JPS58154649A - Method and apparatus for measuring various abnormal forms in metallic deformation - Google Patents

Abstract

PURPOSE:To obtain a method and an apparatus for measuring various abnormal forms in metallic deformation which can easily measure abnormal phenomena generated just after the application of deformation working similar to hot working to a test chip to be measured, by optically measuring the deformation due to the expansion/contraction of the test chip to be measured. CONSTITUTION:Although the test chip 1' to be measured is contracted at its diameter by the change (cooling e.g.) of temperature, the contraction coefficient is changed or the test chip 1' is expanded at the generation of an abnormal form. An optical displacement meter 8 measures said change of the diameter as the change of light flux by irradiating beam light (light flux) 7 from an optical source 6 so as to be the tangent of the external circumference of the test chip 1'. The optical displacement meter 8 records the change of the diameter D of the test chip 1' as an expansion/contraction curve, so that the abnormal point can be measured. In order to measure fine displacement, the optical displacement meter 8 is provided with a high speed shifting means to make the movement of the center axis for measurement in the Z and X axial directions follow to a deformation working program.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is a method for measuring the transformation of metal under deformation, which optically measures the expansion and contraction of the metal after deforming the metal by induction heating and mechanical pressure processing. METHODS AND APPARATUS.

Generally, in order to determine the heat treatment conditions for metals such as steel materials, continuous cooling transformation diagrams (C, (', T diagrams), isothermal transformation diagrams (T diagrams),
, T, T diagram) etc. are determined by 1-meter measurements, but these are mostly measured in a static state with the specimen shape in its original shape, heated and cooled in an electric furnace or induction heating, and the expansion and contraction curves are measured. A method was adopted to find the metamorphosis point by
% Publication No. 48-43837).

However, in the actual manufacturing process of steel materials, even if the continuous casting method or the smoking ingot method is used, the heated steel ingot undergoes deformation processing by going through a process such as rolling by some O method. These hot workings result in a temperature drop of over 1M after processing.
It has a strong influence on the transformation phenomenon that occurs during cooling (cooling), and is measured in a conventional static, non-deformed state.
The measurement results may vary considerably depending on the strain rate [) and the amount of processing (strain). 114 of rolled steel by combining recent hot working l1 conditions and various alloy designs.
As the technology for improving 11 properties has progressed, measurements of O-density m after hot working have become increasingly important.

In the conventional static heat #gt measurement method, minute changes in the length of the test specimen were directly linked to the differential transformer to measure expansion contraction 11i1 of the specimen directly from the test specimen. Apply the same deformation and processing to the specimen to be measured, and automatically transform it after 90 minutes.
III. Making decisions is subject to various constraints. In other words, in deformation processing @WC, after removing the processing tool from the specimen, the contact hand of the differential transformer must be placed on the deformed specimen, but the specimen must be cooled to a specified level after deformation. In some cases, refrigerant gas is sprayed to prevent this, and in other cases, heating is performed. In this way, it is difficult to provide initial working conditions such as removing the additive, cooling or heating the specimen, and at the same time measure the expansion and contraction of the specimen at the same timing. This was done in consideration of the circumstances, and by optically determining the expansion/contraction (displacement due to #j) of the specimen to be measured, it was possible to detect the transformation phenomenon immediately after applying deformation processing similar to hot working to the specimen to be measured. It is an object of the present invention to provide a method and apparatus for measuring various deformities under deformation of metals, which can easily measure 11.

Embodiments of the present invention will be described in detail below with reference to the drawings.

That is, FIG. 1 is a schematic diagram of a deformation processing and heating/cooling apparatus according to the present invention. Reference numeral 1 denotes a specimen to be measured made of metal, which is usually formed into a substantially cylindrical shape with a diameter of 10 mm and a height of about 12 to 15 inches. A processing jig 2.3 of a pressurizing mechanism is provided above and below the specimen 1 to be measured, and a spinning heating coil 5 with a cooling nozzle 4♀ inside is provided around the specimen 1 to be measured. . The specimen 1 to be measured is heated by applying current to the induction heating coil 5, and the specimen 1 to be measured is cooled by changing the current applied to the induction heating coil 50 or by spraying from the cooling nozzle 4. Furthermore, the deformation of the specimen 1 to be measured is carried out at a predetermined temperature using a pressurizing mechanism via processing jigs 2 and 3.

FIG. 2 shows temperature changes during transformation measurement under deformation of the specimen 1 to be measured. First, the specimen 1 to be measured is heated to around 1100°C and held at that temperature for a certain period of time, and then the specimen 1 to be measured is controlled to a deformation processing target temperature of 900°C, and this processing temperature A
At this time, a predetermined processing amount (strain) is applied at a predetermined processing speed, and as shown in FIG. 3, the piece is deformed into a substantially disk shape, resulting in nine measured seat pieces 1'. In that situation, the sample to be measured 1'
Transformation measurement begins at the same time as the cooling process begins.

That is, as shown in FIG. 4, the diameter of the specimen 1' to be measured shrinks due to a change in temperature (in this case cooling) 41C, but if transformation occurs, the shrinkage rate changes or the diameter changes in the direction of expansion. Change. Such a change in diameter can be achieved by irradiating a beam of light (light flux) 7 from a light source 6 so as to be tangential to the outer periphery of the specimen I', and detecting the change in the light flux using, for example, an image dissector tube. It can be measured by measuring with an optical displacement meter 8 corresponding to the light receiver. This change in the diameter of the specimen 1' to be measured is recorded as an expansion/contraction curve by the optical displacement meter 8, making it possible to measure the transformation point. Therefore, in order to measure minute displacements, the optical displacement meter 8 needs to narrow down its measurement field to 200 μm8 FIIL.

Due to such a narrow field of view, as shown in Fig. 5, if the measurement center point (Tag, T) of the specimen 1 to be measured before deformation is at point a, after processing deformation, the measurement center point ( target) moves to 0 point. Therefore, the optical displacement meter 8 is provided with a high-speed movement mechanism that allows the two-axis movement of the measurement center axis and the X-axis movement to follow the deformed grout 4.

Next, to describe the moving mechanism of the optical displacement meter 8, as shown in FIG. are set to match. The central optical axis of the optical displacement meter 8 is at the position drawn on the drawing. On the other hand, after the pressure processing, the center of the outer circumferential surface of the deformed specimen 1' to be measured moves to point C.

In this case, if we disassemble point C, the center of the outer peripheral surface of the specimen 1' to be measured after deformation, point a moves to point Hby on the vertical axis (two axes), and point Vibx on the horizontal axis (X axis). to move to. Therefore, although there are some differences depending on the material of the specimen to be measured, temperature, etc., point A moves to point C along a trajectory like a dotted line.

In this case, since the amount of machining (strain) in the two-axis directions of the specimen to be measured is determined in advance, a preset grogram signal PS is added to the two-axis signal circuit 9 during deformation processing, and the two-axis step The ping motor 10 is rotated, the camera z and the X-axis moving mechanism 11 are driven, and the optical displacement meter 8 is moved in the direction of the arrow y. At the same time, a signal that follows the displacement in the X direction of the outer circumferential surface of the deformed specimen 1' to be measured is obtained from the X-axis stem tracking circuit 12, and this signal is applied to the Then, the camera z and the X-axis moving mechanism 11 are driven to move the optical displacement meter 8 in the direction of the arrow X. In this way, the optical displacement meter 8 stops when its central optical axis coincides with point C of the sample to be measured 1', and starts measuring the transformation at this position. That is, when a volume change occurs in the deformed specimen 1' to be measured due to transformation, this appears as a change (expansion or contraction) in the diameter of the specimen 1' to be measured, which can be measured as the displacement at point C.

Next, to describe the operation of the X-axis stalk tracking circuit 12, as shown in FIG. 1
32 and is set to be distributed left and right centering on the vertical border.

In this case, the signal output of the X-axis stem following circuit 12 is at zero level. When the specimen 1 to be measured is deformed in this state, the
] Since the center of the outer circumferential surface of the fixed specimen 1' moves from point a to point C in the direction of the dotted line arrow, a signal is generated in the output of the X-axis stalk tracking circuit 12 in the positive or negative direction. This signal output rotates the X-axis circumferential steering wheel and the ping motor 13, drives the camera z and the X-axis movement mechanism 11, and moves the optical displacement meter 8 so that the optical axis center is in the direction of the zero point. Then, at a position where the optical axis center of the optical displacement meter 8 coincides with point C, the output of the X-axis stem follower circuit 12 becomes zero, and the optical displacement meter 8 stops. When the optical displacement meter 8 stops, all circuits related to the moving mechanism stop, the optical displacement meter 8 is fixed, and the C of the specimen 1' to be measured is
Measure minute displacements of points within a fixed field of view.

By performing induction heating on the temperature side of the specimen to be measured in this manner, continuous temperature control by a program is facilitated, and deformation of the specimen to be measured at a predetermined temperature is facilitated. In addition, by optically measuring the changes caused by expansion and contraction of the #1 specimen, it is possible to easily measure the transformation phenomenon immediately after the specimen is subjected to a deformation process similar to hot working. can. In particular, by narrowing down the measurement field of view of the camera section of the optical displacement meter to about 200 microns, minute displacements of the specimen to be measured can be accurately measured. in this case,
By moving the camera section of the optical displacement meter simultaneously with the deformation of the specimen to be measured so that the center of the optical axis of the camera section of the optical displacement meter coincides with the center of the outer peripheral surface of the specimen to be measured, It is possible to accurately measure minute displacements of the specimen to be measured.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram showing an example of a heating/cooling device and a pressurizing mechanism according to the present invention, FIG. 2 is a diagram showing an example of temperature program characteristics according to the present invention, and FIG. 3 is a diagram showing an example of a temperature program characteristic according to the present invention. FIG. 4 is a side view showing an example of the state of the measurement specimen after deformation; FIG. 4 is a schematic configuration diagram showing an example of the optical measuring section according to the present invention; FIG.
The figure is a configuration explanatory diagram showing an example of the moving part of the optical displacement meter according to the present invention, and FIG. 6 is a rounded diagram illustrating an example of the relationship between the specimen to be measured and the field of view of the camera unit according to the present invention. . 1.1'...Measurement specimen made of metal, 2,3...
No. circuit, 10... 2-axis steering umbrella ping motor, 11.
...Camera Z, X-axis movement mechanism, 12...X-axis stalk tracking circuit.

Claims (2)

[Claims] (1) A test specimen made of metal is induction heated or cooled according to a predetermined program, the test specimen at a predetermined temperature is deformed by pressure processing, and a light source is applied to the outer peripheral surface of the illumination test specimen. The optical displacement needle follows the displacement of the outer peripheral surface of the specimen to be measured so that the optical axis of the optical displacement needle coincides with one point on the outer peripheral surface of the specimen to be measured that is irradiated with this light. A method for measuring various transformations of metal under deformation, characterized by moving the optical axis of a displacement meter and determining expansion and contraction t-111 of a specimen to be measured from changes in the optical axis of the optical displacement meter. (2) A device that heats or cools a test piece made of metal according to a predetermined temperature and durham, and a device that pressurizes and deforms the test piece that has been brought to a predetermined temperature by this device; A light source that irradiates the outer peripheral surface of the specimen to be measured with light, and a moving mechanism that aligns the center of the optical axis with one point on the outer peripheral surface of the specimen to be measured that is irradiated with light by the light source. an optical displacement meter, and detects the movement of the optical axis of the optical displacement meter.