Material Science Control 2 Option 12 by Garbuzov

Complete answers to 5 questions of 12 variants of the 2 control work on materials science by the methodology of Garbuzova N.Ye. are given.
1. Select carbon steel for making files. Assign a heat treatment mode, describe the essence of the occurring transformations, the structure and properties of the tool after Thermal processing.
2. As a result of heat treatment, the springs should receive high elasticity. To make them, steel 50ХГФА was chosen. Specify the composition, designate, and justify the thermal treatment regime, explaining the effect of doping on the transformations occurring during the heat treatment of this steel. Describe the structure and properties of springs after heat treatment.
3. For parts operating in an oxidizing atmosphere, steel 12X13 is used. Specify the composition and determine the class of steel by structure. Explain the purpose of chromium in this steel and justify the choice of steel grade for these working conditions.
4. AK4 alloy is selected for the manufacture of certain parts of internal combustion engines. Decipher the composition, specify the method of manufacture of parts from this alloy and give the characteristics of the mechanical properties of the alloy at elevated temperatures.
5. Physical principles of welding of plastics. Describe the methods of welding with direct heating.