Option 15
1. What are the main factors that determine the grain size of the crystallized metal and
why?
2. What kind of plastic deformation (cold or hot) is
Deformation of iron at a temperature of 500 ° C? Explain how this changes the structure
And the properties of iron.
3. Draw a diagram of the iron-iron carbide state, 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 1.9% C. What is the structure of this
Alloy at room temperature and how such an alloy is called?
4. Using a state diagram, iron-cementite and a graph of hardness versus
Tempering temperature, assign a heat treatment mode (tempering temperature,
Cooling medium and tempering temperature) of various devices of steel 45, which
Should have a hardness of 28 ... 30 HRC. Describe the transformations occurring at all stages
Heat treatment, the resulting structure.
5. Draw a diagram of the isothermal transformation of austenite for steel V8, apply
On it curves curves of normal hardening, stepwise and isothermal. What are the advantages and
The shortcomings of each of these types of hardening?