3D printing is often associated with plastics, but metal powders tailored to specific additive technologies are emerging rapidly to keep pace with applications in several industries. The quality and composition of these metal powders can be controlled using X-ray fluorescence (XRF) elemental analyzers. Formulations include some grades of stainless steel, low alloy steels, nickel and cobalt alloys, and titanium powder that can be used to 3D print automotive, aerospace, and defense components.
Titanium alloys are valued in these industries for their high tensile strength, light weight, corrosion resistance, and ability to withstand extreme temperatures. It is these properties that have inspired car manufacturer Bugatti to design a titanium brake caliper that can be produced by 3-D printing.
According to the Bugatti web site, the new brake caliper is the world’s largest functional component produced from titanium using 3-D printing processes. The titanium alloy used to make the caliper (Ti6AI4V) offers considerably higher performance than aluminum. Even as a 3-D printed component, it has a tensile strength of 1,250 N/mm2 but it weighs approximately 40% less than the aluminum component currently used.
Because titanium is so strong, it’s not possible to forge components in the conventional production process used with aluminum. Using an extremely high-performance 3-D printer opens up new possibilities with the metal. The Bugatti press release explains the process as follows:
It takes a total of 45 hours to print a brake caliper. During this time, titanium powder is deposited layer by layer. With each layer, the four lasers melt the titanium powder into the shape defined for the brake caliper. The material cools immediately and the brake caliper take shape. The total number of layers required is 2,213. Following the completion of the final layer, the remaining titanium powder which had not melted is removed from the chamber, cleaned and preserved for reuse in a closed loop. What remains in the chamber is a brake caliper complete with supporting structure which maintains its shape until it has received stabilizing heat treatment and reached its final strength.
3D printing with metal still has limitations. And like traditional metal manufacturing, the success of 3D printing with metal powders depends on having the right alloy for the application. For example, titanium is added to steel alloys to reduce grain size and as a deoxidizer, and in stainless steel to reduce carbon content. Titanium is often alloyed with aluminum to refine grain size, with copper for hardening, and with precise amounts of platinum, palladium, or ruthenium to make pipes that can withstand harsh chemical processing environments. The quality and chemical composition of all of the metals that go into making these blends must be verified using elemental analysis systems.
Wavelength-dispersive x-ray fluorescence (WDXRF) and energy-dispersive x-ray fluorescence (EDXRF) are elemental analysis technologies that easily and positively characterize any metal powder. Laboratory-based XRF analyzers and systems can evaluate all kinds of materials and sample types for qualitative and quantitative analysis for process and quality control in a variety of metallurgical applications.