JP3041279U - Simulated test piece for radiation damage measurement - Google Patents

Abstract

(57) 【Abstract】 PROBLEM TO BE SOLVED: A simulated test piece for radiation damage measurement, which models a void generation due to radiation damage for applying an ultrasonic flaw detection test to detect defects in nuclear structural materials. SOLUTION: A resin powder is melted, and an alumina powder for modeling a void formation is added and mixed therewith to form a thin plate, which is then crushed into small pieces, and the small pieces are remelted into a desired shape. Simulated test piece for radiation damage measurement, which was molded and processed.

Description

[Detailed description of the invention]

[0001]

[Technical field to which the invention belongs]

 The present invention relates to a simulated test piece for an ultrasonic flaw detection test for detecting defects such as voids caused by radiation damage in nuclear structural materials and the like.

In particular, the simulated test piece of the present invention relates to a simulated test piece for measuring radiation damage in which void generation due to radiation damage is modeled by using alumina powder as a substitute for defects such as voids. It is a thing.

[0003]

[Prior art]

 In structural materials that have been internally damaged by radiation irradiation, minute voids are created at the crystal boundaries of the metallic structure inside, and when these voids eventually gather and become larger voids, ultrasonic flaw detection becomes possible. In other words, the size of the void caused by radiation damage is extremely small in the initial stage, but if the voids become large by sticking together or they are dense, ultrasonic flaw detection is possible. .

By the way, heretofore, there has been no example of manufacturing a simulated test piece for measuring radiation damage, which is used for an ultrasonic flaw detection test and which models void generation simulating radiation damage.

Therefore, in order to obtain a test piece which is actually irradiated with radiation in a nuclear reactor or the like and damaged by radiation, it is necessary to irradiate the test piece with radiation for a long period of time. There has been a problem that post-irradiation tests such as mechanical strength tests (tensile test, impact test, fracture toughness test) and metallographic tests by X-ray microanalyzer, which are carried out in the hot cell after the irradiation, are not easy.

[0006]

[Issues to be solved by the invention]

 According to the present invention, it is possible to easily manufacture a test piece that can be simulated as a test piece that is actually irradiated by radiation in a nuclear reactor and damaged by radiation. The research on can be done efficiently and quantitatively.

[0007]

[Means for Solving the Problems]

 The test piece of the present invention uses alumina powder instead of voids. The presence of this alumina powder in the test piece of the present invention makes it possible to detect it by ultrasonic waves as in the case of voids.

The test piece of the present invention uses a powdered resin as a base material for embedding the alumina powder, and an alumina powder (particle size: 22 μm) as a material corresponding to the void.

The test piece of the present invention is manufactured in two steps in order to uniformly disperse the alumina powder in the resin. First, the powdered resin is heated to 450 ° C. to be fluidized, and then a predetermined amount of alumina powder is added, and this is poured into a thin plate mold and cooled. Next, this thin plate-shaped molded body is crushed into small pieces. After melting this small piece again, it is put in a mold and cooled to manufacture a test piece of a desired shape.

[0010]

[Embodiment of the invention]

 Resins used in the present invention include polyester resins that are generally commercially available.

[0011]

【Example】

 An embodiment of manufacturing the simulated test piece for measuring radiation damage according to the present invention will be specifically described with reference to FIG.

As the first step, first, the powdered resin was heated to 450 ° C. and melted. Alumina powder having a particle size of 22 μm was added to the molten resin and mixed uniformly. Molten resin obtained by uniformly mixing the obtained alumina powder was poured into a mold to obtain a colorless and transparent thin plate-shaped molded body having a thickness of about 1 mm. After the molded body was naturally cooled, it was crushed into small pieces of several mm.

As a second step, the crushed pieces obtained in the first step were heated to 450 ° C. and remelted. The remelted material was poured into a mold and naturally cooled to produce a thick plate-shaped (thickness: about 20 mm) test piece.

As a result of microscopic observation of the cross section of the manufactured test piece, it was confirmed that the alumina powder was uniformly dispersed. Also, as a result of performing an ultrasonic flaw detection test on the test piece, the ultrasonic propagation characteristics were changed by adjusting the mixing ratio (weight ratio) of the powder resin and the alumina powder in the range of about 1,000: 1. We were able to obtain a test piece that could simulate the material freely.

[0015]

[Effect of the invention]

 As a result of the ultrasonic flaw detection test of the test piece, the material whose ultrasonic wave propagation characteristics were changed by adjusting the mixing ratio (weight ratio) of the powdered resin and the alumina powder was about 1,000: 1. Since it can be manufactured freely, we were able to obtain a simulated test piece for radiation damage measurement that can detect flaws on a minute simulated test basis.

[Brief description of the drawings]

FIG. 1 is a diagram showing a process of producing a simulated test piece for measuring radiation damage according to the present invention.

FIG. 2 is a view showing a simulated test piece for measuring radiation damage according to the present invention.

[Explanation of symbols]

 1: transparent resin, 2: alumina powder

Claims (1)

[Utility model registration claims] 1. A radiation damage measurement in which a powder resin is melted, and then aluminal powder is added and mixed to form a thin plate, which is then crushed into small pieces, and the small pieces are remelted and formed into a desired shape. Simulated test piece.