Steel ball is the processing ball made of processed steel. So the basic performance of steel also reflects the basic performance of the steel ball. Steel balls are mainly divided into stainless steel ball, bearing steel ball, alloy steel ball, carbon steel ball, tool steel ball and so on. Among them, for stainless steel ball, its biggest feature is anti-rust. In fact, from the appearance point of view, steel balls are wrapped by metal-colored coat. As for what is the real stainless steel ball, it’s not difficult to judge from its appearance. Only through physical and chemical testing can we identify the authenticity of stainless steel ball accurately.
In general, salt spray tests are one of the most commonly used test methods. What is salt spray test? Salt spray test is an environmental test, major using the artificial simulation salt spray environmental conditions created by salt spray test equipment to assess the corrosion resistance of the product or metal. Salt spray test principle is to achieve the desired purpose or results through the salt spray on the material. The atmosphere contains oxygen, humidity, temperature changes and pollutants and other corrosive ingredients. So most metal materials are relatively easy to produce chemical reactions in these conditions, causing the damage and deterioration of the metal surface. The corrosion that the salt spray acts on the surface of the metal material is caused by the electrochemical reaction of the chloride penetrating the oxide layer and the protective layer of the metal surface and internal metals.
For stainless steel ball, its material chemical elements contain nickel, which is a distinct feature of stainless steel material different from other steel. And the penetration that nickel on the oxygen and chloride ion has a certain degree of resistance. So the ball surface does not play a very strong corrosive effect. Stainless steel ball, especially stainless steel 304 / 304L and 316 / 316L, in the salt spray test, their corrosion resistance is relatively strong. And their corrosion resistance time is relatively long, generally up to 72 hours or more.
If they are steel balls of other materials, such as bearing steel balls, carbon steel balls, alloy steel ball and so on. Steel balls’ material is lack of nickel, and has high carbon content. So they are easier to produce electrochemical reaction with the oxygen, humidity, temperature and others. Steel balls begin to corrosion within a few hours.
Thus, salt spray test is an effective and accurate test method to identify the authenticity of stainless steel ball.