ADVANCED MATERIALS & PROCESSES | SEPTEMBER 2025 23 APPLICATION AND DEMONSTRATION ABD-900AM has already exhibited a broad range of applications and improved performance through several demonstrations: Turbomachinery components: The alloy has been used to print complex microturbine components with thin walls and unsupported geometries, including eliminating the need for HIP. Rocket engine hardware: In collaboration with aerospace partners, ABD-900AM has been successfully printed into combustion chamber components, showcasing its ability to handle extreme thermal and mechanical loads (Fig. 2). Defense systems: The alloy’s high creep resistance and microstructural stability make it well suited for heat exchangers in integrated thermal management systems used for cooling in advanced military high Mach vehicles. like hot isostatic pressing (HIP) have shown potential in reducing defect populations. While these approaches have enabled limited application of such alloys, widespread adoption remains constrained by processing complexity and materials behavior. WANTED: HIGHERTEMPERATURE PRINTABLE AM ALLOY While IN718 has long been the workhorse alloy for AM applications, its performance begins to degrade above ~700°C, limiting its use in hot- section components of gas turbines, jet engines, rocket combustion components, and advanced heat exchangers— precisely where AM’s design freedom could offer the greatest benefits. To meet the demands of modern aerospace and energy systems, a new class of AM-compatible materials with high-temperature strength, oxidation resistance, and printability is needed. Using a computational alloy-by- design approach, ABD-900AM was engineered to maintain a high γ′ volume fraction (~35%) and optimized refractory content[3]. The result is a super- alloy with creep strength comparable to cast materials like IN738 and IN939, but with the added benefit of being highly printable using both laser and electron beam PBF systems. Over the past five years, extensive studies have been conducted on ABD-900AM to validate long-term high- temperature performance. These include validating printability in multiple build processes and machines, optimization of heat treatment, detailed microstructural characterization, and development of >70,000 hours of long-term creep data[4]. Key findings include: Enhanced printability: ABD-900AM achieves crack-free, high-density builds using both laser and electron beam powder bed fusion, overcoming the printability issues of traditional γ′- strengthened alloys. Elimination of HIP: The high build density of as-printed ABD-900AM eliminates the need for HIP, reducing post-processing costs, enabling shorter lead times, and simplifying the supply chain. Superior high-temperature performance: Through extensive creep testing (>70,000 hours), the alloy demonstrated excellent creep properties at temperatures to 900°C (1650°F). In comparison to IN718, ABD-900AM allows for an increase of ~125°C (220°F) for the same rupture strength. Microstructural optimization: Extensive studies were conducted to optimize heat treatment in ABD-900AM. A super-solvus heat treatment significantly improved creep life by promoting recrystallization and grain growth. Understanding damage mechanisms: Extensive creep testing evaluating laser and electron beam builds, including variation in build orientation and heat treatment, led to significant insights in understanding creep damage mechanisms (Fig. 1). Unlike cast materials, AM parts show variation in damage mechanisms based on build method and heat treatment. These include grain boundary sliding, cavitation, and damage from precipitate-free zones caused by carbide growth at grain boundaries. Prior studies failed to recognize these AM-related damage mechanisms. This work bridges a critical gap in the development of AM alloys for extreme environments. ABD-900AM offers a pathway to the advent of next-generation systems in aerospace and power generation by enabling the reliable use of AM in high-temperature applications. Fig. 1 — Improvement in creep properties for ABD-900AM compared to traditional superalloys such as IN718, IN625, H282, and additively manufactured IN939. Fig. 2 — ABD-900AM production parts for a static rocket combustion chamber (left) and rotating microturbine (right).
RkJQdWJsaXNoZXIy MTYyMzk3NQ==