CN103389316A

CN103389316A - Silicon steel texture measuring method

Info

Publication number: CN103389316A
Application number: CN2013103057401A
Authority: CN
Inventors: 王志奋; 陈士华; 吴立新; 韩荣东; 张萍; 关云; 邓照军; 周顺兵; 张彦文; 许竹桃
Original assignee: Wuhan Iron and Steel Group Corp
Current assignee: Wuhan Iron and Steel Co Ltd
Priority date: 2013-07-19
Filing date: 2013-07-19
Publication date: 2013-11-13
Anticipated expiration: 2033-07-19
Also published as: CN103389316B

Abstract

The invention discloses a silicon steel texture measuring method. The silicon steel texture measuring method comprises the following steps of preparing an EBSD analysis sample, measuring orientation distribution diagrams of half-thickness areas at three or more different positions of a longitudinal section of the sample by EBSD equipment, dividing a measured area into at least 10 equal-area zones from the steel plate surface to the plate thickness center, carrying out analysis to obtain ODF diagrams of the different positions, calculating density fractions f (hkl) of all crystal faces {hkl}, calculating an average value of the density fractions f (hkl) of the crystal faces {hkl} which are in different positions and have the same thickness, and drawing a data diagram of the silicon steel texture along a plate thickness direction. Through measurement of the ODF diagrams and quantitative calculation of the density fractions f (hkl) of the crystal faces {hkl}, the problem of high difficulty of XRD quantitative analysis is solved. Through measurement of data of multiple zones, the error caused by a too small EBSD measuring zone is eliminated and data is more accurate.

Description

Silicon steel texture measurement method

Technical field

The present invention relates to the measuring method of silicon steel, refer to particularly a kind of silicon steel texture measurement method.

Background technology

Orientation silicon steel is the important soft magnetic material that is widely used in electric power, electronics industry.If obtained preferred orientation, the arrangement of individual crystal grain makes it＜001〉axle almost with steel plate, rolls to parallel, can reduce the iron loss of orientation silicon steel, improve magnetoconductivity, increase the magnetic circuit of direction of easy axis, make material be more suitable for the applications such as generating and substation transformer, therefore improving texture is the effective way that reduces iron loss and improve magnetoconductivity.

Research silicon steel is to control the key of silicon steel production technology, the performance of final decision silicon steel in the texture of the steel plate of the different operations such as hot rolling, normalizing, decarburizing annealing.The outstanding feature of orientation silicon steel is to start just to exist texture difference (claiming the texture gradient) from hot rolling technology from the sample surfaces to the center.Therefore, the distribution situation of Texture thickness of slab direction is an important indicator of research steel plate texture.The crystal grain of rolled plate is the effect of under tension and pressure simultaneously, therefore often with some crystallographic direction＜uvw〉parallel roll to, also { hkl} is parallel to the face of rolling, and forms plate texture with some crystal face simultaneously.Plate texture commonly used hkl}＜uvw〉expression.

Usually measure along the texture variation main process of steel plate thickness direction as follows: adopt the methods such as mechanical lapping, line cutting or chemical corrosion to carry out attenuate to steel plate, after being thinned to specific thickness, measure the texture of surface of steel plate with X-ray diffractometer.After measuring the texture of different-thickness, can draw the texture situation of change along the thickness of slab direction.But there are following problems in this method:

1, sample preparation is difficult, obtain the sample of different-thickness position, needs use different thining methods, and the shortcoming of main method for making sample is as follows: the mechanical lapping time is longer, and abrasive surface is difficult to remain a plane; Chemical corrosion is difficult to control etching time and thickness; The line cutting needs to use special cutting equipment;

2, sense cycle is long, repeatedly carry out because measuring process needs sample attenuate → X-ray measurement, so the cycle is longer;

3, can only survey the texture of limited several typical thickness position,, as thickness of slab 1/4He center etc., increase the thickness position of measuring as need, can obviously extend Measuring Time.

Therefore,, with the texture of traditional X-ray measurement along the steel plate thickness direction, there are the problems such as sample preparation is difficult, the cycle is long, measurement point is few, measuring error is larger.

In addition, traditional texture measurement method such as X-ray diffraction (XRD) can only be measured the texture of macroscopic view, can't measure the orientation relationship of microcell or each crystal grain.And measuring ODF figure with XRD, to carry out quantitative error calculated larger.The another kind of method of measuring the method for texture adopts EBSD, be Electron Back-Scattered Diffraction (electron backscatter diffraction), can measure the grain orientation distribution plan of microcell, but have measurement range less, problem that error is larger.

Summary of the invention

Purpose of the present invention will overcome the existing deficiency of prior art exactly, and a kind of silicon steel texture measurement method of having used EBSD is provided, and has overcome simultaneously this problem that commercial measurement scope is little, error is larger.

For achieving the above object, silicon steel texture measurement method of the present invention, step is as follows:

A) get the silicon steel plate sample and be prepared into the EBSD analytical sample;

The distribution of orientations figure of the EBSD device measuring sample longitudinal section that B) is equipped with scanning electron microscope, thickness range, from surface of steel plate to the thickness of slab center, is measured the distribution of orientations figure in half thickness of slab zone of at least 3 different-thickness positions;

C) measure after completing and use analysis software, measured zone is divided at least 10 homalographic zones along surface of steel plate to thickness of slab center, the ODF that obtains successively by analysis from surface the diverse location zone at thickness of slab center schemes (orientation distribution function);

D) by obtaining the ODF figure in diverse location zone, by analysis software calculate each hkl}＜uvw〉texture intensity, and each crystal face hkl} intensity for should under the hkl} crystal face all hkl}＜uvw〉the intensity sum, calculate { the density mark f (hkl) of hkl} crystal face, i.e. f (hkl)=a certain { intensity of hkl} crystal face/all { intensity sums of hkl} crystal face by following formula;

E) to the distribution of orientations map analysis repeating step C in half thickness of slab zone of other thickness positions) and D), to zones of different stack pile position { the density mark f (hkl) of hkl} crystal face averages;

F) according to surface of steel plate to thickness of slab center zones of different { density mark f (hkl) mean value of hkl} crystal face, use mapping software, obtains the data plot that Texture thickness of slab direction distributes.

The present invention has overcome the defect of conventional X-ray measurement, has improved reliability and the precision analyzed, is a kind of relatively convenient and accurately measure along the texture method of steel plate thickness direction, has the following advantages:

1) sample preparation is relatively convenient, after conventional metallographic specimen preparation method, then removes the electropolishing of stress, can complete the EBSD sample preparation;

2) measurement is convenient and quick, and utilization EBSD equipment can be easy to the measurement to the cross section distribution of orientations figure from surface of steel plate to the thickness of slab center;

3) be to measure ODF figure for each zone, inverse pole figure is more accurate than measuring, and, can accurately calculate in ODF figure each hkl}＜uvw〉intensity of texture, thereby calculate each crystal face { density mark of hkl}.And, measure ODF figure with EBSD and carry out quantitatively easily calculating.

Reliable results of the present invention is accurate, and the texture of measurement can reflect the distribution situation from surface of steel plate to the thickness of slab center continuously,, by measuring the data in a plurality of zones, eliminates the EBSD measured zone too small and cause the impact of error, makes data more accurate.

Description of drawings

Fig. 1 is the distribution of orientations figure of hot rolled silicon steel plates surface to the thickness of slab center.

Fig. 2 is the distribution of orientations figure in homalographic zone.

Fig. 3 is the ODF figure in Fig. 2 homalographic zone.

Fig. 4 is the change curve of Texture thickness of slab direction.

Embodiment

The present invention is described in further detail below in conjunction with the drawings and specific embodiments.

In the following embodiment of the present invention, the analysis software that uses is INCA Crystal, is the powerful EBSD data acquisition and analysis software of several functions that the Oxford instrument provides.

Embodiment

Take hot rolled silicon steel plates as example, introduce the texture method of measuring along the thickness of slab direction, concrete steps are as follows:

A) longitudinal section along hot rolled silicon steel plates is prepared into the EBSD analytical sample by following step: (corase grind and the fine grinding) → mechanical buffing of taking a sample → inlay → polishing, and use finally electropolishing to remove stress;

The distribution of orientations figure of the EBSD device measuring sample longitudinal section that B) is equipped with scanning electron microscope, thickness range is from surface of steel plate to the thickness of slab center, and the distribution of orientations at hot rolled silicon steel plates surface to thickness of slab center is as shown in Figure 1; For guarantee to measure accurately, reduce and measure the too small and error that causes of area, measure the distribution of orientations figure in half thickness of slab zone of 3 different-thickness positions;

C) use analysis software after measurement is completed, measured zone is divided into 10 homalographic zones along surface of steel plate to thickness of slab center, obtain successively by analysis from surface the ODF figure in the diverse location zone at thickness of slab center, as shown in Figure 2, the ODF of one of them homalographic regional analysis result schemes as shown in Figure 3 the distribution of orientations in one of them homalographic zone;

D) by obtaining the ODF figure in diverse location zone, with analysis software calculate each hkl}＜uvw〉texture intensity, and each crystal face hkl} intensity for should under the hkl} crystal face all hkl}＜uvw〉the intensity sum; Calculate { the density mark f (hkl) of hkl} crystal face, i.e. f (hkl)=a certain { intensity of hkl} crystal face/all { intensity sums of hkl} crystal face by following formula; Finally obtain as η texture (111} //ND), α texture (＜110〉//RD), γ texture (＜001〉//the density mark of Main Texture such as RD);

E) the analysis repeating step C of the distribution of orientations figure in another two and half thickness of slab zones) and D), finally to zones of different stack pile position { the density mark f (hkl) of hkl} crystal face averages;

F) according to surface of steel plate to thickness of slab center zones of different { mean value of the density mark f (hkl) of hkl} crystal face, use mapping software, obtains the data plot that Texture thickness of slab direction distributes, and the texture of Texture thickness of slab direction changes as shown in Figure 4.

Claims

1. a silicon steel texture measurement method, is characterized in that, the step of the method is as follows:

C) measure after completing and use analysis software, measured zone is divided at least 10 homalographic zones along surface of steel plate to thickness of slab center, the ODF that obtains successively by analysis from surface the diverse location zone at thickness of slab center schemes;

D) by obtaining the ODF figure in diverse location zone, by analysis software calculate each hkl}＜uvw〉texture intensity, calculate { the density mark f (hkl) of hkl} crystal face, i.e. f (hkl)=a certain { intensity of hkl} crystal face/all { intensity sums of hkl} crystal face by following formula;