Untitled Presentation

Open Ended

Explain how heat treatment can improve the properties of raw steel, using information from the images and text.

Multiple Choice

Why is the production of crude steel important for modern society?

• It is essential for building infrastructure and manufacturing goods.

• It is only used for making jewelry.

• It has no impact on technological development.

• It is mainly used for decorative purposes.

Open Ended

What is the significance of the process called 'skujňovanie' in steel production?

Open Ended

Explain how the reduction of unwanted elements in raw iron affects the mechanical and technological properties of steel.

Multiple Choice

What is the main goal of the steelmaking process as described in the first image?

• To increase the content of C, Si, Mg, P, and S in raw iron

• To reduce the content of C, Si, Mg, P, and S in raw iron to prescribed values

• To add more impurities to the steel

• To melt steel for casting

Multiple Choice

Which of the following statements about Siemens-Martinské pece is correct?

• They use waste heat to preheat the heating gas and air, enabling temperatures above 1600°C.

• They were invented in 1784.

• They use only direct heating methods.

• They cannot reach temperatures above 1200°C.

Multiple Select

Select all correct statements about electric arc furnaces (EOP) as shown in the last image:

• They can use direct heating.

• They can use indirect heating.

• They can use combined heating (electroslag remelting).

• They only use gas as a heating source.

Multiple Choice

Which of the following is NOT a characteristic or purpose of electric arc furnaces (EOP)?

• Production of 20% of the world's steel, mostly special steels

• High efficiency and product purity

• Capacity of 200 tons with O2 intensification

• Production of aluminum alloys

Multiple Select

Which of the following are types of input materials used in electric arc furnaces (EOP)?

• Iron ore pellets

• Scrap steel free of rust

• Oxidizing additives (e.g., Fe oxides, agglomerates, gaseous O2)

• Plastic waste

Open Ended

Compare the technological steps involved in processing carbon-containing raw materials and alloyed raw materials in electric arc furnaces. What is the main difference between the two processes?

Multiple Choice

What is the main function of the electric arc in an electric arc furnace?

• To cool the furnace

• To melt steel scrap

• To remove slag

• To add alloying elements

Multiple Choice

How is the metal heated in electric induction furnaces?

• By burning fuel

• By electromagnetic induction

• By chemical reaction

• By resistance heating

Multiple Choice

What is the main purpose of blowing oxygen into the LD converter during steel production?

• To remove impurities from pig iron

• To cool down the converter

• To add carbon to the steel

• To solidify the molten steel

Multiple Select

Which of the following are technological additives used in the LD converter process?

• Deoxidants

• Slag-forming additives

• Water

• Plasticizers

Open Ended

Describe the sequence of steps involved in the production process using the LD converter, based on the provided images and text.

Multiple Choice

Which property is NOT listed as a basic property of raw steel?

• High strength

• High ductility

• Low corrosion resistance

• Good workability

Multiple Choice

Which alloy of iron is considered the most important for technical use, and why is it necessary to understand its equilibrium diagram?

• Steel, because it is the most widely used alloy and its properties depend on the Fe-C equilibrium diagram.

• Cast iron, because it is used for making pipes and machinery.

• Bronze, because it is corrosion-resistant.

• Brass, because it is easy to machine.

Multiple Select

Select all the correct statements about the significant temperatures in the heat treatment of steel.

• At 768°C, iron loses its magnetism.

• At 909°C, the atomic lattice changes from 9 to 14 atoms.

• At 1401°C, the atomic lattice changes from 14 to 9 atoms.

• At 1535°C, iron melts.

Multiple Choice

Which of the following temperatures is associated with the loss of magnetism in iron during heating?

• 768°C

• 909°C

• 1401°C

• 1535°C

Open Ended

Describe the changes that occur in the structure and properties of iron as it is heated through the critical temperatures shown in the equilibrium diagram.

Open Ended

How would you summarize the importance of removing metallic and non-metallic impurities during the steelmaking process?

Multiple Choice

What is the process called by which raw iron is converted into crude steel in steelworks?

• Refining

• Alloying

• Tempering

• Skujňovanie