Here you can see the electron microscope image of a nickel alloy that has been specially optimized for 3D printing by US researchers. Because not every metal mixture is equally suitable.
3D printing has long since become part of everyday life in many areas of technology, research and industry. With its help, special components can be tailored and manufactured with little effort. One of the most common methods is laser melting. First, a layer of metal powder is applied to the printing surface, then a laser beam follows the path specified by the design and melts the powder at the desired points. This cools down and the metal object grows layer by layer.
For metal parts that are later exposed to heavy loads, however, the correct composition of the metal powder is crucial: If the mixture is not correct, the finished material can contain voids and defects in the metal structure. The reason for this are the different cooling rates of metals such as nickel, aluminum or magnesium. If the structure hardens too irregularly, tensions and defects occur in the structure, which reduce the strength.
This picture taken with an electron microscope shows a nickel alloy that was specially optimized for 3D printing by Raiyan Seede and his colleagues at Texas A&M University. “Our first goal was to make sure there were no pores in the printed metal parts, because that’s the obvious killer when you want to make objects with good mechanical properties,” explains Seede. “Based on this, we have now gone deep into the fine-tuning of the microstructure of the alloys so that we have even better control over the properties of the finished component.”
The researchers initially used 3D printing tests to gradually find out the optimal metal mixture and the best combination of the laser intensity and the speed of the laser beam. Then they use adaptive algorithms in order to be able to transfer the optimal parameters to other metals and alloys. “Our results could be of great benefit to aviation, vehicle construction and other areas in which customized metal components are required,” says Seede’s colleague Ibrahim Karaman.