5 Factors of Rusty Stainless Steel Filter

- May 17, 2018-

  Stainless steel filters also rust during use. To understand its causes, we must first understand what is going on with rust. Which, in the end why the stainless steel filter will rust it, in everyone's impression of the "stainless steel" is not rust! Today we explain you in five ways:

  1. The nature of rust is actually an oxidation reaction. Iron is an extremely chemically active element, but iron itself does not react with water. Only when the oxygen in the air is dissolved in water, the iron is oxidized by the oxygen in the water to generate iron oxide. The brown-red rust on the iron surface is iron oxide. Spongy iron oxide can easily absorb water in the air, which further exacerbates the iron rust process.

  2. The stainless steel filter's resistance to rust is determined by the material composition, structure, and surface condition of the stainless steel material. The most critical factor is the chemical composition of stainless steel. Chromium and nickel contained in the stainless steel composition are the decisive factors in improving the corrosion resistance of the stainless steel.

 3. Chromium is a chemically stable element with high corrosion resistance. In air, oxidation is slow even under red hot conditions. In oxidatively corrupted and non-corrosive media, chromium can also rapidly generate a dense passivation film on the steel surface to prevent the metal matrix from being damaged. Experiments have shown that when the chromium content in the steel matrix reaches 12.5% or more, A fairly stable passivation film will form on the surface, and a catastrophic sudden change occurs in the rust resistance of the steel, which is why the amount of nickel in the stainless steel must reach 12% or more.

  4. Nickel is also a “respector” of the rust resistance of stainless steel, but simply relying on nickel to make the substrate significantly change the corrosion resistance, the amount of nickel to reach 27%. Therefore, nickel alone cannot constitute stainless steel. However, nickel and chromium exist in stainless steel at the same time, it will greatly enhance the stainless steel's ability to resist rust.

  5. In addition to the above factors, the purity of the stainless steel, the uniformity of the matrix elements, and the ratio of manganese, nitrogen, and carbon are all factors that affect the stainless steel's ability to resist corrosion.