JNTU IV B.Tech I Semester Supplimentary Examinations, February 2008
(Metallurgy & Material Technology)
1. (a) What is Sievert’s law? Does it apply for Basic Bessemer process? If so, how?
(b) What modifications need to be done to reduce nitrogen-content in Basic Bessemer steels?
(c) What are advantages and disadvantages of having a high nitrogen content in steels.
2. (a) Explain the Rotor Oxygen process of steel making with a neat sketch of rotor furnace.
(b) What are the reactions taking place in the rotor-process of steel making?
3. (a) What are the different reactions taking place at slag-metal interface? How can these reactions made faster?
(b) Where does the Carbon-Oxygen reaction take place in a Bessemer process?
Does it take place at slag-metal interface? Explain?
4. (a) What are the essential conditions for desulphurisation to take place? Explain with the help of ’S’ – removal reaction?
(b) Explain the difference between acid -processes and basic electric process with respect to desulphurisation?
5. (a) When is a open-hearth practice considered a hot-metal practice?
(b) What practice needs to be followed to minimise scrap consumption in open hearths not provided with slag flushing facilities.
6. (a) What are the different types of electric arc furnaces? What is the principle of each?
(b) Which type of arc furnace is preferred for non-ferrous and which one for ferrous alloy production?
(c) Why basic electric arc process is preferred over acid electric arc processes?
7. (a) Describe the development of secondary steel making processes through the years?
(b) Explain the difference between primary steel making and secondary steel making?
8. (a) Explain the principle of continuous casting in detail.
(b) List out the equipment needed for continuous – casting of steel.
(c) Draw a neat sketch of continuous casting-machine and mention the parts.