JPH0215026B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a standard test piece in which a simulated defect is artificially created, which is used in a non-destructive testing method to confirm the reliability of the test method.

Conventionally, simulated defect standard test pieces have been widely used in non-destructive testing methods, including ultrasonic flaw detection, to improve their accuracy and reliability.

However, in most cases, a standard hole is formed from the outer surface of the specimen by machining, etc., and standard defects include those that have an exposed structure that is spatially connected to the outside, or that the standard hole is prevented from oxidizing. The entrance to the hole is plugged with a suitable material in order to

However, most of the actual defects are buried inside, such as cavities in castings, cracks in welds, and blowholes, and the simulated defects are similar in shape and structure to these actual defects. It cannot be said that they are necessarily compatible.

This is a problem that cannot be overlooked in non-destructive testing methods such as ultrasonic flaw detection.

In particular, the reflection behavior of ultrasonic waves is different between an internally buried defect and a cavity connected to the outer surface, so when examining the performance of a probe for detecting actual buried defects, it is difficult to detect different types of defects. This means that you are looking for flaws. Therefore, it is desirable to create an artificial defect that corresponds directly to the actual defect in terms of shape and structure, or is similar to the actual defect. It was impossible to install it at any arbitrary position inside.

The present invention has been made in view of the above-mentioned problems, and the structure thereof will be explained below based on the accompanying drawings. FIG. 1 shows a conventional standard test piece 2 in which a standard hole (artificial defect) 1 is exposed on the lower surface of the test piece. Here, figure a is a side view and figure b is a bottom view. On the other hand, FIG. 2 shows a standard test piece provided by the present invention, and as shown in FIG.
A standard hole (artificial defect) 1 is made in one of the specimens 3', and then solid state welding is performed using pressure presses 5 and 5' as shown in figure b, and the final result is shown in figure c. A small hollow artificial defect 1 appears to be embedded inside. To explain this in more detail with reference to FIG. 3, first, as shown in FIG.
The method is to make it separately into 3' parts and combine them as shown in Figure b.

Before assembly, a hole is made in advance on the upper surface at a distance A from the front end of the lower handle with a plate thickness H. Next, when this is metallurgically joined and integrated using the solid phase joining method, A from the front as shown in Figure b.
A standard specimen b having a small hollow artificial defect 1 at a distance H from the lower surface can be produced.

In this case, if a diffusion welding method is adopted as the solid-phase joining method, the joined portion will not only not reflect ultrasonic waves but also be able to be completely joined and integrated metallurgically. Furthermore, since the deformation of the joint due to the welding operation is very small, the geometrical shape in the vicinity can be precisely controlled. Furthermore, there are no material limitations, it is possible to join different materials, and it is also possible to precisely create artificial defects that exist at the joining interface of different materials. Furthermore, if the artificial defect is filled with a foreign material such as ceramic in advance, it is possible to create an artificial defect related to an inclusion.

Various methods can be used to create holes, that is, to create artificial defects, depending on the shape and size of the hole, but chemical methods such as photo etching can be used to create holes in their depth, The size can be processed down to the μm order.

Furthermore, by appropriately selecting the number of divided test pieces before joining and integrating, the thickness of each test piece, the position and size of standard holes (artificial defects), and their shape and number, single or multiple Make the cavity any size,
It can be made into any shape. For example, a test piece having an arbitrary defect shape can be manufactured by inserting an insert material having a predetermined defect shape into the joint before joining together.

FIG. 4 is a reproduction of a microscopic photograph of a cross section of a test piece in which artificial defect cavities are provided in a mild steel block as an example of the present invention, manufactured by diffusion welding. Previous) The joint interface 7 was initially located horizontally along the lower edge of the artificial defect, but has now become completely integrated.

[Brief explanation of drawings]

Figure 1 shows a conventional standard test piece for non-destructive testing, in which figure a is a side view, figure b is a bottom view, and figure 2 is a
Figures a, b, and c are side views of a test piece for explaining the manufacturing procedure of the present invention, Figures 3 a and b are perspective views, and Figure 4
The figure is a copy of a longitudinal cross-section of a test piece obtained according to the present invention, including a surface of an artificial defect, in place of a microscopic photograph. 1...Standard hole (artificial defect), 2...Standard test piece,
3, 3'...Divided test piece, 4...Joint interface, 5,
5'...Pressure press (for solid phase welding), 6
...Standard test piece (made after joining and integration), 7...
...original joint position.

Claims (1)

[Claims] 1 A small cavity is provided on one or more surfaces of the joint surfaces of two or more divided test pieces made of the same or different materials, or a substance different from the constituent material of the divided test piece is embedded in the cavity. A method for manufacturing a simulated defect standard test piece for non-destructive testing, characterized in that the divided test pieces are then joined and integrated by a solid-phase joining method.