Selecting the Right Material for the Job
Just as in any other type of manufacturing project, selecting the right powder metal material for use in production is important. Just like metals in their typical bar and sheets, the different types of powder metal have their own specific properties that lend each one to be useful in different applications.
The Metal Powder Industries Federation (MPIF) has set a number of useful and informative standards (MPIF Standard 35) for the use of different applications of powdered metals, specifically for self-lubricating bearings, steel parts, metal injection molded parts, and structural powdered metal parts. Most of the different types of PM parts fall into one of these four categories, and each has properties that lend the metal well to these end-uses.
The Different Powdered Metals
Typically, powdered metal is made from stainless steel, brass, copper, iron, or bronze, which can be blended with other alloys in order to get specific properties. Each one also offers different properties based on how they are formed, the particle size and chemical composition of the powder, and the shape of the powder particles.
Stainless Steel
Stainless steel is primarily made up of iron, nickel, and chromium, and it’s typically valued for its excellent corrosion resistance. Certain types of stainless steel powder also are magnetic, depending on the elements that they are blended together with. Stainless steel has a high melting point as well, and can be safely exposed to high operating temperatures. Typically it’s used in applications that require high strength, and corrosion and temperature resistance, such as automotive and aerospace parts, and various consumer goods and appliances.
Brass
Powdered brass is composed of copper and zinc, and as such is commonly used in electronics, thanks to its low friction coefficient and excellent corrosion resistance. It’s also excellent for applications that require good thermal conductivity and strength. Powdered brass is most often used to make parts such as gears, wheels, nuts, valves, fasteners, and similar components.
Copper
Powdered copper is best suited to electronics applications due to its excellent electrical and thermal conductivity. This metal’s high ductility and corrosion resistance have also made it popular in applications where structural parts regularly undergo strenuous operating conditions.
Iron
Iron/Steel PM components are made from reduced, atomized, or electrolytic iron powder, each with their own particular properties. Many are used in a wide range of automotive assemblies. Engine parts, steering and suspension assemblies, and transmissions all benefit from the properties of powdered iron. It’s also excellent for making other types of metal powders and alloys.
Bronze
Bronze parts are especially rigid and temperature resistant. Their high strength is suited to applications such as shock absorbers in automobiles, as well as bearings and bushings in various assemblies.
OTHER FACTORS TO KEEP IN MIND
While selecting the material for your next project, make sure to also keep in mind things like the tolerances that you need to meet and any secondary processing that may be required or that you’d be interested in. Certain materials like stainless steel already have excellent corrosion resistance for example, while others require further treatments to obtain that property. Metal powders can be mixed as well for improved durability, ductility, hardness, or other significant mechanical properties. The material standards set by the MPIF are an excellent resource for specific chemical makeups and mixtures of powder metal are best for different applications.
Looking for a powdered metal parts manufacturer?
Sterling Sintered Technologies, Inc. has been the leading fabricator of powder metal components since 1955. Check out our website today to learn more about what we can do for you.
