JP2013145136A - Fatigue testing method and fatigue testing device of test piece - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fatigue testing method and a fatigue testing device of a test piece capable of accurately determining durability, a product life cycle or the like by integrally and practically evaluating influence by a high temperature environment and a liquid medicine on a test piece.SOLUTION: A test piece 1 with which a liquid medicine absorber 2 impregnating a liquid medicine R is brought into contact is exposed to a high temperature environment, and fatigue strength of the test piece 1 is tested.

Description

  The present invention relates to a test piece fatigue test method and a fatigue test apparatus.

  Conventionally, a test for evaluating the fatigue strength of a test piece made of metal, resin, or the like has been performed.

  For example, Patent Document 1 proposes evaluating fatigue strength accompanying corrosion by repeatedly applying a stress while injecting a chemical solution (corrosive water) into a test piece. Patent Document 1 also describes that a chemical solution (corrosive water) is heated and injected at a use temperature in an actual machine.

Japanese Patent Laid-Open No. 62-153730

  Patent Document 1 mentions heating a chemical solution (corrosive water), but does not at all discuss exposing a test piece to a high temperature environment. Actually, there are members and products that are used in a high temperature environment and in the presence of a chemical solution. However, including Cited Document 1, there are currently known fatigue test methods for specimens that take these conditions into consideration. Not.

  For example, in a high temperature environment, the test piece itself is at a high temperature, which may directly affect the fatigue strength, and may also affect the temperature, corrosive action, volatility, etc. of the chemical solution. Therefore, by separating the fatigue test in the high temperature environment and the fatigue test in the presence of the chemical solution, the effect of the chemical solution on the fatigue strength of the test piece in the high temperature environment is evaluated in a combined and practical manner. It is difficult to accurately determine durability, product life, etc.

  The present invention has been made in view of the circumstances as described above, and evaluates the influence of a high temperature environment and a chemical solution on the fatigue strength of a test piece in a complex and practical manner, and accurately determines durability and the like. It is an object of the present invention to provide a fatigue test method and a fatigue test apparatus for a test piece that can be used.

  In order to solve the above problems, the fatigue test method for a test piece according to the present invention is to test the fatigue strength of the test piece by exposing the test piece in contact with the chemical solution impregnated with the chemical solution to a high temperature environment. It is characterized by that.

  In the test piece fatigue test method, it is preferable that the chemical solution is continuously supplied to the chemical solution absorber by the chemical solution supply means.

  In this test piece fatigue test method, it is more preferable that the chemical solution absorber is surrounded by a chemical solution-impermeable film.

  In this test piece fatigue test method, it is more preferable that a chemical solution storage section having the film as an outer peripheral wall is formed above the chemical solution absorber, and storing the chemical solution in the chemical solution storage section.

  The test piece fatigue test apparatus of the present invention is a test piece fatigue test apparatus having a chemical solution absorber and a chemical solution impervious film, and the periphery of the chemical solution absorber in contact with the test piece is the film. It is characterized by being surrounded.

  In this test piece fatigue testing apparatus, it is preferable that a chemical solution storage portion having the film as an outer peripheral wall is formed above the chemical solution absorber.

  According to the fatigue test method and fatigue test apparatus of the test piece of the present invention, the influence of the high temperature environment and the chemical solution on the test piece can be evaluated in a complex and practical manner, and the durability, product life, etc. can be accurately judged. it can.

It is the schematic diagram which illustrated one Embodiment of the fatigue test method of the test piece of this invention. FIG. 2 is a longitudinal sectional perspective view illustrating an outline of a main part of a fatigue test apparatus in the fatigue test method illustrated in FIG. 1.

  FIG. 1 is a schematic view illustrating one embodiment of a fatigue test method for a test piece of the present invention. FIG. 2 is a longitudinal sectional perspective view illustrating an outline of a main part of the fatigue test apparatus in the fatigue test method illustrated in FIG. 1.

  The test piece fatigue test method of the present invention is to test the fatigue strength of the test piece 1 by exposing the test piece 1 in contact with the chemical absorbent 2 impregnated with the chemical solution R to a high temperature environment. Specifically, as illustrated in FIGS. 1 and 2, the test can be performed using a fatigue test apparatus W for a test piece 1 having a chemical solution absorber 2 and a chemical solution impermeable film 3. In the fatigue test apparatus W, the periphery of the chemical solution absorber 2 in contact with the test piece 1 is surrounded by a film 3 that is impermeable to the chemical solution.

  Examples of the material of the test piece 1 include various metals and resins whose fatigue strength should be evaluated. Moreover, the test piece 1 can use what was suitably processed into the magnitude | size and shape suitable for a fatigue test. Furthermore, as a standard of the test piece 1, for example, JIS Z 2201 (metal material tensile test piece) can be considered.

  The environment to which the test piece 1 is exposed can be appropriately set assuming a high-temperature environment in which the material used as the test piece 1 is actually used, and is not particularly limited. Specifically, the temperature around the test piece 1 (atmosphere) can be appropriately set within a range of about 40 ° C. to 100 ° C., for example. Heat is transferred to the test piece 1 by setting the ambient temperature of the test piece 1 to a predetermined temperature, and the entire test piece 1 including the contact area with the chemical solution absorber 2 is heated to approximately the same as the set temperature. Be warmed. In addition, conditions such as humidity and atmospheric pressure can be set as appropriate.

  As the test method, a known test method capable of measuring and evaluating the desired strength of the test piece 1 can be appropriately employed. Specifically, for example, a tensile test, a compression test, a bending test, a shear test, an impact test and the like can be exemplified as a test method for applying repeated stress. Furthermore, in the case of a tensile test, for example, JIS Z 2241 (metal material tensile test method) can be considered.

  The chemical R is a liquid for evaluating the influence on the test piece 1 and can be appropriately selected in consideration of the environment in which the material used as the test piece 1 is actually used. Specifically, for example, the chemical solution R is prepared by adding ammonium ions, chlorine ions, sulfide ions, or the like as corrosive components to water or an organic solvent, or in which fine particles are dispersed, or a surfactant. The thing etc. can be illustrated. Further, the chemical solution R may be water that does not contain corrosive components. Furthermore, the concentration and supply amount of the chemical solution R can be set as appropriate, and are not specifically limited.

  The chemical absorber 2 is in contact with the test piece 1 and covers the entire circumference of a partial region from the outside. It is preferable that the chemical | medical solution absorber 2 is a material which can absorb the chemical | medical solution R and can maintain a moist state, and can specifically illustrate nonwoven fabrics, such as a textile fabric and felt, for example. By attaching the chemical solution absorber 2 impregnated with the chemical solution R to the test piece 1, the test piece 1 and the chemical solution R can always be in contact with each other during the test. Can be reliably evaluated.

  The upper periphery of the chemical liquid absorber 2 is disposed in close contact with the chemical liquid-impermeable film 3 over the entire circumference, and the chemical liquid R impregnated in the chemical liquid absorber 2 is prevented from leaking out to the surroundings. Has been. Further, the upper end of the film 3 is positioned above the chemical liquid absorber 2, and a chemical liquid storage portion M having the film 3 as an outer peripheral wall is formed inside the film 3. Examples of the material of the film 3 include film-like resins such as polyethylene terephthalate (PET), polyethylene (PE), and polyvinyl chloride (PVC). In a high temperature environment, there is a concern that the chemical solution R evaporates from the chemical solution absorber 2, but the periphery of the chemical solution absorber 2 is surrounded by the film 3, so that the chemical solution R from the chemical solution absorber 2 is surrounded. Evaporation can be suppressed. For this reason, the fatigue strength of the test piece 1 with respect to the chemical | medical solution R can be evaluated more correctly and efficiently. Furthermore, by storing the chemical solution R in the chemical solution storage part M formed inward of the film 3, the shortage of the chemical solution R during the test is suppressed. Further, even if the chemical solution R is excessively supplied, the chemical solution R stays in the chemical solution storage part M, so that it is difficult for the test to be adversely affected by dripping. For this reason, the state which the chemical | medical solution R and the test piece 1 contacted can be stably maintained by the chemical | medical solution storage part M formed with the film 3, and a more exact fatigue test is attained.

  The supply of the chemical solution R to the chemical solution absorber 2 is preferably performed continuously. For the supply of the chemical solution R to the chemical solution absorber 2, the supply means S for the chemical solution R can be used. The supply means S of the chemical solution R can be exemplified by one having a pump P and a tube T, for example. In this case, for example, as illustrated in FIGS. 1 and 2, the tip of the tube T connected to the pump P can be disposed so as to be positioned in the chemical solution storage unit M. Accordingly, an appropriate amount of the chemical solution R sucked by the pump P is sent out through the tube T, the chemical solution R is supplied to and stored in the chemical solution storage unit M, and the chemical solution absorber 2 is impregnated with the chemical solution R. A stable fatigue test can be performed in a state where the chemical solution R and the test piece 1 are in reliable contact with each other.

  In the fatigue test method for a test piece according to the present invention, the test piece 1 in contact with the chemical solution absorber 2 impregnated with the chemical solution R is exposed to a high temperature environment to test the fatigue strength of the test piece 1. For this reason, the state of the test piece 1 reflects a state such as breakage or corrosion due to an environmental load (high temperature environment and in the presence of the chemical solution R) where an actual member / product is expected to be exposed. Therefore, the fatigue strength of the test piece 1 in a high-temperature environment and in the presence of the chemical solution R can be evaluated in a complex and practical manner, so that durability, product life, etc. can be accurately determined based on the evaluation results. Can do.

  The fatigue test method and fatigue test apparatus for a test piece of the present invention are not limited to the above-described embodiments. For example, in FIG. 1 and FIG. 2, the form in which long plate-shaped test pieces are arranged in the vertical direction is illustrated, but the present invention is not limited to such an arrangement. The arrangement of the chemical absorber and the film can be appropriately designed in consideration of the type, shape, test method, efficiency, etc. of the test piece material.

  Hereinafter, the test piece fatigue test method and fatigue test apparatus of the present invention will be described in detail with reference to examples, but the test piece fatigue test method and fatigue test apparatus of the present invention are limited to the following examples. It is not a thing.

<Example>
In the examples, a tensile test was performed with the same configuration as that illustrated in FIG. Specifically, a test piece made of a cured acrylic resin was used as a test piece, and the periphery of the test piece made of the cured acrylic resin was covered with wool felt (chemical solution absorber). Furthermore, the periphery of the felt (chemical solution absorber) was surrounded by a film made of PET that is impermeable to chemical solution, and a chemical solution storage portion having the film as an outer peripheral wall was formed above the felt (chemical solution absorber). Then, an alcohol-based surfactant is used as a chemical solution, and an alcohol-based surfactant is supplied from above the chemical solution storage section using a pump and a tube as a supply means, and the felt (chemical solution absorber) is alcohol-based. Impregnated with surfactant.

  The tensile test is performed by holding the upper and lower ends of a test piece made of a cured acrylic resin with a gripping device and then repeatedly applying a stress of 5 Hz and 20 Mpa under an environment (atmosphere) of 50 ° C. until the fracture. The number of times was measured. In addition, during the test, about 1 drop of alcohol-based surfactant is intermittently dropped into the chemical solution reservoir for 1 to 2 minutes, and the test piece made of the cured acrylic resin and the alcohol-based surfactant are stable. To come into contact.

  As a result of the tensile test, the number of breaks was 1 to 12,000.

<Comparative example>
In the comparative example, the number of times until the test piece made of the cured acrylic resin was broken was measured under the same conditions as in the example except that no chemical solution was used.

  As a result of the tensile test, the number of breaks was 120,000 to 180,000 times.

  In the examples, a complex stress load was reproduced in a high-temperature environment and in the presence of a chemical solution, and the number of times until breakage was about 1/10 of the comparative example. On the other hand, in the method of the comparative example in which no chemical solution was used, the number of breaks was as high as 120,000 to 180,000. At first glance, it may be mistaken for having sufficient durability (product life). . According to the fatigue test method of the test piece of the present invention, it was confirmed that the influence of the high temperature environment and the chemical solution on the test piece can be evaluated in a complex and practical manner, and durability, product life, etc. can be judged accurately.

DESCRIPTION OF SYMBOLS 1 Test piece 2 Chemical solution absorber 3 Film M Chemical solution storage part R Chemical solution S Supply means W Fatigue test apparatus

Claims (6)

  A test method for fatigue of a test piece, characterized in that a test piece contacted with a chemical absorbent impregnated with a chemical solution is exposed to a high temperature environment to test the fatigue strength of the test piece.   The fatigue test method for a test piece according to claim 1, wherein the chemical solution is continuously supplied to the chemical solution absorber by a chemical solution supply means.   The fatigue test method for a test piece according to claim 1 or 2, wherein the periphery of the chemical solution absorber is surrounded by a film that is impermeable to the chemical solution.   4. The method for fatigue testing a test piece according to claim 3, wherein a chemical solution storage portion having the film as an outer peripheral wall is formed above the chemical solution absorber, and the chemical solution is stored in the chemical solution storage portion. .   A test piece fatigue test apparatus comprising a chemical absorbent and a chemical impervious film, wherein the chemical absorbent in contact with the test specimen is surrounded by the film. Fatigue testing equipment.   6. The fatigue test apparatus for a test piece according to claim 5, wherein a chemical solution storage portion having the film as an outer peripheral wall is formed above the chemical solution absorber.

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