Option 25
1. Which of the most common metals have a bulk-centered cubic
Lattice? Draw an elementary cell, specify its parameters, coordination number.
2. Indicate the purpose and selection of the recrystallization annealing mode. Consider on
Example of aluminum.
3. Draw a state diagram of iron-iron carbide, indicate the structural
Components in all areas of the diagram, describe the transformations and construct a curve
Cooling (using the phase rule) for an alloy containing 3.5% C. What is the structure of this
Alloy at room temperature and how such an alloy is called?
4. In the structure of carbon steel 30, after quenching, no residual
Austenite, and up to 30% of residual austenite is observed in the structure of U12 steel. Explain
The cause of this phenomenon. What kind of treatment can eliminate residual austenite?
5. Steel 45 was annealed at temperatures of 830 and 1000 ° C. Describe
Transformations occurring under these annealing regimes, indicate which ones are formed
Structure, and explain the reasons for obtaining different structures and properties. Give the definition
The annealing process and recommend the optimum heating temperature.