JPS58205838A - Measurement of void for metal material - Google Patents

Abstract

PURPOSE:To measure the vacancy rate of metal material by photoelectric inspection of the intensity of spectral lines only peculiar to metal utilizing emission spectroscope. CONSTITUTION:For example, discharge light emission of a low voltage spark is caused between a sample and pair electrodes by electric excitation with a light emitter. Then, the light emitted is analyzed into spectral lines for metal elements with a diffraction grating of a spectrometer and only the spectral lines of internal standard elements underlying the sample is introduced to a photomultiplier tube in a photoelectric photometer from those obtained to charge an integrater of the photometry section with an output current of the photomultiplier tube proportional to the intensity of the spectral lines as electric charge and the value thereof is indicated on a recorder or the like with an A/D converter or the like for instance. In this manner, metal sample to be inspected undergoes discharge emission, spectroscope and photoelectric photometry on the same condition as the standard sample and the dose detected is compared to measure the vacancy rate.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for measuring the porosity of a metal material by extracting only the spectral lines peculiar to metals using emission spectroscopy and photoelectrically measuring the intensity thereof. be.

Conventionally, the porosity of metal materials has been measured by testing samples taken from the metal material whose porosity is to be measured, in accordance with the "M microscopic test method for steel glue [metallic inclusions]" stipulated in J.E.S. GO555. After polishing the surface and inserting a Galanu plate with 20 vertical and horizontal grid lines into the eyepiece of a microscope with a standard magnification of 400 times, the surface to be inspected was randomly inspected several dozen times. The measurement method used was to count the number of lattice point centers occupied by , and calculate the ratio to the total number of lattice points within the field of view to determine the porosity.

However, the measurement method described above requires a long time for measurement, and the measurement results vary depending on the experience and proficiency of the measurer, resulting in very poor measurement accuracy and work efficiency.

The purpose of the present invention is to eliminate the drawbacks of the conventional method.The present invention aims to eliminate the drawbacks of the conventional method. Spectrometer spectrometer spectrometer, from the spectrum line of the n
Only the spectral µ rays of the internal standard element, which is the metallic element used as the bake for Buban, are introduced into a photomultiplier tube, and the nubeku) A/ray intensity is photoelectrically measured, and the value is calculated using a method with a known porosity. This method is characterized by measuring the porosity of a metal material by comparing it with a calibration curve prepared in advance using standard samples.

The method for measuring the porosity of metal materials according to the present invention will be explained below based on Examples.

First of all, although the present invention can be applied to metal materials such as iron, steel, copper, titanium, and aluminum, the case of carbon steel will be described as one example.

The apparatus for carrying out the present invention can be roughly divided into a light emitting device, a spectroscopic device, and a photoelectric photometer. (low-voltage spark) discharge and emit light.

Next, the emitted light is divided into various metal elements such as Fe, lfi, Or, Mn, and Cu using a diffraction grating of a spectrometer.
, MO1■, At, T'i, etc., and only the spectral lines of the metal element that is the base of the sample, that is, the internal standard element, are analyzed by photoelectrons in a photogravimetric photometer. The output current of the photomultiplier tube, which is proportional to the intensity of the Nuvector line, is charged as a charge (voltage) to the integrator (integration unit) of the photometry section, and the value is transferred to an analog/digital converter, for example. It is recorded or instructed by a recorder, indicator, etc.

By the way, the amount of charge varies depending on the porosity of the metal material, and as the porosity increases, the amount of charge decreases. If the amount of charge is determined as follows and a relationship curve between the porosity and the amount of charge is created in advance, that is, a calibration curve, the porosity of the sample can be detected from the amount of charge measured on the metal material sample. It is possible.

Figure 1 shows an example of a calibration curve obtained from six types of standard samples of sintered bodies of Tl14600 series alloy steel powder, each with different porosity. rjFe/: 2714 people, Fea: 2874J were taken out, and the discharge was integrated for 5 seconds after preliminary discharge for 5 seconds with LVS discharge, and shows the average intensity of 3 repetitions.

The counter electrode at this time was made of tungsten with a diameter of 6fi and had a conical shape with a tip of 60°.The discharge gap between it and the standard sample was r15.5ff, and the distance was 51;/mi,n from the front of the light emitting stand. Argon gas is ejected to replace the air, avoiding the absorption of oxygen and preventing oxidation of the sample, as well as increasing the efficiency of excitation.

Therefore, by performing discharge luminescence, spectroscopy, and photoelectric photometry on a sample of a metal material whose unknown porosity is to be measured under the same conditions as the standard sample, and comparing the values with the calibration curve, the porosity can be easily determined. rate can be detected.

Note that the light emitting device, spectroscopic device, photoelectric photometer, etc.
It is possible to utilize a known device used in emission spectroscopic analysis of metal materials using photoelectric photometry.

Since the present invention is configured as described above, the porosity of a metal material can be measured quickly, easily, and accurately by comparing it with a calibration curve prepared in advance.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an example of the relationship between porosity and charge amount used in the present invention, that is, a calibration curve.

Claims (1)

[Claims] (1) Discharge light is generated between the sample of the metal material whose porosity is to be measured and the counter electrode using an electrical excitation method, and the light is separated into spectral lines by a spectrometer. Only the Nubek I-/shi line is guided to a photomultiplier tube, and an output current proportional to the spectral line intensity is charged to an integrator. Porosity measurement of a metal material, characterized in that the porosity of the metal material is detected by comparing it with a calibration curve prepared in advance based on the amount of charge (voltage) measured from a sample under the same conditions as above. Method.