Metallurgy in welding

Oftentimes I get a call from a customer that is trying to weld and is seeking some parameters to set to make the weld properly. I always start off by asking what type of metal they are welding. Sometimes I get a curious reply: "I stuck a magnet to it so it has to be steel". The customer is often shocked when I inform them that it also could be stainless or even cast iron. It seems that a lot of people are under the impression that all stainless is non-magnetic, which of course is not true.

This example demonstrates the need for a hobby welder to also be at least a hobby metallurgist. So many of the problems encountered early on in learning to weld are from ignorance about the properties of the metal they are welding on. No, no one needs to be an "expert" metallurgist to weld, but a welder needs to be studied in the basics of metallurgy to be all they can be, more than just someone who can strike and hold an arc. The welder needs to know the physical, and chemical makeup of what they are working on so that the most sound, and safest welds can be made.

There is no formal training course I could suggest for the hobby welder, however. I'd suggest hanging around old welding shops, and talking to seasoned veterans that are willing to pass on their knowledge in practical every day terms. Learning the difference between Martinsitic, and Austentitic steel, can make a difference in having a successful weld or not. Similarly the welder should know the basic differences between low and high carbon steel. The point of this blog is not to give details about metallurgy, but rather prompt the welder to go out and search out information for himself about each material. Being content to practice and weld on some mystery metal will cause more issues than it solves. So many welders find themselves frustrated when their welding practice doesn't improve their performance, because unknown to them, the "mystery" metal they are welding on isn't weldable, or the wrong filler is being used. Other sources of metallurgical knowledge can easily be attained from the filler material manufacturer themselves. The information contained within a box of welding rods, can yield a wealth of hidden knowledge about the welding rod's capability to join certain metals. Also, man online sources are easily accessed to find out or determine a metal's properties. Advanced knowledge of metallurgy isn't required, but some basic understanding is definitely necessary. A prospective welder should weigh this concern if they are thinking about stepping into the welding field even as a hobby. It's part of the leg work required to obtain satisfactory results. If this is too much to handle, then the person might want to move on to another hobby. There is nothing worse than a hobbyist who is pulling their newly welded trailer down the road, and watching it flip end over end in the rearview mirror, because he was ignorant of the metallurgical capabilities of the material used to put it together.