11. Which of the following is not a ceramic-
A. Alumina
B. Whisker
C. Pyrosil
D. Porcelain
12. Tempering is a process of annealing-
A. martensite at low temperatures
B. martensite at a higher temperature
C. bainite at low temperature
D. bainite at a higher temperature
Read More- Welding Types and Definitions Notes
13. Which one of the following materials can be subjected to an age hardening process-
A. HSS
B. Stellite
C. Pure Iron
D. Aluminum
14. Windows of Aeroplane are made of-
A. PVC
B. PMMA
C. PTFE
D. PEEK
15. Cleavage fracture is a type of-
A. Brittle fracture
B. Ductile fracture
C. Elastic fracture
D. Viscoelastic fracture