Post Doctoral Research Fellow Cleveland State University
Forged components serve as the backbone of the aerospace, automotive, and defense industries, where exceptional strength, dimensional stability, and fatigue resistance are essential. However, the forging dies used to shape these components operate under extreme cyclic thermal and mechanical stresses, resulting in surface cracking, thermal fatigue, and severe wear. These degradation mechanisms frequently cause die failure and costly production downtime. This study investigates the application of arc- and laser-based Direct Energy Deposition (DED) processes as viable and sustainable solutions for restoring worn or damaged forging dies, offering an advanced alternative to conventional welding-based repair methods. Multiple advanced, industry-grade repair alloys, including Fe-based Eureka 450, Co-based Eureka MF-201 (Stellite type), and Ni-based Inconel 718 and Eureka CWD (Waspaloy type), were deposited on H13 tool steel substrates using an automated DED system. The repaired blocks were subsequently evaluated through comprehensive microstructural characterization and mechanical testing to assess process integrity and interfacial performance. The results confirmed strong metallurgical bonding between the deposited repair layers and H13 substrates. Ni-based Eureka CWD showed superior interfacial performance, achieving a tensile strength of 92 ksi and 16% elongation. This improvement is attributed to its stable austenitic matrix, where nickel acts as an FCC phase stabilizer, promoting microstructural stability and strong metallurgical bonding between the repair alloy and the H13 substrate. In contrast, Fe-based Eureka 450 repair alloy demonstrated higher bulk strength (187 ksi) and hardness (~400 HV), suitable for high-stress, wear-resistant die regions. These results highlight the complementary mechanical behavior of each repair alloy, enabling optimized material selection for specific forging conditions. Building on these insights, the approach will be extended to full-scale, complex real forging dies under industrial conditions. Overall, the study establishes arc-based DED repair as a scalable, cost-effective, and sustainable solution for extending die life and minimizing lead time for the forging industry.
