Stainless Steel Won’t Rust?
You have probably heard that stainless steel is the most durable and long-lasting option when choosing materials. But more concretely, stainless steel is an alloy of iron that is resistant to rusting and corrosion. It contains at least 11% chromium and may contain elements such as carbon, other nonmetals, and metals to obtain other desired properties. Stainless steel's resistance to corrosion results from the chromium, which forms a passive film that can protect the material and self-heal in the presence of oxygen.
You have probably heard that stainless steel is the most durable and long-lasting option when choosing materials. But more concretely, stainless steel is an alloy of iron that is resistant to rusting and corrosion. It contains at least 11% chromium and may contain elements such as carbon, other nonmetals, and metals to obtain other desired properties. Stainless steel's resistance to corrosion results from the chromium, which forms a passive film that can protect the material and self-heal in the presence of oxygen. As with most metals (stainless steel, aluminum, nickel, and manganese) exposed to the outdoor elements, there is also the concern for rusting and corrosion over time. Although stainless steel is a superior metal due to corrosion resistance, it is not maintenance-free. It is stainless – not stainproof – meaning it must be properly and regularly cleaned to prevent rust and corrosion. The rust can form when this layer is damaged from exposure to cleaners, chloride, high humidity, high salinity environments, and/or mechanical abrasions.
How to avoid stainless steel from rusting?
We understand why stainless steel rusts, but how could we avoid stainless steel from rusting? Let's take a look at our stainless steel cable tray as an example. For stainless steel cable tray, you need to take the following conditions into account.
1.Stainless steel cable trays should be isolated from other metals and kept clean during storage and transportation, which helps to prevent pollution from dust, splotch, etc. It is prohibited to drag for avoiding possible collisions and scratches.
2.It is necessary to clean the surface of stainless steel regularly to remove surface attachments (metal particles, etc.) to reduce the external affect that may cause rust.
3. Remember to select different types of stainless steel according to the different environment, for seaside projects and ship projects, 316L stainless steel that could resist seawater corrosion would be an ideal option.
4. Try to choose reputable manufacturers as much as possible. The chemical composition of some stainless steels on the market cannot meet the corresponding national standards and material requirements, which will easily cause rust.
5. Normally, stainless steel should not be touched or welded with dissimilar metals. Because metals can have wildly different properties, fusing the wrong dissimilar metals together can cause corrosion or flimsy connections. It is necessary to select proper materials (such as A102 welding rod.) and appropriate welding methods according to the welding procedures for dissimilar steels in combination with the contact medium. Welding metals is a touchy process. If you don’t weld with care, you could end up with destroyed piping or massive corrosion problems. Here are some factors to consider when welding metals.
① Welding requirements are implemented in accordance with the technical requirements.
② Different types of welding must be performed by welders with corresponding grades of stainless steel welder certificates.
③ To protect the surface of stainless steel products, it is strictly forbidden to cause arcs anywhere, and it is also strictly forbidden to hit the product with iron objects.
④ Temporary components that are welded with stainless steel should be selected according to the welding procedures for dissimilar steels in combination with the contact medium.
⑤ When welding stainless steel products, you must pick the right gas. Stainless steel is sensitive to atmospheric gasses, the inside of the pipe should be purified by inert gas, and the area near the weld must be continuously protected by argon gas during welding. That is not a minor detail, you must choose the right shielding gas and set the proper flow rates. The gas normally used for TIG welding is pure argon (Ar).
7. Use your metal brush to eliminate any dust, dirt, oil, grease, or water from your workstation. It is strictly forbidden to use iron tools for brushing.
8. Post-weld treatment: After welding, pickling and passivation treatment should be performed on the weld seam and the near seam area, such as cleaning with a weld cleaning machine.
To sum up, although welding stainless steel is a little more complicated than other welds, it can be done. You can even weld stainless steel to mild steel. Using the right equipment, managing your temperature, and getting the right filler material can produce a strong, durable weld.