1. To study on the diagram "iron - cementite" the zones of steels heating for quenching. To study the diagrams of isothermal decomposition of austenite and cooling curves, which corresponds to various types of quenching.
2. To investigate influence of carbon quantity on hardness of quenched steel. The results of the test to note in the table. By the results of the experiment to draw the dependence graph of steel hardness on carbon quantity in quenched steel.
3. To make cooling of steel 45 in various cooling media. To measure hardness of gauges. Experiment data to note in the table. To draw the dependence graph of hardness on cooling rate.
4. To make quenching (in water) and tempering of gauges made of 45 steel at various temperatures. To measure hardness of gauges depending on tempering temperature. Experiment results to note in the table. To draw the dependence graph of hardness on tempering temperature.
Gauges number
Tempering temperature, °С
Tempering time, min
Hardness after quenching+tempering, НRС
Structure
name
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5. To study and to draw the microstructures of steels 30, 45 and У8 after various types of heat treatment.