There is rarely a direct relationship between salt spray resistance and corrosion resistance in other media. Because various factors affect the corrosion process, such as the formation of the protective film varies greatly with the conditions. Therefore, the results obtained by the test cannot be used as a direct guide for the corrosion resistance of the test cover in the environment in which it is used. Similarly, the performance of different coatings in the test cannot directly guide the relative corrosion resistance of these coatings. 1. Scope of application This International Standard specifies the equipment, reagents and methods used in the copper accelerated acetate spray test for evaluating the quality of metal coatings prepared in accordance with the coating or product specifications. This test is designed to evaluate the quality of decorative Cu + Ni + Cr or Ni + Cr coatings, and is also applicable to the anodized aluminum layer. Unless otherwise specified, this test is only applicable to the above coating. This test is unreliable for comparing Cu + Ni + Cr or Ni + Cr coatings, because the acceleration of copper corrosion products of Cu + Ni + Cr coating is masked by the effect of copper ions present in the test solution. This International Standard does not specify the type of test piece, the exposure period of a specific product, or the interpretation of the results. These details are provided by the appropriate overlay or product specifications. 2. Test solution 2.1 The test solution is prepared by dissolving sodium chloride in distilled water or deionized water so that the concentration is 50 ± 5g / L. Sodium chloride must be white and dissolved in water to obtain a colorless solution. In principle, sodium chloride cannot contain copper and nickel, and the amount of sodium iodide should be less than 0.1%, and the total impurities calculated based on dry salt should not exceed 0.4%. If the pH of the configured solution is outside the range of 6.0 to 7.0, check for harmful impurities in both salt and water. 2.2 A sufficient amount of copper dichloride (CuCI2? 2H20) needs to be added to the salt solution so that its concentration is 0.26 ± 0.02g / L (equal to (0.205 ± 0.05g / L CuCI2? 2H20) 2.3 It needs to be added in the salt solution Sufficient amount of glacial acetic acid to ensure that the pH of the salt spray solution sample collected in the test chamber is between 3.1 and 3.3. If the pH value of the initially prepared solution is 3.0 to 3.1, the pH value of the spray solution will probably be in this range. All pH values ​​should be measured with an electric measuring instrument at 25 ° C. However, the precision pH test paper that can read the 0.3pH increase and decrease and is verified by electric measurement can be used for daily inspection. Analytical grade glacial acetic acid can be added Or sodium hydroxide to make any necessary adjustments. 2.4 In order to remove any material that clogs the spray equipment nozzles, the solution must be filtered before being filled into the equipment storage tank. 3. Equipment 3.1 The equipment includes the following components 3.1.1 Spray box, use anti-spray Manufacture or lining of materials corroded by solution. The volume of the tank is not less than 0.2m3, preferably not less than 0.4m3, because the volume is too small to ensure uniform distribution of spray. The droplets on the surface will not fall on the test piece. The shape and size should be such that the amount of solution collected in the tank is within the range indicated in Section 6.2. 3.1.2 Heat supply and control methods, the heat eye can maintain the parts in the tank to the specified temperature (see 6.1). The temperature is determined by the placement Control the thermostat at least 100mm away from the wall of the box in the box or placed in the water jacket. In either case, the thermometer should be placed at least 10mm away from the wall of the box and can be read from outside the box. Salt solution spraying method, including a clean air source with controlled pressure and humidity. A water storage tank for spray solution and one or more sprayers made of spray solution corrosive materials. The compressed air supplied to the sprayer must pass through the filter to To remove all oil traces or solid impurities, the pressure should be 70 ~ 170KPa. In order to prevent the vaporization of water from the spray droplets, the air should pass through a saturated tower filled with water, whose temperature is several degrees higher than the humidity of the box before entering the sprayer Humidify the air. The appropriate temperature depends on the pressure used and the type of nozzle, and is adjusted to maintain the spray collection speed and concentration in the box. Within the enclosure (see 6.2). The tank containing the spray solution is a bucket made of materials resistant to saline solution and must be equipped with a device to maintain a certain liquid level in the tank. The sprayer should be made of inert materials, such as glass or plastic. The baffle prevents direct impact of salt spray. The use of an adjustable baffle helps to uniformly distribute the spray throughout the tank. 3.1.4 There are at least two suitable collectors. The collector is a funnel with glass or other chemically inert materials. The neck is inserted into a measuring cylinder or other container with a funnel diameter of 100 mm and a collection area of ​​approximately 80 cm2. The collector is placed in the box where the sample is placed. One is near the nozzle inlet and the other is away from the nozzle inlet. The location where they are placed requires collection It's just salt mist, not liquid dripping from the sample or other parts of the tank. 3.2 If the equipment has been tested for salt spray or has been tested for a solution other than that specified in this test, it must be fully cleaned before use. 4. Test pieces 4.1 The type and number of test pieces, their shape and size should be selected according to the test coating or product specifications. When there is no such specification, the details about the sample shall be mutually agreed by the relevant parties. 4.2 The test piece must be fully cleaned before the test. The cleaning method used depends on the surface condition and the nature of the dirt. Do not use any abrasives or solvents that will attack the surface of the specimen. After cleaning the sample, care must be taken not to be contaminated by excessive or careless touch. 4.3 If the specimen is cut from a larger plated workpiece, the coating in the additional area of ​​the cut must not be damaged. Unless otherwise specified, the cut edges must be adequately protected by covering. These coatings are a suitable material that is stable under test conditions, such as paint, paraffin, or adhesive tape. 5. Exposure method of the sample 5.1 The sample cannot be placed on the direct process of the mist particles coming out of the nozzle in the box. A baffle can be used to prevent the spray solution from directly impacting the sample. 5.2 The angle at which the specimen is exposed and placed in the box is important. In principle, the surface should be flat, with the test face facing up and as far as possible at an angle of 20o to the vertical. In all cases, this angle should be within 15o to 30o. In the case of irregular surfaces, for example, the entire workpiece should be made as close to these regulations as possible. 5.3 The test pieces should be arranged in such a way that the samples do not touch each other or the box. At the same time, the test surface is exposed to the natural circulation of the spray. The sample can be placed on different horizontal surfaces in the box, as long as the solution does not fall from the upper sample or the bracket to the lower sample. 5.4 The sample holder must be made of inert non-metallic materials, such as glass, plastic or appropriately coated wood. If the sample needs to be hung, the hanger material cannot be metal, and must use rayon, cotton fiber or other inert insulating materials. 6. Operating conditions 6.1 The temperature in the spray box is 50 ± 2 ℃, and the fluctuation should be as small as possible throughout the test period. 6.2 The concentration of the solution collected in each collector should be 50 ± 10g / L (see 3.1.4), and the pH value should be in the range of 3.1 to 3.3 (see 2.3). The average speed of the solution collected by each collector, measured after at least 24h, should be 1 ~ 2mL / h for every 80cm2. 6.3 The sprayed solution is no longer used. Note: In order to compare the test conditions in different laboratories or on different dates, a nickel plate can be used for calibration. The size of the nickel plate is 100X75mm2. The weight loss of the sample exposed to each of the four corners in the box for 24 hours should be 3 ~ 70mg. Samples are processed as described in Appendix A. 7. Test period 7.1 The test period shall be determined according to the test cover or product specifications. When there is no provision, the test period shall be mutually agreed by the relevant parties. The recommended test time is: 2, 4, 16, 24, 48, 96, 240, 480, 720h. 7.2 The spraying shall not be interrupted within the specified test period. Only when a short-term on-site visual test sample is needed and the salt water in the water storage tank in the tank must be replenished but cannot be replenished from outside the tank, the salt spray tank can be opened. 7.3 If the end point of the test depends on the appearance of the initial corrosion spot, the specimen should be checked frequently. For this reason, these samples should not be tested together with other samples with a predetermined sample period. 7.4 For a predetermined period of testing, the inspection can be arranged according to the period, but the sample surface cannot be damaged during the test, and the unpacking time required to check and record any observable changes should be as short as possible. 8. After the cleaning test of the sample after the test, remove the sample from the box. In order to reduce the risk of removing corrosion products, the samples are dried for 0.5 ~ 1h before cleaning. Carefully remove the residue of the spray solution from the surface of the sample. The appropriate method is to gently wash or soak the test piece in flowing water with a temperature not exceeding 40 ° C, and then immediately place the sample in compressed air (air flow of about 300mm) at a pressure not exceeding 200KPa to dry it. 9. Evaluation of results In order to meet different test purposes, many different test result evaluation standards can be used. For example: changes in quality, changes observed with a microscope, or mechanical properties. Usually the appropriate standard is proposed by the test cover or product specification. The general records of most tests only need to consider the following aspects: 1) appearance after the test; 2) appearance after removing the corrosion products; 3) corrosion defects Distribution and quantity, namely pitting corrosion, cracks, bubbles, etc. These can be easily evaluated according to the method specified in ISO-1462 (Metal Covering-Non-Anode Coating of Bottom Metal-Accelerated Corrosion Process-Evaluation Method of Results). 4) The time before corrosion begins to appear. 10. Test report 10.1 The test report must indicate the results obtained in accordance with the specified results evaluation criteria. If necessary, the average results obtained for each sample and each group of parallel samples shall be indicated. If necessary, a photograph of the sample must be attached. 10.2 The test report must include information on the test method. This information may vary according to the purpose of the test and the instructions specified for it. However, the general detailed items are roughly as follows: 1) Description of the product to be tested; 2) The shape and size of the sample, the area and nature of the sample surface; 3) Preparation of the sample, including cleaning treatment and test before the test Protection of sample corners or other special parts; 4) Description of known characteristics of coating and surface treatment; 5) Number of samples provided for testing for each coating or product; 6) Cleaning method used for samples after testing , And explain the weightlessness caused by cleaning when appropriate; 7) the angle of inclination of the surface when the sample; 8) the test temperature; 9) the test period; 10) in order to check the accuracy of the working conditions, specially placed in the test box The nature of any test board and the results obtained. Appendix A Calibration of test conditions A.1 General This appendix describes the method of evaluating the corrosion effect under the conditions given in the spray box. The results obtained can be carried out with different laboratories or test conditions obtained in the same laboratory at different times. Compare. A.2 Test sample The sample should be cut from a commercial pure nickel plate containing Ni not less than 99.%, C≤0.15%, S≤0.01%, Fe≤0.4% and Cu≤0.25%. The thickness of the plate is about 1mm, and the sample size is 100X75mm2. When the sample is used for the first time, it should be cleaned according to the general method specified in 4.2, and then a 1: 4 (volume ratio) hydrochloric acid solution with a temperature of 21 ~ 24 ° C Immerse for 2 minutes, rinse in hot flowing water, dry in an oven at 105 ° C, cool and weigh at room temperature, and the sample can be reused during the test. The method of removing the corrosion products at the end of the test hopes to obtain a good surface so that it can be reused in subsequent tests. A.3 Placement of test specimens The weighed test specimens should be placed vertically in the test chamber at an inclination angle of 30 ° C from the vertical, and the upward surface should face the direction of spray incidence. The bracket should be made of or coated with an inert material such as plastic. The top edge of the sample should be at the same level as the top of the spray collector. A.4 Determination of weightlessness 24 hours after the test, the sample is rinsed with cold water to remove residual salt mist, and then immersed in a 1: 4 (volume ratio) hydrochloric acid solution at a temperature of 21 to 24 ° C for 2 minutes to remove corrosion products. The pliers of the sample must be covered with nickel or Monel alloy or the part contacting the sample with an inert material, then each sample is rinsed in water, dried in an oven at 150 ℃, cooled to room temperature and weighed
1. Dressing Table style
Everyone has their own different aesthetic vision, so in terms of appearance, as long as you like it, but the appearance of the dressing table is best to be painted with paint, so that it is easy to clean, and the cosmetics will not penetrate into the dressing table and affect the dressing. appearance of the desk. At the same time, you can also choose the style of the dresser according to the overall style of the room.
When choosing the mirror of the dressing table, you can`t just look at it and think it is fine. The mirror of the dressing table must be a folded design, so that when you look in the mirror, you can see all angles of your face and clearly see it. Where is your makeup problem?
3. Check the quality of the Dressing Table
Dressing tables are mostly made of man-made sheets. The owner should check the quality certificate when selecting them, and look at the formaldehyde content and quality description of the sheets. It is best to get close to the dressing table and smell it to see if there is a pungent smell. If there is, it is best Do not buy.
The size of the dressing table is preferably 400*1000 (40 cm wide and 100 cm long), so that it is easy to place cosmetics. If the size of the dressing table is too small, it will be more troublesome if the cosmetics cannot be placed. The height of the dressing table is generally between 70-75 cm, which is more suitable for owners of ordinary height.
5. the matching chair for the Dressing Table
When choosing a dresser, you must ask clearly to see if there are matching chairs. It is best to choose a dresser with matching chairs, so as not to be uncoordinated in general and cause trouble to your dressing.
It can be divided into two types: independent and combined. The independent style is to set up the dressing table separately, which is more flexible and casual, and the decorative effect is often more prominent. The combined type is to combine the dressing table with other furniture, which is suitable for small families with limited space.
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