Complete answers to 4 questions of 36 variants of the 2 control work on materials science by the method of Garbuzovoy NE are given.
1. Assign a quenching temperature, cooling medium, tempering temperature for various devices of steel 45, which must have a hardness of 28-35HRC. Describe the microstructure and properties of the steel after heat treatment.
2. Steel 4ХВС is chosen for manufacturing of embanking and stamping dies. Specify the composition and determine the steel group for the purpose. Assign a mode of heat treatment, give its justification, explaining the effect of doping on the transformation during the heat treatment of this steel. Describe the structure and properties of stamps after thermal treatment.
3. For parts operating in weak corrosive environments, steel 20X13 is used. Specify the composition and explain the reason for introducing chromium into this steel. Assign and justify the heat treatment and describe the microstructure after treatment.
4. For the manufacture of critical parts (bushings, valves, gear wheels, etc.), the alloy BRAZHN10-4-4 is chosen. Decipher the composition, specify the mode of heat treatment, mechanical properties and describe the structure using the copper-aluminum state diagram.
No feedback yet