The present study examined plastic deformation behavior of a biomedical-grade Co-29Cr-6Mo (wt.%) alloy at intermediate temperatures, focusing on dynamic strain aging (DSA) induced by nitrogen doping (0.2wt.%). The compression tests were performed at strain rates in the range of 10 -4 to 10 -1s -1 at temperatures between room temperature and 1073K. Gliding of Shockley partial dislocations bounding stacking faults played a dominant role in the plastic deformation over a wide temperature range. The nitrogen-associated DSA resulted in enhanced in-grain lattice distortions even when there was little macroscopic serrated flow. Shear band formation was identified after the lamellar structures developed, in spite of quite small macroscopic strain (5% in height reduction). Cr-N short-range ordering can be responsible for the observed DSA.
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