JP6655369B2 - Water-based dye penetrant for penetrant testing - Google Patents

Description

  The present invention relates to a water-based dyeing penetrant used in a penetrating inspection test for detecting fine opening defects existing on the surface of various metal members such as electronic devices and automobiles, and particularly to penetration of a magnesium alloy which is susceptible to corrosion. The present invention relates to a water-based dyeing penetrant that can be suitably used for a flaw detection test.

  Magnesium alloys are lightweight, strong, easy to process, and have electromagnetic wave shielding properties, and thus can be suitably used for various components such as electronic devices such as mobile phones and computers and automobiles. In addition, since it is possible to recycle, various members using a magnesium alloy are increasing year by year.

  Generally, a penetrant inspection test is applied to detection of an opening defect such as a fine crack or a pinhole on the surface of various members using a magnesium alloy.

  As is well known, the penetrant inspection is a type of nondestructive inspection method and is standardized in "JIS Z 2343-1 to 6". The basic aspect of the method is that, usually, a highly permeable dyeing and permeating solution in which a dye is dissolved is adhered to the surface of the inspection object to penetrate the opening defect portion, and then the surface of the inspection object surface does not penetrate into the defect portion. Then, the excess dye permeate remaining on the surface of the test object is removed, and then a thin inorganic white powder such as a magnesium carbonate powder or a calcium carbonate powder (called “developer” by those skilled in the art) is applied to the surface of the inspection object. Forming a layer, and causing the dye penetrating liquid penetrating into the opening defect portion by the thin layer to be drawn out to the surface of the thin layer to reveal a defect indicating pattern, under natural light or white light, or a digital camera, etc. Is observed, and the existence and position of the opening defect portion are detected based on the defect indication pattern.

Since the magnesium contained in the magnesium alloy is a base metal, it is very susceptible to corrosion in the air or in the presence of water, and if a dyeing penetrant in which the solvent is water is used (hereinafter referred to as “water-based dyeing penetrant”), The magnesium alloy is corroded.
Therefore, it is difficult for a water-based dyeing penetrant to meet the requirements for metal corrosion rate specified in JIS Z 2343-2 (ISO3452-2). A dye penetrant, which is a solvent (hereinafter referred to as "solvent-based dye penetrant"), is used.

However, since the solvent-based dyeing infiltration liquid is flammable, there is a risk of fire, and the handling and storage amounts are strictly regulated by the Fire Service Law.
In addition, since it contains VOCs (volatile organic solvents), it has a negative impact on the human body and the environment, is subject to regulations under the Organic Solvent Poisoning Prevention Law, and sellers and purchasers need to pay attention to handling .

With a water-based dyeing permeate, there is no danger of fire, so there is no restriction on the amount handled or stored, and there is no adverse effect on the human body or the environment.
Therefore, development of a water-based dyeing infiltration solution that is water-based and can be used for a flaw detection test of a magnesium alloy is desired.

JP 2008-169416 A

  Patent Document 1 discloses that a rust inhibitor obtained by mixing a succinamic acid-based compound and a basic compound in water can prevent corrosion of a magnesium alloy.

  However, the dye is not sufficiently dissolved in the rust preventive described in Patent Document 1, and since the magnesium alloy is corroded by the remaining dye, it cannot be used as a dye penetrant for flaw detection of the magnesium alloy. There's a problem.

  The present inventors have set a technical problem to solve the above-mentioned problems, and as a result of repeating many trial-and-error trial productions and experiments, have found that pentadecenyl succinic anhydride, a solvent having a glycol skeleton, and a water-soluble dye. With a water-based dyeing and permeating solution containing, the magnesium alloy does not corrode and becomes a water-based dyeing and permeating solution that meets the requirements specified in JIS Z 2343-2 (ISO3452-2). The technical problem has been achieved by obtaining remarkable knowledge that there is no restriction on the handling amount or storage amount, and that the dyeing permeate has no adverse effect on the human body or the environment.

  The technical problem can be solved by the present invention as follows.

The present invention, pentadecenyl 0.05 to 1.0 wt% of succinic anhydride and hexylene glycol, ethylene glycol, diethylene glycol, 10 to 50 wt% of one or more solvents selected from propylene glycol and water-soluble dye fees 0. The solvent containing the 5 to 3% by weight Ru penetrant water-based dye penetrant der water.

Further, the present invention is Ru penetrant methods der to detect the opening defect of the metal with the water-based dye penetrant.

Further, the present invention, the metal is Ru said penetrant methods der magnesium alloy.

  ADVANTAGE OF THE INVENTION According to this invention, since a fine opening defect part of a metal can be detected with high sensitivity, and corrosion of a magnesium alloy can be suppressed, even if it is used for a flaw detection test of a magnesium alloy, JIS Z 2343-2 (ISO3452- A water-based dyeing penetrant for penetrant testing that meets the requirements specified in 2) can be provided.

  Further, since the dye infiltration solution according to the present invention is water-based, there is no danger of fire, there is no restriction on the amount of handling and storage, and there is no adverse effect on the human body and environment of the handlers and the like. .

  When the water-based dyeing permeate according to the present invention is used, an opening defect having a depth of about 30 to 50 μm can be detected.

6 is a photograph of a test piece immersion surface of Examples 1 to 6. 9 is a photograph of a test piece immersion surface of Comparative Examples 1 to 14. It is a photograph which shows the result of the sensitivity test of an Example and a comparative example.

The present invention is a water-based dyeing permeate containing pentadecenyl succinic anhydride, a solvent having a glycol skeleton, and a water-soluble dye and using water as a solvent.
In this specification, a solvent having a glycol skeleton may be referred to as a “glycol-based solvent”.

  The content of pentadecenyl succinic anhydride is preferably 0.05 to 1.0% by weight, more preferably 0.05 to 0.7% by weight. If the content is less than 0.05% by weight, the corrosion of the magnesium alloy cannot be sufficiently suppressed. Therefore, the requirements specified in JIS Z 2343-2 (ISO3452-2) are not satisfied. In this case, the excess dye permeate does not sufficiently drop, and a clear defect indicating pattern cannot be obtained.

Incidentally, alkenyl succinic acids such as pentadecenyl succinic anhydride is the making thin oxide film with respect to the magnesium alloys.
The present inventors presume that the water-based dyeing and permeating solution of the present invention suppresses the corrosion of a magnesium alloy by an oxide film formed by pentadecenyl succinic anhydride.

  The water-based dye permeate according to the present invention contains one or more glycol solvents.

  The content of the glycol solvent is preferably from 10 to 50% by weight. If the amount of the glycol solvent is less than 10% by weight, the pentadecenyl succinic anhydride and the water-soluble dye are not sufficiently dissolved in water as a solvent, and if the amount is more than 50% by weight, the corrosion inhibiting effect of the magnesium alloy is impaired. Because you do.

  Examples of the glycol solvent that can be used in the present invention include hexylene glycol, ethylene glycol, diethylene glycol, and propylene glycol.

  The water-soluble dye is not particularly limited as long as it does not inhibit the corrosion inhibiting effect of the magnesium alloy, but ROB-B (solvent Red 49, manufactured by Orient Chemical Industries, Ltd.) is preferred.

The content of the water-soluble dye is preferably 0.5 to 3% by weight, more preferably 1.0 to 2.0% by weight.
If the content is less than 0.5% by weight, a clear defect indication pattern cannot be obtained, and if the content exceeds 3% by weight, an increase in flaw detection accuracy cannot be expected, and the corrosion inhibiting effect of the magnesium alloy may be impaired. It is.

  As the solvent, any of pure water, distilled water and tap water can be used.

1 shows an embodiment of a penetrant testing method using a water-based dyeing penetrant according to the present invention.
In a test operation atmosphere at room temperature (approximately 20 ° C.), the water-based dyeing and permeating solution according to the present invention stored at the same room temperature is applied to the surface of the test object and allowed to adhere to penetrate the opening defect (penetration treatment). .
Next, the surface of the inspection object is cleaned with tap water or a cleaning agent such as Ecocheck (registered trademark) ER-ST (manufactured by Marktec Co., Ltd.), and the water pressure is about 0.3 to 0.5 MPa and the flow rate is 1 to 3 L / min. The excess dye permeate remaining on the surface of the test object without permeating into the defect is washed and removed (cleaning process).
After the specimen is dried, the surface is coated with an inorganic white powder such as a magnesium carbonate powder or a calcium carbonate powder, or a developer such as Super Check (registered trademark) UD-ST (manufactured by Marktec Co., Ltd.), and the defect is removed. The opening defect portion of the inspection object is detected by visually observing a defect indicating pattern that appears due to the dye penetration liquid remaining in the developer penetrating into the developer, or by photographing with a digital camera or the like.

  The present invention will be described in more detail with reference to examples and comparative examples.

(Corrosion test)
Water-based dyeing of one side of magnesium alloy AZ31B (magnesium alloy plate containing 3% by weight of aluminum and 1% by weight of zinc: length 10cm, width 1.2cm, thickness 0.05cm) as described in Tables 1-5 The test piece was immersed in a permeating solution, allowed to stand at 50 ° C. for 2 hours, and then washed with acetone. The corrosion of the surface immersed in the water-based dyeing infiltration solution (hereinafter referred to as “immersion surface”) was visually observed. No change was indicated by ○, light brown color was changed by Δ, black or white changed by X. evaluated.

(Sensitivity test)
The sensitivity test was performed using a type 2 contrasting test piece specified in JIS Z2343-3.
After infiltrating the test piece with the water-based dyeing permeate blended as described in Tables 1 to 5 for 5 minutes, the excess dyeing permeate was removed with tap water, and dried at 60 ° C for 5 minutes, then Super Check UD-ST The star-shaped design pattern (defect-designed pattern) that appeared after the application of the film was photographed with a digital camera and visually observed. If all five star-shaped design patterns could be detected, 、 and 4 were detected. Was evaluated as "Poor", and those having less than 4 dyes or those in which the water-soluble dye did not dissolve and the defective portion could not be detected were evaluated as x.

PDSA-DA described in each table is pentadecenyl succinic anhydride, DSA is dodecenyl succinic anhydride, OSA is octenyl succinic anhydride, ODSA is tetrapropenyl succinic anhydride, BDG is 2- (2-butoxy (Ethoxy) ethanol.
ROB-B is a water-soluble red dye, and Fast Red 260 (manufactured by Futaba Chemical Laboratory) is a dispersible red dye.
The amount of each component in each table is% by weight.

  From Tables 1 to 5, from pentadecenyl succinic anhydride and a solvent having a glycol skeleton and a water-soluble dye, if it is a water-based dyeing penetrant using water as a solvent, the corrosion of the magnesium alloy is suppressed, and magnesium with high sensitivity is obtained. It was proved that the alloy could be detected.

  The water-based dyeing and permeating solution according to the present invention can detect flaws with high sensitivity even with a magnesium alloy which is susceptible to corrosion, and has no flash point, so there is no restriction on the amount handled or stored according to the Fire Service Law, and it contains VOCs. Therefore, the present invention has great industrial applicability because it has no adverse effect on the handlers and the environment.

Claims (3)

Pentadecenyl 0.05-1.0 wt% succinic anhydride with hexylene glycol, ethylene glycol, diethylene glycol, 10 to 50 wt% of one or more solvents selected from propylene glycol and water-soluble dye fees 0. 5 to 3% by weight, and the solvent is water. Penetrant test method for detecting an opening defect of the metal with water-based dye penetrant according to claim 1 Symbol placement. The penetrant testing method according to claim 2 , wherein the metal is a magnesium alloy.