Hannah Luben is a Mechanical Engineering student at Penn State who got to experience a new technology in her senior capstone project: metal 3D printing. Through a partnership with Xact Metal, Hannah optimized print parameters, gained advanced technical knowledge, got offered an internship, and built job-ready skills she can take into her career.
Metal 3D printing was once something of the future, a scarce technology that very few had access to and understood. Today, industries like aerospace, engineering, dentistry, audiology, healthcare and manufacturing all use metal 3D printing to create lightweight, custom parts. The technology allows companies to produce onsite instead of waiting weeks or months for custom parts to arrive. As metal 3D printing becomes more common in the workforce, employers will need engineers who understand the complexities of metal additive manufacturing: how to choose the right material for the job, designing parts for additive, how to optimize print bed space, and how to eliminate any waste from the process.
Today, the skills gap is on everyone’s mind: employers are looking for experience when hiring candidates in skilled roles, and as a result many schools have focused on ways to implement more interactive learning. Leading engineering universities understand the importance of hands-on learning. They’ve invested in cutting-edge technology. They focus on practical application of engineering concepts. They have students do collaborative projects with local companies.
At these universities, students get to practice what they’ve learned, furthering their understanding of their field. They get the opportunity to make mistakes in a safer environment and gain confidence in their skills. And that reduces the learning curve when they enter the workforce. Penn State University is one of these leading schools, and Hannah Luben is one of these fortunate students.
As Hannah, a mechanical engineering student, approached her final semester, she, like all engineering students, had to complete a senior capstone project. Engineering students were tasked to work in collaborative teams alongside a company located in the area to design and build a solution to a problem.
Getting connected with a local company was easy, since Penn State has the unique advantage of being home to Innovation Park. It’s 118 acres of office, manufacturing and research space where education, business and research collaborate on startups and innovative initiatives. One of those startups is a company called Xact Metal, a manufacturer of metal 3D printers. With no prior 3D printing experience, but intrigued by the concept, Hannah chose to work with Xact Metal for her project.
Xact Metal was founded in Innovation Park in 2017. They knew that 3D printing would continue to emerge as a key technology for manufacturing, but saw how difficult it was for educators and businesses to fund and install metal 3D printers. With innovation at the forefront of their company, Xact Metal designed and built metal 3D printers that are affordable, accessible, and have a short time to adoption, all while maintaining the print quality and speed of other metal 3D printers.
Chief Executive Officer Juan Mario Gomez was featured on The TechEd Podcast, where he talked about the founding of the company and their unique value add to the university space:
It was only fitting, then, that the metal 3D printing company, founded and launched at Innovation Park, would partner with engineering students to improve their products and processes. This is what Hannah and her team got to experience in their capstone project.
Xact Metal uses powder-bed fusion technology, a process by which metal powder is added to the print bed and then fused by a laser layer by layer. Other metal additive methods require a wash and sinter process post-print to complete the part and achieve desired density. This requires additional machines and often construction to the building for proper ventilation. The advantage of Xact Metal’s method is that the printed part is complete after this one step, on a single machine.
When printing in metal, there are specific parameters for each material that optimizes the print capabilities of that particular metal. The objective of Hannah’s capstone project was to optimize the parameters of Xact Metal’s XM200C printer for printing in 17-4 stainless steel. The industry-standard density for 17-4 stainless steel is 99.5%, a high target to hit. To achieve this density, the team would need to adjust the laser speed and hatch spacing.
Hannah explained why these two factors are so important: “The way that powder bed works is it takes a laser and it fuses metal powder in layers. So the speed at which that laser moves is very important for optimizing these parameters. And the hatch spacing: if you have a circle that you’re filling in, you’re going to take a zig-zagging pattern to fill that in…the distance between those consecutive passes of the laser is called the hatch spacing. So these two items we took and we looked at different ways to optimize them to get the highest density that we possibly could in our printed parts.”
To methodically measure the various combinations of speed and hatch spacing, the team would create a matrix with different speeds and different hatch spacings. They would print nine density cubes with pointed ends (see picture), each with a different combination. After printing, the team would test the cubes’ densities using an Archimedes scale. They did this over and over again, refining the parameters until they achieved the highest density possible.
After finding the right combination, Hannah and her team were able to achieve 99.8% density printing 17-4 stainless steel.
After completing the capstone project, Xact Metal was impressed with her performance and invited Hannah to continue her work in an internship that summer. So Hannah spent the summer using this same method to optimize several other metals, including a 400 series, 15-5, and 4130 stainless steel. After her internship, she even considered getting a minor in additive manufacturing, an area that she never considered before completing this internship.
Today, Hannah continues her education at Penn State University pursuing a masters degree in mechanical engineering. While she may or may not pursue a career in a sector that utilizes metal 3D printing, her experience in her capstone project will certainly stay with her throughout her career. Not only the technical 3D printing skills, but the teamwork and collaboration, problem-solving, testing and data analysis skills that can be applied to any engineering role she may have in the future.
In her words, “it was the most valuable part of my schooling.”
What can we learn from Hannah’s story? Consider these takeaways:
Benefits for the student: Hannah gained workplace ready skills and technical skills from a single project. She was able to be value-added in her internship on day 1 because she was already skilled in the work she would be doing. This experience sparked Hannah’s interest in additive manufacturing, an area she had never thought of pursing.
Benefits for the employer: Xact Metal had a high-priority challenge solved for them (and not just solved…but above and beyond industry standard!). They developed a great reputation with skilled students in the region – and ended up with an intern who could provide value from the first moment she started her work.
Universities across the country are starting to do what technical and trade schools have been doing all along – focusing on hands-on learning first and foremost. Remember, the first day on the job should not be the first time an engineering grad touches industrial equipment. We would love the day to come when employers stop saying, “it takes a year or two for four-year engineers to be any use because we have to teach them how to turn a wrench.”
Educators: let’s build and expand programs that foster hands-on, practical and applied learning.
Employers: let’s develop partnerships with schools to help direct, support and create pathways for engineering students.