As a technician from manufacturing industry, I often face queries from my known persons in the industry and outside of it. One question was related to the welding of a stainless steel not with carbon steel wire.
Experienced technicians across the manufacturing industry can easily answer this query with a simple reply, Yes. For the welding, the expert performing the job will require a corrosion-resistant wire form. You need to avoid matching or mixing metals.
How to weld different metals
Austenitic stainless steel, like grade 316 or of lower grade can easily be welded to plain carbon steel with the use of TIG and MIG welding. When it comes to weld stainless steel to a different metal, like plain carbon steel, weld methods, like MIG welding which utilize filler material, are preferred.
Commonly, conflict welding of carbon and stainless steel is not done due to distinguishes in electrical conductivity between these two metals make it hard to reach the right welding temperature. For the confronted welding, preheating of carbon steel is usually done to lower the electrical conductivity and speedup the heating.
How the welding of stainless steel with other materials is done
As a technician, you should opt for other welding types and avoid confronted welding when you have to weld stainless steel with any other metals. For example, prefer TIG and MIG welding types when you have to weld stainless steel to carbon steel. When it comes to weld two different metals, such as carbon steel and stainless steel, together, utilize a filler material for binding these two dissimilar metals. In MIG welding, you need to melt a incessantly-fed electrode wire into the weld to enable two different metals to have a concrete bind without heating them at the melting points.
Technicians program an MIG welding robot to execute the job with the advancement of stainless steel with MIG. They use a filler material at the melting points to two dissimilar. For example, if one metal gets overheated to reach the melting point in comparison with other, there might be cracks and micro fractures as outcomes.
Why to avoid the welding of stainless steel with carbon steel
Stainless steel and carbon steel are two dissimilar metals. Welding one to another can confront and cause several issues. Here are a few reasons that clearly state to avoid welding stainless steel with carbon steel:
Difficulty
Bringing two different metals, like carbon steel and stainless steel, increases the challenges of the process. Due to this, there is an increase in rejection/error rates and labor costs.
Hot cracking
Stainless steel is more electrically resistant in comparison with carbon steel. So, welding the first to the second makes the first one get heated faster in comparison with the second one. While waiting for the second metal to get the weld temperature, the first metal (stainless steel) gets overheated, causing cracks in it.
Thermal expansion
Thermal expansion is also a problem of welding two dissimilar metals, such as carbon steel and stainless steel. This expansion affects both metals, and the differences in thermal expansion can lead to have additional fatigue at the melting/welding point, and this fatigue can reduce the structural form and usability.
Enhanced bimetallic corrosion
Most of you love using stainless steel due to its strong resistance to corrosion. A bare weld of plain metal has exposure to tremendous corrosion situations, like concentration in salt water, could lead to have corrosion. It will happen due to the mixing of plain steel particles with stainless alloy that compromises the protective oxide layer of the stainless steel.
Decreased weld strength
Welding two different metals can lead to have weaker welds, even using a filler material. The distinctions in operational tolerances and weld temperatures can easily concession the compactness of the welded joints.
Conclusion
When it comes to welding, many people take it lightly. Being a manufacturer, you should consider a lot about the confronted welding and opt for the best procedures for welding. In the case of part punching, you can contact a manufacturing partner with punching facility.
