For salt spray testing, we recommend our salt spray test chamber（←Click to learn more）
1.The automatic water adding system is adopted, which can automatically supplement the water level when the water level is insufficient, and the test will not be interrupted;
2.The precision glass nozzle diffuses with, falls on the test piece naturally, and ensures no crystal blockage;
3.the spray tower is equipped with a conical disperser, which has the functions of guiding fog, regulating fog quantity and even dropping fog
Salt spray corrosion test chamber is an environmental test that mainly uses artificial simulated salt spray environmental conditions created by salt spray testing equipment to evaluate the corrosion resistance of products or metal materials. Used in aerospace, aviation, ships, hardware and electronics, electrical appliances, chemicals, postal and telecommunications, automobiles and motorcycles, industrial and mining enterprises. Quality inspection and other departments and industries. It can also be used in the heat treatment and surface treatment industry. For example, QPQ process plans will require smoke experiments, so heat treatment and surface treatment will be used, and electroplating factories will also use it.
Neutral salt spray test (NSS test)
The neutral salt spray test is an artificially accelerated corrosive test. Used to test the corrosion resistance of protective coatings (such as zinc layers, cadmium layers) and protective decorative coatings (nickel-chromium coatings, etc.). It uses 5% sodium chloride aqueous solution with a pH value of 6.5~7.2. The relative humidity of the salt water is >95% under the condition of (35±2)℃, and is sprayed on the plated parts with a certain amount of fog reduction [1~2mL /h·80cm2)]The spray adopts continuous spray. 24h is a cycle.
The pH value of the experimental solution should be adjusted so that the pH value of the spray solution collected in the salt spray box is between 6.5 and 7.2. The pH value should be measured with an acidimeter at 25°C ± 2°C. Precision pH test paper with a measurement accuracy of no more than 0.3 can also be used for daily testing. When out of range, analytical grade hydrochloric acid, sodium hydroxide or sodium bicarbonate can be added for adjustment.
Loss of carbon dioxide from the solution during spraying may cause pH changes. Corresponding measures should be taken, for example, heating the solution to over 35°C before feeding it into the instrument or preparing the solution with new boiling water to reduce the carbon dioxide content in the solution and avoid changes in pH value.
Neutral salt spray test is suitable for:
——Metals and their alloys;
——Metal covering layer (anodic or cathodic);
——Conversion coating;
——Anodic oxidation film;
——Organic coating on metal substrate.
Q-fog CRH salt spray test chamber can be used to conduct neutral salt spray test, acetic salt spray test and CASS salt spray test
Q-fog CRH salt spray test chamber can be used to conduct neutral salt spray test, acetic salt spray test and CASS salt spray test
Acetic acid salt spray test (AASS test)
Add an appropriate amount of glacial acetic acid to the prepared salt solution to ensure that the pH value of the collection liquid in the salt spray box is 3.1 to 3.3. If the pH value of the initially prepared solution is 3.0 to 3.1, the pH value of the collection solution is generally in the range of 3.1 to 3.3. The pH value should be measured with an acidimeter at 25°C ± 2°C. Precision pH test paper with a measurement accuracy of no more than 0.1 can also be used for daily testing. The pH value of the solution can be adjusted with glacial acetic acid or sodium hydroxide.
The acetic acid salt spray test is suitable for copper + nickel + chromium or nickel + chromium decorative coatings, and is also suitable for aluminum anodized films.
Copper Accelerated Acetic Salt Spray Test (CASS Test)
In the prepared salt solution, add copper chloride (CuCl2·2H2O) with a concentration of 0.26 g/L±0.02 g/L (i.e. 0.205g/L±0.015 g/L anhydrous copper chloride). The pH value adjustment method of the solution is the same as 3.2.3.
The copper accelerated acetate salt spray test is suitable for copper + nickel + chromium or nickel + chromium decorative coatings, and is also suitable for aluminum anodized films.
Test methods Neutral salt spray test (NSS) Acetic salt spray test (AASS) Copper accelerated acetic acid salt spray test (CASS)
Temperature 35℃ ± 2 ℃35℃ ± 2 ℃50℃ ± 2 ℃
The average sedimentation rate of a horizontal area of 80cm2 is 1.5mL/h ±0.5mL/h
The concentration of sodium chloride solution (collection solution) is 50g/L ± 5g/L
PH value 6.5~7.23.1~3.33.1~3.3
Comparison of three test methods in the standard "GB/T 10125 Artificial Atmosphere Corrosion Test Salt Spray Test"
CASS test is the abbreviation of copper accelerated acetate test. It is used to test the corrosion resistance of copper-nickel-chromium composite coating and nickel-chromium coating. The results are more consistent with the results of atmospheric exposure experiments. It is to add 0.26g/L cuprous chloride to 5% sodium chloride aqueous solution, and use glacial acetic acid to adjust the pH value = 3.2±0.1. This acidic solution is sprayed onto the surface of the plated part. Other conditions and methods are the same as The neutral salt spray test method is the same. All reagents used were chemically pure grade reagents.
This test condition is more severe than the neutral salt spray test condition. Mainly used for testing the corrosion resistance of nickel composite coatings.