How does the grain structure of No-Tooling-Cost (Edgewound) spiral rings differ from stamped circlips?

Spiral retaining rings are produced by 'edgewound' coiling of pre-tempered flat wire. This process ensures that the grain flow of the metal follows the circumference of the ring. In contrast, stamped circlips (DIN 471/472) are punched from sheet metal, resulting in grain flow that runs transverse to the ring at two points. The circumferential grain flow in spiral rings provides superior toughness and fatigue resistance, as there are no 'weak' directions for crack propagation. Additionally, the edgewinding process eliminates scrap metal, making it more efficient for expensive materials like Elgiloy or Hastelloy.