How to Identify a Metal

How to Identify a Metal
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It can be very important to accurately identify types of metal when working with metal materials, and this is particularly important in maintenance welding. Proper identification of base metals helps minimize downtime and ensures maximum confidence of producing strong and high quality welds for any project that involves working with metal.

Metals with higher carbon content are sensitive to hot-cracking and hardening, which can result in poor ductility for welding projects. If you want to simply identify a piece of scrap metal, you can do this by evaluating its color, weight and composition.

    Take your piece of metal and test its magnetization by sticking a magnet to it. If your metal sticks to the magnet, the metal could be cast iron or steel. If the metal does not stick to the magnet, your metal could be copper, brass, solver or aluminum.

    Determine whether or not your metal is steel metal by looking at the color of the metal. Short and long steel are often have a dark brownish color, while stainless steel is shiny, silver and very bright.

    Consider the color again if you determine that the metal is not steel. If the metal has a brightly colored reddish tint to it that is relatively shiny, the metal is most likely copper metal. When copper is exposed to the elements, it turns green.

    Look for any signs of yellow coloring on the metal. Copper and brass can often be confused with each other. Remember that copper is mostly red and brass is mostly yellow.

    Look for signs of shiny, silvery colors with metals that are softer and more flexible than other metals. If you see these characteristics, you may have aluminum.

    Check your metal by applying the magnet test again if you suspect that the metal is aluminum. Aluminum and tin can be mistaken for one another, but tin will stick to a magnet while aluminum will not. Tin also has a similar color to aluminum but shows a slightly duller finish.


    • As an additional test, you can perform a file test for faster and easier metal testing. A file test can be performed using any workshop file to determine the carbon content of any unknown type of steel without the need for special equipment or chemicals.

      A chipping test is another method of identifying an unknown metal by chiseling off a small piece and evaluating the color and the composition of the chip.


    • Large pieces of metal can be very heavy. Do not attempt to lift any large pieces of metal that you think you cannot handle.