Metallurgy And Material Science -jan2003-nr-220302

Set No. Code No.220302 II-B.Tech. II-Semester Supplementary Examination January - 2003

1

METALLURGY AND MATERIAL SCIENCE (Common to Mechanical Engineering, Production Engineering, Mechatronics and Mechanical Manufacturing Engineering) Time:3 hours Max.Marks:80 Answer any FIVE questions All questions carry equal Marks --1.a) Calculate the packing efficiency of a BCC structure. b) What are the attractive properties of materials having covalent bonds? c) Explain with neat sketches the different types of crystal structures. 2.a) b) c) 3.a) b) c)

Critically compare the solidification of a pure metal and a solid solution. How are equilibrium diagrams constructed using cooling curves? Explain in detail with relevant diagrams. State the phase rule. How are the grain boundaries formed in a crystal. Calculate the amount of micro-constituents (ferrite, pearlite and cementite) present in a 0.5% carbon steel and a 1.2% carbon steel at room temperature after slow cooling. Compare the properties of plain carbon steels with those of alloy steels.

4.a) b)

Draw the Copper-Nickel equilibrium diagram and label the diagram. Briefly discuss the microstructures and properties of gray castiron.

5.a) b) c)

How is the TTT diagram for an eutectoid steel determined experimentally. State the usefulness of TTT diagram in heat treatment of steels. How is aluminum alloys strengthened by age hardening process?

6.a)

Hardening is always followed by tempering process. Why? Describe the various tempering processes used in heat treatment. Discuss any Two of the following: i) Nickel base alloys (ii) Bearing alloys (iii) Titanium alloys.

b) 7.a) b) c)

What are the outstanding properties of ceramic materials. Write the properties and engineering applications of glasses. How are the composite materials manufactured?

8.

Distinguish the following: a) Solid solution and intermetalic compounds (b) Eutectic and peritectic system (c) Equilibrium and non-equilibrium solidification of metals. *** *** ***

Code No.220302 II-B.Tech. II-Semester Supplementary Examination January – 2003

Set No.

2

METALLURGY AND MATERIAL SCIENCE (Common to Mechanical Engineering, Production Engineering, Mechatronics and Mechanical Manufacturing Engineering) Time:3 hours Max.Marks:80 Answer any FIVE questions All questions carry equal Marks --1.a) Define the relationship between the atom size and cell dimension for a FCC structure. b) What is meant by Miller indices? Give the importance of the Miller indices. Calculate the Miller indices of a plane that intersects the X axis at 2 and the Y axis at ½ and is parallel to the Z axis. The structure is cube. c) What are the imperfections found in metal crystals? What is the role of these imperfections on the properties of a metal? 2.a) b) c) 3.a) b) c)

Briefly explain the significance of nucleation and growth. What is an alloy? What is the need for alloying? Mention the important properties, which are obtained by alloying. What is meant by intermetallic compound? Explain briefly the different types of intermatallic compounds. Explain the eutectic and peritectic reactions with suitable examples. Explain the effects of Carbon, Silicon, Manganese and Sulfur on the properties of plain carbon steel. Describe the classification of steel.

4.a) b)

What are the types of castiron and describe them with help of microstructures. Draw an isothermal transformation diagram of a hypoeutectic steel and indicate the influence of cooling rate on the microstructures formed.

5.a) b)

Discuss the microstructure of martensite with a neat sketch. What are the important engineering properties those non-ferrous metals posses, which are not available with ferrous metals?

6.a) b) c)

Discuss the different types of carburising processes. What are the some outstanding properties of ceramic materials? Describe two important ceramic materials used in engineering applications.

7.a)

What is a composite material? How are their properties affected by their basic structures? (contd…2)

Code No.220302 b) c) 8.

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Set No.2

Name the properties of composite materials, which are making them more attractive for engineering applications. Explain briefly the matrix in a fibre-reinforced composite. Write short notes on any THREE of the following: a) Die steels b) Tool steels c) Soldering alloys d) Bearing alloys. ***

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Set No.

3

Code No.220302 II-B.Tech. II-Semester Supplementary Examination January - 2003

METALLURGY AND MATERIAL SCIENCE (Common to Mechanical Engineering, Production Engineering, Mechatronics and Mechanical Manufacturing Engineering) Time:3 hours Max.Marks:80 Answer any FIVE questions All questions carry equal Marks --1.a) b) c)

Differentiate between crystal, dendrite and grain. Explain with neat sketches the different types of crystal structures. Explain why a covalent bond is directional while ionic and metallic bonds are non-directional.

2.a) b) c)

What are the important crystal defects and explain one of them in detail. Explain the different types of solid solutions with suitable examples. Draw the phase diagram for an isomorphose alloy and describe its salient features.

3.a) b)

Draw iron-carbon equilibrium diagram and label all phases. Using iron-carbon equilibrium diagram explain the following reactions: i) Eutectic (ii) Eutectoid and (iii) Peritectoid. Give the typical compositions, properties and applications of tool steels.

c) 4.a)

b)

Outline the principles underlying the surface hardening of steels by methods which involve i) Changes in both the composition and structure of the surface relative to the main body of the component. ii) Changes in structure of the surface layer only, the composition remaining constant throughout. Describe about compositions, properties and applications of any two copper alloys.

5.a) b) c)

Write down the steps to obtain the isothermal transformation diagram. Describe the flame hardening process. What are the various ceramic materials used as cutting tool materials. Name the properties, which make them suitable for using them as cutting tool materials.

6.a) b) c)

Explain the three primary geometries of the composite materials. Discuss the role of matrix in a fibre-reinforced composite. Name the major limitations of composite materials in engineering applications. (contd…2)

Code No.220302

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Set No.3

7.

Write short notes on any THREE of the following: a) Abrasive materials b) Electron compounds c) White castiron d) Metal-matrix composites.

8.

Differentiate the following: a) Annealing and Normalising b) Work hardening and Age Hardening c) Carburising and Cyaniding. ***

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Set No. Code No.220302 II-B.Tech. II-Semester Supplementary Examination January - 2003

4

METALLURGY AND MATERIAL SCIENCE (Common to Mechanical Engineering, Production Engineering, Mechatronics and Mechanical Manufacturing Engineering) Time:3 hours Max.Marks:80 Answer any FIVE questions All questions carry equal Marks --1.a) b) c)

What you understand by the term space lattice. How many types are found in metals? What is a unit cell? Name the different types of crystal systems and explain any one with neat sketches. Sketch the planes and directions of the following in a cubic system (111); (112); [110]; [101].

2.a) b) c)

Differentiate between ionic, covalent and metallic bonds. Name the important defects found in the crystals and explain any one in detail. Define Burger’s vector and illustrate it on an edge dislocation.

3.a) b)

Discuss non-equilibrium cooling with examples. Write the effects of the addition of Manganese, Silicon, Sulfur and Phosphorus on steel. What is meant by martensite? What is its significance?

c) 4.a) b) c) 5.a) b) 6.a) b) c)

Explain effect of tempering process on mechanical properties of steel. Describe the Jominy’s end quench test used for measuring the hardenability of steel. Differentiate the surface hardening process with full hardening process. Draw a continuous cooling diagram and explain the effect of cooling rate on the formation of pearlite, bainite and martensite. Discuss about the manufacturing and applications of spheroidal graphite iron. Describe the composition, properties and applications of duralumin. Name the ceramics used as cutting materials and mention the properties, which make them suitable to use as cutting tool materials. Name the copper alloys and list their applications.

(contd…2)

Code No.220302 7.a) b) c)

8.

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Set No.4

List the various engineering applications of refractory materials. Name the four basic types of fibre reinforced composites. Describe any one of them in detail. What are the advantages of using composite materials for engineering applications? Write short notes on any THREE of the following: a) Carburising b) Age hardening c) High speed steels d) Reinforced composites. ***

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