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Different material stainless steel wire mesh has different acid resistance, please kindly check the 304,316 and 316L stainless steel in phosphoric acid and sulfuric acid as below:

1. The acid resistance of 304 316 and 316L stainless steel in phosphoric acid:

In general, in pure phosphoric acid without impurities, commonly used stainless steel can solve the corossion problems.

For example, in some productio process, 304(18-8, Cr-Ni) stainless steel can be used to store 85% cold phosphoric acid and treat 5% cold phosphoric acid, it is satisfying.

316 stainless steel has better corossion resistance than 304. And if the content of fluorine is not too high, 316 type stainless steel can be used to store and produce fluorine.When phosphoric acid concentration of 85%, 316 type stainless steel should be under 100℃ temperture.

Mo content in 316L stainless steel is about 2%-3%, it has better corossion resistance, and with the increasing of Mo contents, the phosphate-resistant performance become better.

But in production of wet phosphoric acid, the phosphoric acid usually contains more impurities, like: F-、Cl- 、SO42-、Fe3+、Al3+、Mg2+ etc. Among them, except Fe3+, others accelerate the corrosion of stainless steel, especially F-、Cl- more intense. In order to improve the stainless steel corossion resistance in phosphoric acid, increase the content of Cr and Mo in stainless steel will be more obvious, and Cr has most significant effect. The effect of Mo is only effective when the amount of Cr in the steel is low (for example, 20% to 21%); when Cr and Mo are high, the effect of Ni in the steel is not significant, so if possible,you may try 443 or 444 stainless steel.

2. The acid resistance of 304 316 and 316L stainless steel in sulfuric acid:

When the sulfuric acid concentration of 80% or more at room temperature, you can use 304 type stainless steel.

If sulfuric acid can be inflated, and if the temperture up to 50℃, can use the 316 type stainless steel and the concentration of 10% sulfuric acid in contact.

If in air-free solution, the corrosiveness is even greater, if temperture up to 65℃, Sulfuric acid concentration of 5%, you can use 317 stainless steel.

If there are other materials in the solution, it is possible to significantly improve the corrosion rate.

In the medium concentration of hot solution, as long as there are 500-2000PPm of copper ions, you can use 304 stainless steel.

The effect of other additives may be reversed. You can use contain Mo, Cu, Si stainless steel, such as stainless steel 316L.

In summary, the acid and corossion resistance of 304, 316, 316L stainless steel wire mesh in turn enhanced.

Any questions, please contact us freely.