In the ever-evolving landscape of materials science and additive manufacturing, a groundbreaking study from the National Institute of Technology, Tiruchirappalli, India, is set to redefine the capabilities of titanium alloys in structural applications. Led by Shivakumar N. from the Department of Mechanical Engineering, this research introduces a novel technique that could significantly enhance the performance of Ti6Al4V, a workhorse material in industries ranging from aerospace to energy.
The study, published in Materials Research Express, focuses on a new approach called node compensation (NC) for Ti6Al4V-based diamond metal lattice structures (MLSs). This method aims to reduce stress concentration at strut junctions, a common weak point in lattice structures, while simultaneously boosting their energy absorption capacity. The technique involves removing one spherical node from a representative volume element (RVE) and compensating by increasing the diameters of the remaining nodes. This adjustment not only improves porosity but also mitigates stress concentration factors, making the structures more robust and efficient.
The implications for the energy sector are profound. As the demand for renewable energy sources grows, so does the need for durable, lightweight, and efficient materials for structures like wind turbines and solar panels. Ti6Al4V, with its excellent strength-to-weight ratio and corrosion resistance, is already a popular choice. However, the stress concentration at strut junctions has been a persistent challenge, limiting its full potential. The NC technique addresses this issue head-on, paving the way for more resilient and efficient energy infrastructure.
“The NC structure exhibited an extended plateau stress region in the 100–150 MPa range with more uniform deformation,” Shivakumar N. explained. “This means the material can absorb more energy before failing, making it ideal for applications where durability and longevity are crucial.”
The research team modeled the NC structure and two purely strut-based designs (D1 and D2) in SolidWorks and fabricated them using the direct metal laser sintering (DMLS) technique. The structures were then validated through micro-CT imaging, and their phase composition was analyzed using scanning electron microscopy (SEM), electron backscatter diffraction (EBSD), and x-ray diffraction (XRD). Quasistatic compression tests, combined with digital image correlation (DIC), revealed that the NC structure outperformed D1 and D2 in terms of yield strength, ultimate strength, and quasielastic gradient (elastic modulus).
The NC structure demonstrated a yield strength of approximately 150 MPa, an ultimate strength of 200 MPa, and an elastic modulus of 3.572 GPa. These properties align closely with those of cortical bone, suggesting that the NC technique could also have applications in biomedical engineering.
The study, published in Materials Research Express, which translates to Materials Research Express, marks a significant step forward in the field of additive manufacturing and materials science. As the energy sector continues to push the boundaries of what’s possible, innovations like the NC technique will be crucial in meeting the challenges of the future.
The research opens up exciting possibilities for the future of Ti6Al4V and other titanium alloys. As Shivakumar N. puts it, “This is just the beginning. We’re excited to see how this technique can be further refined and applied in various industries.” The potential for more durable, efficient, and sustainable structures is immense, and this study is a significant stride towards that goal. As the energy sector continues to evolve, so too will the materials that support it, and the NC technique is poised to play a pivotal role in that evolution.