Which Metals Can Be Welded and Why?

Weldability is everything. Metals with a high weldability are easier to weld and retain a higher weld quality than other metals, so it’s important to study these factors before choosing materials for a project.

Once you’ve narrowed down your selection to a few metals, the next step is to determine which welding process you’d like to use. Some methods require more skill than others, such as TIG welding — and these will affect which metals are at your disposal. For example, the ideal metals for MIG welding are carbon steel, stainless steel, and aluminum, all for different reasons.

The main parameters that determine a metal’s weldability include the electrode material, cooling rate, shielding gases, and welding speed. Every metal is unique. To a certain extent, all metals can be welded, but there are clear advantages and disadvantages to each.

Stick welding, also known as shielded metal arc welding (SMAW), is one of the most common welding methods out there. To get started, you’ll need a welding machine, a proper electrode (we recommend DCEP for DC welding), a safety helmet, clamps to hold the joints together, and your welding metal of choice. With this method, you are melting a metal rod with a special flux coating that prevents oxygen contamination — hence the “shielded metal” name. Stick welding can be used to weld steel, iron, aluminum, copper, and nickel.

Unlike stick welding, gas metal arc welding (or GMAW) does not have a coating over the electrode rod. Instead, the welding gun disperses a shielding gas that protects against contaminants. It’s the most common industrial welding process today, and can be used for steel, cast iron, magnesium, and many other metals.

Ultimately, there is no clear-cut answer when deciding which metals and welding methods to use. It’s best to figure out which metals are best suited (and most cost-effective) for your project, and then decide on a welding style that can be performed with your skill set.

Which Metals Are Magnetic?

Discovered by ancient civilizations around 500 BC, magnets have become an essential component in modern technology. Demand for magnets continues to grow as smartphones and other electronic products become ubiquitous. But which metals can engineers use to create a magnetic force? There are four main magnet types:


To start, diamagnetic metals are weakly repelled by permanent magnets. Typically made from nickel or iron, permanent magnets retain magnetism after being influenced by an external magnetic field. On the other hand, diamagnetic metals include copper, lead, and graphite. Although they make a weak contribution to magnetic fields — since they barely react with permanent magnets — they are magnetic metals nonetheless. To a certain extent, all materials experience some form of diamagnetism, including trees and clothing.


Next, superconducting metals create a strong repulsion in permanent magnets. These include gallium and tin. All superconductors need to be at an extremely cold temperature (known as the “critical temperature”) for magnetic repulsion to take place. Once the superconductor metal breaches this temperature, it reaches a point where there is zero electrical resistance. Other metals may be conductors, but their impurities prevent them from reaching zero resistance.


On the opposite end of polarization, paramagnetic metals are weakly attracted to permanent magnets. Most chemical elements display some degree of paramagnetism, which means they have a positive susceptibility to magnetic fields. However, if there is no external magnetic field influencing them, paramagnets will not have any magnetization. Paramagnetic metals include gold and aluminum.


Finally, ferromagnetic metals have a strong attraction to permanent magnets. When we observe magnetic attraction or repulsion in daily life, we are seeing ferromagnetic materials in action. Only a few metals are ferromagnetic, however, and these include iron, cobalt, nickel, and some rare earth metal alloys. These materials form the basis of many electric products today, such electric motors, hard disks, generators, and much more. Most permanent magnets are ferromagnetic.

How to Rust Metal

It’s understandable that most people want to prevent their cars and power tools from rusting, but some steel objects actually gain character from having a nice rusty patina. With a few household chemicals, it’s easy to speed the oxidation process along. Below, we’ve shared the basic steps to give your outdoor decorations a charming, weathered look.

  1. Buy Materials: You might already have some of these products in your pantry, so scan through the house before buying anything. To give your steel that rusty finish, you’ll need table salt, white vinegar, and degreaser, along with measuring cups/spoons and a spray bottle. We also recommend you buy a new bottle of hydrogen peroxide, instead of using an old one in your medicine cabinet. For safety purposes, you should be wearing goggles and chemical resistant gloves at all times. Remember, you’re going to be combining harmful chemicals, so be careful!
  1. Degrease the Steel: After stripping your steel of any coating or paint, the metal will be ready for degreasing. Read the degreaser bottle’s instructions as you apply it to the metal, and take care not to touch it with your bare hands. You want the degreaser to work its magic, but you don’t want to add more oil and dirt in the process.
  1. Pickle the Steel: Yes, the next step is just like pickling cucumbers, only here you’re pickling steel. This helps to create a uniform coat of rust, instead of certain areas being rustier than others. Pour some white vinegar into the spray bottle and then spray every inch of the metal object. Let it dry in the sun, and then repeat several more times. Now, your steel will be ready for the main event.
  1. Make It Rusty: So you’ve prepped the metal object for rusting, but how does the oxidation process actually happen? First, you’ll need to create a rusting solution by combining 16oz hydrogen peroxide, 2oz white vinegar, and ½ tablespoon of salt. If possible, mix this solution in the spray bottle with some of the leftover white vinegar. Shake it up so that everything mixes well, and then start spraying down your object. If the rusting doesn’t start happening immediately, you may need to put your object in direct sunlight for a while. Heat helps the process.

After you spray the metal, let it dry, and then repeat for about 7 cycles, your steel should look like it’s aged years. Make sure you don’t touch the rust until it has fully dried out, because it might rub off. The longer it stays in the sun, the better.

How to Stop Rust

Rust on any object — whether it’s a car, power tool, or a bridge — is an unattractive and often dangerous phenomenon that should be prevented whenever possible. Typically, rust occurs when metal is exposed to water and oxygen for a prolonged period of time. Iron and oxygen combine to form iron oxide, whose properties create the flaky orange-yellow coating that we all know as rust. The initial corrosion is fairly easy to remove, but wait too long, and you’ll have a car destined for the junkyard. Below, we’ve outlined five approaches to defeating rust before it spreads.

  1. Bluing: By dipping metal objects into a solution of water, sodium hydroxide, and potassium nitrate, you give them a strong corrosion resistance. This technique is often used with guns and clocks, and the name refers to the metal’s bluish finish when immersed in the solution.
  1. Clean Your Car Regularly: It may go without saying, but washing and waxing your car is extremely important for rust prevention. Dirt can also accumulate underneath your car over time, retaining moisture, so it’s smart to spray the undercarriage often as well. Although new cars are coated with the latest chemicals to fight against rust, vintage vehicles require an attentive eye to ensure that they remain drivable.
  1. Invest in Rust Prevention Products: These over-the-counter chemicals can be found in a variety of application styles — from aerosol sprays to cloth wipes. It all depends on the object you’re trying to protect. For small tools and outdoor gear, we recommend the Sentry Solutions TUF-CLOTH. For vehicles and larger metal parts, the Boeshield T-9 aerosol can was originally designed by Boeing Aviation for their aircraft components, so it does the job.
  1. Install a Dehumidifier: By controlling the exact amount of moisture in the air, you can slow down the oxidation process in your garage, basement, or any other sealed work space. If you own or work with valuable metal objects, it’s definitely worth the small initial investment.

5. Scrape Off Rust Immediately: Rust spreads like an infection, so it’s important to deal with oxidation as soon as it appears. To help slow down the process, you can scrape off loose rust pieces with a razor blade and then scrub the affected area with warm water and soap. Finally, apply a metal conditioner to prevent further rusting, and then put a new coat of paint on the area (if necessary).