Q1. Attempt all questions. The marks for each question are indicated against it.
- (a)) Explain with diagram, how many identical points are created by a 3 roto-inversion operation. Among 3-fold rotation and 3 roto-inversion operation, which one has higher order? Why? (250 words)
- (b)) What are glassy alloys? Discuss their mechanical properties vis-à-vis normal metal alloys and ceramic oxide materials. State any four technological applications of glassy alloys. (250 words)
- (c)) What are solid solutions? Explain the rules (Hume-Rothery) governing the formation of substitutional solid solutions. (250 words)
Key Points:
- 3 roto-inversion (S₃) creates six distinct points before returning to the original state.
- S₃ has a higher order (6) than 3-fold rotation (C₃, order 3) due to inversion.
- Glassy alloys are amorphous metals lacking long-range crystalline order.
- Glassy alloys exhibit higher strength/elasticity but can be brittle compared to crystalline metals.
Answer: