測定物６の圧延方向の横波とを測定することができる。 The electromagnetic ultrasonic sensor 1 is disposed on the surface of the wall of the object to be measured 6 or in the vicinity thereof.
At this time, it is preferable to arrange the electromagnetic ultrasonic sensor 1 in the vicinity of the surface of the object to be measured or on the surface so that the rolling direction of the object to be measured 6 and the width direction of the linear portion are parallel to each other. Thereby, a longitudinal wave in the thickness direction of the DUT 6 and a transverse wave in the rolling direction of the DUT 6 can be measured.

次に、変化する磁界と超音波の送受信工程が行われる。最初に、制御・記録手段が、被測定物６に縦波と横波の共鳴状態を生じさせるように、電磁波超音波送受信器に電磁超音波送受信器の出力電圧の周波数の制御信号を出力する。この制御信号により、電磁超音波送受信器は電磁超音波センサー１に変化する電圧を出力し、電磁超音波センサーに磁束密度が高周波で変化する磁界を生じさせる。被測定物６近傍で磁束密度が高周波で変化することにより、被測定物は縦波と横波を生じる。電磁超音波センサー１は被測定物６の一つの測定場所で生じた縦波と横波を受信し、電磁超音波送受信器に出力する。電磁超音波送受信器は受信した縦波と横波の信号を制御・記録手段に送り、制御・記録手段はこの縦波と横波の信号を記録する。 Next, a transmitting / receiving process of changing magnetic fields and ultrasonic waves is performed. First, the control / recording means outputs a control signal of the frequency of the output voltage of the electromagnetic wave ultrasonic transmitter / receiver to the electromagnetic wave ultrasonic wave transmitter / receiver so as to generate a longitudinal wave and a transverse wave resonance state in the DUT 6. By this control signal, the electromagnetic ultrasonic transmitter / receiver outputs a voltage that changes to the electromagnetic ultrasonic sensor 1, and generates a magnetic field in which the magnetic flux density changes at a high frequency in the electromagnetic ultrasonic sensor. When the magnetic flux density changes at a high frequency in the vicinity of the device under test 6, the device under test generates a longitudinal wave and a transverse wave. The electromagnetic ultrasonic sensor 1 receives a longitudinal wave and a transverse wave generated at one measurement location of the object to be measured 6 and outputs them to the electromagnetic ultrasonic transmitter / receiver. The electromagnetic ultrasonic transmitter / receiver sends the received longitudinal and transverse signals to the control / recording means, and the control / recording means records the longitudinal and transverse signals.

次に、共鳴特性指標算出手段は、制御・記録手段から電磁超音波センサー１が受信した縦波と横波の信号を入力し、縦波の共鳴周波数と横波の共鳴周波数を検出し、縦波の共鳴周波数と横波の共鳴周波数とを使用して共鳴特性指標を算出する。該共鳴特性指標は、被測定物の脆化程度と相関関係を有するものである。 Next, the resonance characteristic index calculation means receives the longitudinal wave and transverse wave signals received by the electromagnetic ultrasonic sensor 1 from the control / recording means, detects the longitudinal resonance frequency and the transverse resonance frequency, and detects the longitudinal wave resonance frequency. A resonance characteristic index is calculated using the resonance frequency and the resonance frequency of the transverse wave. The resonance characteristic index has a correlation with the degree of embrittlement of the object to be measured.

次に、脆化程度出力手段は、共鳴特性指標算出手段から共鳴特性指標を入力し、標準材データベースを参照する。標準材データベースには、被測定物６と同一部材仕様の部材における共鳴特性指標と脆化程度が対応付けられて記憶されている。脆化程度出力手段は、標準材データベースに記憶されている共鳴特性指標と対応する脆化程度を検索し、該脆化程度を出力する。 Next, the embrittlement degree output means inputs the resonance characteristic index from the resonance characteristic index calculation means, and refers to the standard material database. In the standard material database, the resonance characteristic index and the degree of embrittlement in a member having the same member specifications as the object to be measured 6 are stored in association with each other. The embrittlement degree output means searches for the degree of embrittlement corresponding to the resonance characteristic index stored in the standard material database, and outputs the degree of embrittlement.

上記操作により、被測定物６の一つの測定場所での脆化程度を求めることができる。これにより、例えば、プラントの実機に用いられている伝熱管の脆化した水素化物部分を容易に特定することができたり、475℃脆化等の脆化程度を容易に評価することができる。 By the above operation, the degree of embrittlement at one measurement location of the DUT 6 can be obtained. As a result, for example, an embrittled hydride portion of a heat transfer tube used in an actual plant can be easily identified, and the degree of embrittlement such as 475 ° C. embrittlement can be easily evaluated.

なお、同一の部材仕様の部材とは、寸法、材質、製造方法等の部材仕様が同一の部材である。製造ロットや部材中の部位が相違しても部材仕様が同一であれば同一部材仕様の部材ということができる。 The members having the same member specifications are members having the same member specifications such as dimensions, materials, and manufacturing methods. Even if the production lots and parts in the members are different, it can be said that the members have the same member specifications if the member specifications are the same.

以下、本発明の実施例を示すが、本発明はこれらによって限定されるものではない。 Examples of the present invention will be described below, but the present invention is not limited thereto.

（実施例１）
＜電磁超音波センサー＞
電磁超音波センサーは、図１に示す構成のものを用いた。額縁状コイル３として、外寸が23.0mm×15.0mm×0.7mmtで、開口部２が、直線部Ａのコイル長手方向の長さＣ１が14.0mmであり、開口部２の幅ｂ１が5.0mmであるエナメル線を巻回した額縁状コイルを用いた。単位磁石４ａ〜４ｄとして、幅ｂ３が開口部２の幅ｂ１と等しく、コイル長手方向の長さｃ２が、9.0mmであり、高さ12.0mmである、材質がネオジウムからなる磁石を用いた。ヨーク５として、ハルバッハ配列型磁石体４の上面を全て覆い、厚みが5.0mmである、S15Cからなるヨークを用いた。 Example 1
<Electromagnetic ultrasonic sensor>
The electromagnetic ultrasonic sensor having the configuration shown in FIG. 1 was used. The frame-shaped coil 3 has an outer dimension of 23.0 mm × 15.0 mm × 0.7 mmt, the opening 2 has a length C1 of the linear portion A in the longitudinal direction of the coil of 14.0 mm, and the width b1 of the opening 2 is 5.0 mm. A frame-shaped coil wound with an enameled wire was used. As the unit magnets 4a to 4d, magnets made of neodymium having a width b3 equal to the width b1 of the opening 2, a length c2 in the coil longitudinal direction of 9.0 mm, and a height of 12.0 mm were used. As the yoke 5, a yoke made of S15C, which covers the entire upper surface of the Halbach arrayed magnet body 4 and has a thickness of 5.0 mm, was used.

電磁超音波センサーを、チタン平板試験体（TP340H、寸法：60.0mm×200mm×2.0mmt）の圧延方向と直線部の幅方向とが平行になるように平板試験体上に配置し、この配置した部位について、電磁超音波送受信器（RITEC社製の「RAM-5000」）で、バースト波の時間幅80μｓ、測定周波数間隔（分解能）4.5ｋＨｚとし、周波数１〜１０ＭＨｚ間で掃引して共鳴スペクトルを得た。その結果を図４（ａ）に示す。
また、電磁超音波センサーを図２（ａ）に示す配置とした他は実施例１と同様にして、共鳴スペクトルを得た。その結果を図４（ａ）に示す。電磁超音波センサーを図２（ｂ）に示す配置とした場合、図２（ｃ）に示す配置とした場合についても同様に共鳴スペクトルを得、それぞれの結果を図４（ｂ）、（ｃ）に示す。 An electromagnetic ultrasonic sensor was placed on the flat plate specimen so that the rolling direction of the titanium flat specimen (TP340H, dimensions: 60.0 mm x 200 mm x 2.0 mmt) and the width direction of the straight line portion were parallel to each other. With respect to the site, the resonance spectrum is obtained by sweeping between 1 to 10 MHz with an electromagnetic ultrasonic transmitter / receiver (“RAM-5000” manufactured by RITEC) with a burst wave time width of 80 μs and a measurement frequency interval (resolution) of 4.5 kHz. Obtained. The result is shown in FIG.
Further, a resonance spectrum was obtained in the same manner as in Example 1 except that the electromagnetic ultrasonic sensor was arranged as shown in FIG. The result is shown in FIG. When the electromagnetic ultrasonic sensor is arranged as shown in FIG. 2B, the resonance spectrum is obtained in the same manner as in the arrangement shown in FIG. 2C, and the results are shown in FIGS. 4B and 4C. Shown in

（比較例１）
電磁超音波センサー１の代わりに、下記の縦波横波垂直入射型電磁超音波センサーを用いた他は実施例１と同様にして、共鳴スペクトルを得た。その結果を図４（ｂ）に示す。 (Comparative Example 1)
A resonance spectrum was obtained in the same manner as in Example 1 except that instead of the electromagnetic ultrasonic sensor 1, the following longitudinal wave transverse wave vertical incidence electromagnetic ultrasonic sensor was used. The result is shown in FIG.

なお、縦波横波垂直入射型電磁超音波センサーは、図７（ａ）に示す構成のものを用いた。コイル５２として、直径が20.0mmで、厚みが0.3mmであるエナメル線を巻回した円形状コイルを用いた。永久磁石５１として、直径が15.0mmで、高さが10.0mmである、材質がネオジウムからなる円柱形磁石を用いた。 In addition, the thing of the structure shown to Fig.7 (a) was used for the longitudinal wave transverse wave perpendicular | vertical incident type electromagnetic ultrasonic sensor. As the coil 52, a circular coil wound with an enameled wire having a diameter of 20.0 mm and a thickness of 0.3 mm was used. As the permanent magnet 51, a cylindrical magnet having a diameter of 15.0 mm and a height of 10.0 mm and made of neodymium is used.

図４に示すように、比較例１では、縦波超音波の共鳴周波数、平板試験体の圧延方向の横波超音波（横波１）の共鳴周波数およびこの方向に対して垂直な方向の横波超音波（横波２）の共鳴周波数を検出したのに対して、実施例１では、縦波超音波の共鳴周波数および平板試験体の横波１の共鳴周波数のみを検出した。さらに、比較例１に比べて実施例１の横波１の共鳴スペクトルのピークが高かった。
また、図５（ａ）に示すように、図２（ａ）に示す配置の電磁超音波センサーを用いると、縦波超音波のみの共鳴スペクトルが得られた。図５（ｂ）に示すように、図２（ｂ）に示す配置の電磁超音波センサーを用いると、平板試験体の圧延方向の横波波超音波のみの共鳴スペクトルが得られた。図５（ｃ）に示すように、図２（ｃ）に示す配置の電磁超音波センサーを用いても、縦波超音波および平板試験体の圧延方向の横波波超音波の共鳴スペクトルが得られた。 As shown in FIG. 4, in Comparative Example 1, the resonance frequency of longitudinal ultrasonic waves, the resonance frequency of transverse wave ultrasonic waves (lateral wave 1) in the rolling direction of the plate specimen, and the transverse wave ultrasonic waves in a direction perpendicular to this direction. Whereas the resonance frequency of (lateral wave 2) was detected, in Example 1, only the resonance frequency of longitudinal ultrasonic waves and the resonance frequency of transverse wave 1 of the flat plate specimen were detected. Furthermore, the peak of the resonance spectrum of the transverse wave 1 of Example 1 was higher than that of Comparative Example 1.
Further, as shown in FIG. 5 (a), when the electromagnetic ultrasonic sensor having the arrangement shown in FIG. 2 (a) was used, a resonance spectrum of only longitudinal ultrasonic waves was obtained. As shown in FIG. 5 (b), when the electromagnetic ultrasonic sensor having the arrangement shown in FIG. 2 (b) was used, a resonance spectrum of only the transverse wave ultrasonic waves in the rolling direction of the flat plate specimen was obtained. As shown in FIG. 5 (c), the resonance spectrum of the longitudinal ultrasonic wave and the transverse wave ultrasonic wave in the rolling direction of the flat plate specimen can be obtained even by using the electromagnetic ultrasonic sensor arranged as shown in FIG. 2 (c). It was.

（実施例２）
SUS329J4Lに代表される二相ステンレス鋼は強度や耐食性に優れるため、高い耐食性が要求される多くの機器に使用されている。しかしながら、二相ステンレス鋼は300〜550℃での熱時効によって脆化するという欠点を持ち、実機においても熱時効による脆化が問題となっている。そこで、二相ステンレス鋼（SUS329J4L）平板を熱処理して人工的に475℃脆化を生じさせ、電磁超音波共鳴法による脆化程度の評価が可能であるか検討を行った。
尚、脆化度合いは、475℃脆化を生じさせた二相ステンレス鋼平板をサブサイズシャルピー衝撃試験片（Vノッチ、55 mm×7.5 mm×10 mmt）に加工し、これを用いた室温でのシャルピー衝撃試験によって定量的に計測した。また、縦波の音速と横波の音速は、475℃脆化を生じさせた二相ステンレス鋼平板（100 mm×90 mm×9.0 mmt）について、実施例１で用いた電磁超音波センサー１を用いて、実施例1と同様にして計測した。その結果を図６に示す。この結果、SUS329J4Lの475℃脆化でも本手法が有効であることが確認された。 (Example 2)
Duplex stainless steel represented by SUS329J4L has excellent strength and corrosion resistance, and is used in many devices that require high corrosion resistance. However, duplex stainless steel has the disadvantage of becoming brittle by thermal aging at 300 to 550 ° C., and embrittlement due to thermal aging is a problem even in actual machines. Therefore, we investigated whether it is possible to evaluate the degree of embrittlement by electromagnetic ultrasonic resonance method by artificially causing embrittlement at 475 ° C by heat treating a duplex stainless steel (SUS329J4L) flat plate.
The degree of embrittlement was measured at room temperature using a sub-size Charpy impact test piece (V notch, 55 mm x 7.5 mm x 10 mmt), which was made from a duplex stainless steel plate that had been embrittled at 475 ° C. Quantitatively measured by Charpy impact test. In addition, the acoustic velocity of the longitudinal wave and the acoustic velocity of the transverse wave were measured using the electromagnetic ultrasonic sensor 1 used in Example 1 for a duplex stainless steel flat plate (100 mm × 90 mm × 9.0 mmt) that was embrittled at 475 ° C. Thus, measurement was performed in the same manner as in Example 1. The result is shown in FIG. As a result, it was confirmed that this method is effective even for 475 ° C embrittlement of SUS329J4L.

１、５４、５７電磁超音波センサー
２開口部
３額縁状コイル
４ハルバッハ配列型磁石体
５ヨーク
６被測定物
７渦電流
５１、５５永久磁石
５２、５６コイル DESCRIPTION OF SYMBOLS 1, 54, 57 Electromagnetic ultrasonic sensor 2 Opening part 3 Frame-shaped coil 4 Halbach array type magnet body 5 Yoke 6 Measured object 7 Eddy current 51, 55 Permanent magnet 52, 56 Coil

Claims

An electromagnetic ultrasonic sensor in which a Halbach array type magnet body is arranged on a coil having a pair of linear portions parallel to each other through an opening and wound in a frame shape,
The Halbach array type magnet body includes at least four unit magnets having different magnetic field directions between adjacent unit magnets arranged in parallel in the width direction of the linear portion on the opening and the pair of linear portions,
The width of the opening in the frame-shaped coil, each width of the pair of linear portions, and each width of the unit magnet are equal,
The length of the linear portion in the coil longitudinal direction is longer than the length of the unit magnet in the same direction as this,
The electromagnetic ultrasonic sensor according to claim 4, wherein the four unit magnets having different magnetic field directions have the same overlapping area with the frame coil.

The electromagnetic ultrasonic sensor according to claim 1, wherein the Halbach array type magnet body can be slid in a width direction of the linear portion.

The electromagnetic ultrasonic sensor according to claim 1, wherein a yoke is disposed at least on the Halbach array type magnet body.

An electromagnetic ultrasonic sensor disposed near or on the surface of the object to be measured;
An electromagnetic ultrasonic transmitter / receiver that outputs a voltage of a predetermined frequency that generates electromagnetic waves in the electromagnetic ultrasonic sensor, the ultrasonic ultrasonic sensor receives ultrasonic waves at one measurement location, and inputs an electric signal of the received ultrasonic waves When,
Control that records the frequency and amplitude of the ultrasonic wave input by the electromagnetic wave ultrasonic transmitter / receiver while controlling the frequency of the voltage output by the electromagnetic wave ultrasonic wave transmitter / receiver so that the ultrasonic wave generated in the object to be measured causes resonance. Recording means;
Resonance characteristic index calculating means for calculating the resonance characteristic index of the object to be measured from the frequency and amplitude of the ultrasonic waves recorded in the control / recording means;
A standard material database that stores the relationship between the degree of embrittlement in the member and the resonance characteristic index;
An embrittlement degree output unit that acquires and outputs the degree of embrittlement corresponding to the calculated resonance characteristic index from the standard material database,
The electromagnetic ultrasonic sensor is the electromagnetic ultrasonic sensor according to any one of claims 1 to 3,
The resonance characteristic index calculating means calculates the resonance characteristic index from the resonance frequency of longitudinal ultrasonic waves that vibrate in the thickness direction of the object to be measured and the resonance frequency of transverse wave ultrasonic waves that vibrate in a direction parallel to the surface of the object to be measured. A member embrittlement evaluation apparatus characterized by calculating.

A step of arranging the electromagnetic ultrasonic sensor according to any one of claims 1 to 3 near or on the surface of the object to be measured;
Applying a varying magnetic field to the object to be measured by an electromagnetic ultrasonic sensor;
Receiving the longitudinal wave ultrasonic wave oscillating in the thickness direction of the object to be measured and the transverse wave ultrasonic wave oscillating in the direction parallel to the surface of the object to be measured at one measurement place by the varying magnetic field;
Adjusting the frequency of the variable magnetic field so that the longitudinal wave ultrasonic wave causes resonance; adjusting the frequency of the variable magnetic field so that the transverse wave ultrasonic wave causes resonance; and
Detecting the resonance frequency of each of the longitudinal wave ultrasound and the transverse wave ultrasound;
Calculating a resonance characteristic index of the object to be measured based on the detected resonance frequency of the longitudinal wave ultrasonic wave and the detected resonance frequency of the transverse wave ultrasonic wave;
And a step of determining a degree of embrittlement corresponding to the calculated resonance characteristic index of the measured object based on a correlation between a preset resonance characteristic index and the degree of embrittlement.

The embrittlement evaluation method according to claim 5, wherein the electromagnetic ultrasonic sensor is arranged near or on the surface of the object to be measured so that the rolling direction of the object to be measured and the width direction of the linear portion are parallel to each other.