Working with metals just got a lot more exciting. Researchers from Texas A&M University have discovered a method of 3D printing extremely hard steels flawlessly.
This method of printing martensitic steel proves extremely useful for industries such as aerospace, automotive, and defense, as this type of steel naturally lends itself to their applications. Thanks to these researchers, there is now a way of printing these high-strength steels that are lightweight, that is cost-effective.
Their findings were published in the journal Acta Materialia in December.
Metals built into complex structures
Building these metals into complex structures without losing much of their durability and strength has been at the forefront of many a metallurgist's minds. Thanks to the Texas A&M University team, who worked in collaboration with the U.S. Air Force Research Laboratory, guidelines for 3D printing martensitic steels into extremely sturdy and defect-free objects have now been developed.
"Strong and tough steels have tremendous applications but the strongest ones are usually expensive — the one exception being martensitic steels that are relatively inexpensive, costing less than a dollar per pound," said Dr. Ibrahim Karaman, Chevron Professor I and head of the Department of Materials Science and Engineering.
"We have developed a framework so that 3D printing of these hard steels is possible into any desired geometry and the final object will be virtually defect-free."
What's even more exciting is that the researchers have developed a method that not only works for martensitic steels but also for other metals and alloys.
The biggest challenge the team faced was ensuring their 3D printed steel objects were defect-free, as this way of printing tends to lead to such defects occurring in the pores of the material. "To find practical applications for the new martensitic steel, we needed to go back to the drawing board and investigate which laser settings could prevent these defects," explained Karaman.
"Testing the entire range of laser setting possibilities to evaluate which ones may lead to defects is extremely time-consuming, and at times, even impractical," said Raiyan Seede, a graduate student in the College of Engineering and the primary author of the study. "By combining experiments and modeling, we were able to develop a simple, quick, step-by-step procedure that can be used to determine which setting would work best for 3D printing of martensitic steels."
As Karaman noted "Although we started with a focus on 3D printing of martensitic steels, we have since created a more universal printing pipeline."
"Also, our guidelines simplify the art of 3D printing metals so that the final product is without porosities, which is an important development for all type of metal additive manufacturing industries that make parts as simple as screws to more complex ones like landing gears, gearboxes or turbines."
A useful development indeed.