JPS61288360A - Analysis and display method for surface condition - Google Patents

Abstract

PURPOSE:To display the coarseness, defects and the like broadly within a viewfield of the naked eye, by detecting the surface condition of a mechanical part or the like with a scanning type electron microscope, and display two- dimensionally by separating in a specific quantity after memorizing plurally and continuously the resultant signals. CONSTITUTION:Electron beams 2a from a scanning type electron microscope are radiated over a sample 3 such as a mechanical part, and numerous analyzing points 4 are scanned two-dimensionally. Then the secondary electron beams 2b responding to the analyzing points 4 are detected by a detector 5, memorized in a computer 7 through a control unit 6, and this process is carried out on all analyzing points 4 continuously. After that, the size or the depth of each recessed and projecting point over the surface of the sample 3, obtained from the memorized values, is displayed on the display device 8, by separating in a specific quantity, in specific marks or colors two-dimensionally. Therefore, the coarseness or defects can be displayed broadly within the viewfield of the naked eye, and can be used effectively for detecting nondistructive defects and the like.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention quantitatively measures the size and depth of irregularities on the surface of a material in a microscopic field or defects opened in the surface in a macroscopic field.
This invention relates to a surface state analysis and display method that displays a dimensional wide area.

[Prior art and problems]

The properties of the surfaces of mechanical parts are largely influenced by their roughness or the presence or absence of defects.

As a conventional method for measuring and displaying the roughness of a surface, a method is known in which the roughness is measured one-dimensionally using a roughness meter and displayed in one display. However, with this method, it is difficult to measure and display in a microscopic field. Moreover, it is difficult to perform stepwise display and two-dimensional display according to the roughness.

A method is also known in which surface roughness is displayed as a secondary electron image using a scanning electron microscope to three-dimensionally observe unevenness. However, such a method is limited to a minute part in a microscopic field of view, and cannot observe a wide area of a macroscopic field of view, for example, an area larger than several squares.

Moreover, it is not possible to display the defect depth or size of one surface step by step.

The present invention is a surface condition analysis and display method that analyzes the roughness of a surface or defects with openings in the surface under a microscopic field, accumulates a large number of them in succession, and displays them over a wide area under a macroscopic view. This is what we are trying to provide.

[Means for solving problems]

The present invention provides a method for quantitatively analyzing and displaying the roughness of a surface or a defect opening in the surface as the roughness or the depth of the defect. A large number of positions and sizes of the unevenness are continuously detected two-dimensionally as image signals, the signals are stored in a storage device, and then the size or depth of the unevenness is divided into fixed amounts. It is characterized by displaying a wide area two-dimensionally with the naked eye using specific symbols or colors that correspond to each category.

[Effect]

According to the method of the present invention described above, surface roughness or defects with openings on the surface are detected in a microscopic field using a scanning electron microscope, and a large number of defects are continuously stored and accumulated in a storage device. Roughness or defects can be displayed over a wide area with a macroscopic view.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIG.

First, the electron generator 1 of the scanning electron microscope converges the smear beam 2a and irradiates it onto the surface of the sample 3. This material 3 has an area of several Lo11 squares, but there are many analysis points (approximately 100 μm square) 4 on its surface, and electron beams 2
A moves a large number of analysis points 4 two-dimensionally by moving the sample 3 in the X and Y directions by a sample drive device (not shown). However, at one analysis point 4, the electron beam 2a scans a minute area of the analysis point 4 and generates a secondary electron beam 2b. This secondary electron beam 2b is detected by a secondary electron detector 5, and information based on the secondary electron image is stored in a computer 7 via a control device 6. Next, the information stored in the computer 7 is outputted to the display device 8 by dividing the size or depth of the unevenness into a certain amount.
Displays various forms of symbols, colors, etc. in a two-dimensional, wide-area manner with the naked eye.

According to the method of the present invention, information that could not be obtained using conventional observation methods could be quantitatively obtained through the following operations.

FIG. 2 is an optical microscope observation of the metal structure of stainless steel that has suffered creep damage at high temperatures. This metal structure consists of a parent phase 11 and grain boundaries 12, and a precipitate 13 and a grain boundary precipitate 14 are observed in the parent phase 11 and grain boundaries 12, and moreover, in contact with the grain boundary precipitate 14, Micropores 15 were observed. Therefore, by the method of the present invention, only the micropores 15 in the metal structure shown in FIG. 2 were detected from the unevenness of the secondary electron image as recesses of a certain depth or more and displayed. As a result, as shown in the third factor, micropores could be displayed in the smooth surface 16 as an image 17 of a certain depth or more. This image 17 generally corresponds well to the micropores 15 observed with the optical microscope structure shown in FIG. A newly obtained image 18b was observed.

Therefore, according to the present invention, information that cannot be obtained by conventional observation methods can be quantitatively obtained.

〔Effect of the invention〕

As detailed above,5 according to the present invention, it is possible to analyze surface roughness or defects with openings in the surface with a microscopic field of view, accumulate a large number of them continuously, and display them over a wide area with a macroscopic field of view5. Surface roughness analysis of mechanical parts 1 It is possible to provide a surface condition analysis and display method that can be effectively applied to micro defect detection, non-destructive defect detection, etc. of mechanical parts.

[Brief explanation of drawings]

Fig. 1 is a schematic diagram showing an apparatus used for analyzing and displaying surface conditions in an embodiment of the present invention, Fig. 2 is an optical microscope observation of the metal structure of stainless steel that has suffered creep damage at high temperatures, and Fig. 3 The figure shows micropores in the same metal structure analyzed using the method of the present invention. 1...Electron generator, 2m...Electron beam, 2b...
・Secondary electron beam, 3...sample, 4...analysis point, 5...
・Secondary electron detector, 7...Computer% 8...Display device, 11...Material phase, 12...Grain boundary, 15.
...Minute pores. 17, 18a, 18b---image. Applicant Sub-Agent Patent Attorney Takehiko Suzue 1st vl

Claims (1)

[Claims] In a method of quantitatively analyzing and displaying surface roughness or defects opening on the surface as roughness or defect depth, microscopic irregularities on the surface are measured using a scanning electron microscope as a signal of a secondary electron image. After continuously detecting a large number of positions and sizes two-dimensionally and storing the signals in a storage device, the size or depth of the unevenness is divided into a certain amount and identified to correspond to each division. A method for analyzing and displaying surface conditions characterized by displaying a wide area two-dimensionally with the naked eye using symbols or colors.