Official Answer
Answer
Elgiloy is specified for spiral retaining rings in extreme environments like downhole drilling or medical heart valves. It offers a unique combination of extremely high fatigue strength and resistance to virtually all corrosive media. Its modulus $E = 200$ GPa is similar to steel, but its endurance limit is significantly higher. The material is typically provided in a cold-worked and aged condition. For biomedical use, its biocompatibility and non-magnetic properties make it ideal for MRI-compatible surgical instruments.
