May 2025 Volume 7

MATERIALS

Although these materials present challenges in forging due to their high deformation resistance and narrow processing windows, they remain indispensable in critical applications, including aerospace, medical, military, and industrial environments. While both titanium and superalloys offer superior strength, corrosion resistance, and heat tolerance, they require precise temperature control and specialized forging techniques. The ability to forge these advanced materials ensures continued innovation and reliability in demanding conditions. References 1. https://www.nature.com/articles/s41598-017-07884-4 2. https://weldaloy.com/superalloys-inconel-forgings/

Common Titanium Alloy Grades • 6-4 (Ti-6Al-4V): The most widely used titanium alloy, particularly in aerospace components. • 6-2-4-2: Known for excellent creep resistance and high temperature strength. • 6-2-4-6: Offers improved toughness and ductility compared to 6-2-4-2. • 3-2.5: Notable for outstanding weldability and corrosion resistance, making it a common choice for medical implants. Forging Techniques for Titanium • Controlled Atmosphere Forging: Due to titanium’s high reactivity with oxygen, nitrogen, and hydrogen at elevated temperatures, forging is often conducted in an inert atmosphere or with protective coatings to prevent contamination. • Optimal Temperature Range: Titanium alloys must be forged within specific temperature ranges to avoid cracking or excessive grain growth. Ti-6Al-4V, for instance, is forged between 900°C and 980°C. • Rapid Cooling: Unlike superalloys, some titanium alloys benefit from rapid cooling post-forging to retain desirable microstructures and mechanical properties. • Machining Considerations: Post-forging machining is often required for forged titanium components due to their high strength and difficulty in achieving final shapes solely through forging. Conclusion Forging remains an essential process for shaping titanium and superalloys into high-performance components. Superalloy applications our industry serves include oil and gas, air travel, chemical processing facilities, space travel, and other industries with parts operating in severe environments. Superalloys (e.g., Inconel, Hastelloy, Waspaloy) • Extreme heat resistance – Used in jet engines, turbines, and exhaust systems. • Oxidation and corrosion resistance – Performs well in harsh environments such as saltwater or chemical exposure. • High strength and creep resistance – Retains integrity under extreme stress and prolonged heat. Titanium • High strength-to-weight ratio – As strong as steel but about 45% lighter. • Corrosion resistance – Ideal for aerospace, medical, and marine applications. • Biocompatibility – Commonly used in medical implants and prosthetics. • High temperature resistance – Maintains strength at elevated temperatures.

FIA MAGAZINE | MAY 2025 45