Salt Spray Resistance Test Standard for Electroplating
Author: Robby
The standard of electroplating salt spray resistance test mainly includes neutral salt spray test, acidic salt spray test, copper ion accelerated salt spray test and so on.
Neutral Salt Spray Test (NSS) is the most common salt spray test method, using 5% sodium chloride saline solution, the pH value of the solution is controlled between 6.5 and 7.2, and the test temperature is generally 35°C. The test steps include equipment inspection, preparation of salt solution, cleaning of the test samples, setting up of the test conditions, fixing of the samples and angular adjustments, starting of the test, and post-test treatment. The test procedure includes equipment inspection, preparation of salt solution, cleaning of test specimen, setting of test conditions, specimen fixation and angle adjustment, start of test and post-test processing.
Acid Salt Spray Test (ASS) is based on the neutral salt spray test, adding a certain amount of acetic acid to reduce the pH value of the solution to 3.0 to 3.1 in order to accelerate the corrosion rate, and is suitable for comparing the corrosion resistance of different materials or coatings. The operation procedure is similar to that of NSS, but it is necessary to pay attention to the preparation of the solution and the adjustment of pH value.
Copper Ion Accelerated Salt Spray Test (CASS) is based on the Acetate Spray Test with the addition of copper chloride to accelerate the corrosion process. This method is suitable for evaluating the corrosion resistance of plating layers.
Judgment methods for salt spray test results include the grading judgment method, the weighing judgment method, the corrosive appearance judgment method, and the corrosion data information statistical analysis method. Grading judgment method is based on the ratio of corrosion area to total area for rating; weighing judgment method is to assess the degree of corrosion by comparing the weight change of the sample before and after the test; corrosion emergence judgment method is to observe whether there are corrosion products; corrosion data information statistical analysis is to assess the corrosion situation through data analysis.