Materials science

TOOLS AND MATERIALS
To perform the work, you need: a metallographic microscope, a collection of microslides of structural steel, a circle and a ruler.
Order of work
Observation and study of the microstructure of structural steel under a metallographic microscope at magnifications of 200 to 500 times.
Draw a picture of the microstructure in a circle with a diameter of about 60 mm or a square with a size of 60x60 mm.
CONTROL QUESTIONS

1. 
   What kind of steel is called structural steel? What types is it divided into?
   
2. 
   What kind of steel is called carbon structural steel?
   
3. 
   What steels are called alloy structural steels?
   
4. 
   What kind of steel is called spring steel?
   
5. 
   What kind of steel is called ball-bearing steel?
   

REPORT WRITING PROCEDURE.

1. 
   Purpose of work.
   
2. 
   Brief theoretical information.
   
3. 
   Assignment.
   
4. 
   Pictures of microstructures with explanatory letters.
   
5. 
   List of references.
   

8-LABORATORY WORK
SUBJECT OF TRAINING: MICROANALYSIS OF TOOL STEEL


PURPOSE OF THE WORK: Independent microanalysis of tool steels and study of their composition depending on the appearance of the structure.


BRIEF THEORETICAL INFORMATION

Tool steels are carbon and alloy steels containing more than 0.7% carbon.

These steels are very hard, durable and corrosion resistant and are used for making various tools. Usually such steels are post-eutectoid or ledeburite steels obtained after quenching and tempering. The structure consists of martensite and excess carbide. Such steels are very hard (NRS60-65) and have low viscosity.
One of the main characteristics of tool steels is their heat resistance, that is, their resistance (or resistance) to loosening due to the heating of the tool during use.
The working conditions of the measuring tool are close to the working conditions of cutting tools in light mode. The difference is that much less pressure is applied to the treated surface.
Steel is subjected to considerable heat and impact during stamping. This effect is distributed over a much larger area.
The viscosity of steel plays an important role in this process.
The quality of such steels are the best stamping steels when the hardness and viscosities of the steel are the best in the working conditions at the temperature suitable for stamping.
Carbon and alloy steels are used for light-duty cutting tools and measuring tools. High-speed steels are used for cutting tools that work in an enhanced mode.