Almost every form of additive manufacturing, or 3D printing, involves the use of different powders. Powders vary from metal to plastic, with different subsets of metal powders to choose from. The type of metal powder you ultimately decide on is directly connected with the quality and efficiency of the final 3D printed product. Since a ‘one size fits all’ approach is out of the question, here’s a look at the best metal powders you can use for your 3D printer.
What Makes For a Good Metal Powder?
3D printing machines generally work under pre-set conditions. This means that they lack the ability to account for imperfections in the input material. This becomes a concern for 3D printers that are working with metal powder that is impure or contains even the smallest imperfections. Ultimately, failing to pick the right metal powder can lead to fragile and unreliable products.
No two batches of metal powder are created the same, and manufacturers must consider several factors when searching for the perfect product.
- Sphericity: The sphericity of a metal powder is one of the first considerations with 3D printing. The sphericity determines how high the packing density of the final product will be. Metal particles that are more spherical will pack more efficiently than those with angularities. The more densely packed the particles are in the product, the more stable it will be. This makes the sphericity of the powder a crucial consideration for industrial 3D printing.
- Flowability: The overall efficiency of a 3D printing service is directly dependent on the flowability of a metal powder. Flowability refers to the ease with which the input material can be manipulated by the 3D printer. Materials that have higher flowability can easily be used to create consistent layers and are less likely to create irregular products.
- Properties: Both chemical and physical properties can vary drastically across different metal powders. 3D printing with aluminum powder, for example, can make for more malleable products than titanium powder, which, in turn, is more suitable for components that need to maintain their shape over an extended period of time despite external pressures. Manufacturers have to evaluate what properties they’re looking for in a powder, as the “best” option depends on the application.
Steel has been used in industrial manufacturing since well before the invention of 3D printing. The longstanding use of steel makes it an abundant and relatively inexpensive powder for 3D printing. The growing trend of steel recycling means that manufacturers can expect even lower prices for materials down the line if circular manufacturing becomes a reality.
‘Steel’ itself is an umbrella term that encompasses different alloys and types of steel. Stainless steel is a popular variant that has both commercial and industrial applications. The material is known for its high durability under extreme conditions and for its long-term corrosion resistance. For reference, standard stainless steel is over three times as strong as aluminum.
Steel metal powder can be used to manufacture anything from high-volume spare parts to intricate prototypes that require precision printing. An exciting development here is the use of 3D printing to create stainless steel implants for medical use. Due to its excellent resilience, this metal powder can be reliably 3D printed for long term medical applications without fear of breakage.
Even outside of 3D printing, aluminum is known for its lightweight properties. This property also translates to aluminum metal powders with 3D printing. The balance of weight and resistance to corrosion makes aluminum a commonly used material in industries that require a great degree of precision, such as aerospace and medical. The increasingly affordable and reliable nature of aluminum powder as a 3D printing material has even resulted in it being approved for use in Formula 1 automotives.
As far as different types of additive manufacturing, aluminum powder is suitable for use both in Direct Metal Laser Sintering (DMLS) and Selective Laser Melting (SLM).
Historically, titanium has been an excellent material for industry-grade markets, with nigh-unbeatable tensile strength. The properties of titanium make it the first choice for industries that require material that can stand the test of time and the elements while maintaining its original shape.
The biggest downside to using titanium as a powder for 3D printing is the fact that it can be quite expensive relative to other options like steel or aluminum. Prices for titanium metal powder have gone down significantly since its advent thanks to advances in printing technology—however, manufacturers will still have to weigh whether or not they need all the strength titanium offers.
Great Powder, Great Products
Picking the right powder is essential to meet today’s high 3D printing standards, and it begins with an understanding of what they all bring to the table. Distributors like KBM are making it easy for even smaller manufacturers to source high quality powders. Explore our expansive selection and upscale your manufacturing today.