Material Science

The atomic packing factor is the highest in which of the following cubic lattice system?

Raw material for all iron and steel product is ________.

Grey cast iron has ________.

18-4-1 high speed steel contains:

Essential gradient of any hardened steel is ________.

Thermodynamically stable defects

Beneficial property of foreign particles

Time dependent recoverable deformation under load is called

Decrease in free energy during recrystallization is attributed to

Phase formed of diffusion-less reaction:

Solve the following:

Solve the following:

Solve the following:

Solve the following:

Solve the following:

Solve the following:

Identify and draw all slip systems associated with FCC crystal. Calculate the tensile stress that is applied along the $[1 \bar{2} 0]$ axis of a gold crystal to cause slip on the $(1 \bar{1} \bar{1}) [0 \bar{1} 1]$ slip system, if the critical resolved shear stress is 10 MPa.

Write short notes on the following:

Which of the following is strong and ductile materials?

Which of the following statements is false?

Time-dependent permanent deformation is called

The most factor influencing diffusivity is

Which of the following is not a Hume-Ruthery condition?

Phase formed of diffusionless reaction is

Eutectoid product in Fe-C system is called

Failure due to excessive deformation is controlled by

Most often machine components are failed by

Last constituent to fail in fiber reinforced composites is

The accompanying figure shows the atomic packing schemes for several different crystallographic directions for a hypothetical metal. For each direction, the circles represent only the atoms contained within a unit cell, the circles are reduced from their actual size. Draw the unit cell and identify the crystal structure.

Show that a line of dislocation contains edge, screw or mixed dislocations.

For aluminium (atomic radius 0.1431 nm), compute the inter-planer spacing for (110) set of planes.

Calculate the atomic packing fraction for diamond cubic crystal and find its density (atomic radius $ r = 0.77 \text{ \AA} $).

Construct and label different regions of Ag-Cu phase diagram using the following data: Melting point of $ \text{Ag} = 960^\circ\text{C} $, Melting point of $ \text{Cu} = 1085^\circ\text{C} $, At eutectic point $ = 780^\circ\text{C} $, eutectic composition = 28 wt% Cu, maximum solubility of Ag in $ \text{Cu} = 8 \text{ wt%} $, maximum solubility of Cu in $ \text{Ag} = 6 \text{ wt%} $. At room temperature, maximum solubility of Ag in $ \text{Cu} = 3 \text{ wt%} $ and maximum solubility of Cu in $ \text{Ag} = 2 \text{ wt%} $. Assume the liquids, solidus and solvus line are straight. Calculate the amount of proeutectic phase in 60 wt% Cu alloy at $ 779^\circ\text{C} $ and draw the change in micro-structures when cooled slowly from liquid state to room temperature.

Construct isothermal transformation diagram for eutectoid steel, determine and draw the final microstructure of a small specimen that has been subjected to the following time-temperature treatment. In each case, assume that the specimen begins at $ 800^\circ\text{C} $, and that it has been held at this temperature long enough to have achieved a complete and homogeneous austenite structure:
(a) Rapidly cool to $ 250^\circ\text{C} $, hold for $ 10^5\text{ s} $, then quench to room temperature
(b) Rapidly cool to $ 400^\circ\text{C} $, hold for 10 s, then quench to room temperature
(c) Rapidly cool to $ 700^\circ\text{C} $, hold for $ 10^5\text{ s} $ then quench to room temperature
(d) Rapidly cool to $ 650^\circ\text{C} $ hold at this temperature for 6 s, rapidly cool to $ 400^\circ\text{C} $, hold for 10 s, then quench to room temperature

For a polymer-matrix fiber-reinforced composite-

list three functions of the matrix phase;

compare the desired mechanical characteristics of matrix and fiber phases;

cite two reasons why there must be a strong bond between fiber and matrix at their interface.

A continuous and aligned glass fiber-reinforced composite consists of 30 vol% of glass fibers having a modulus of elasticity of 69 GPa and 70 vol% of a polyester resin that, when hardened, displays a modulus of 3.4 GPa.

Compute the modulus of elasticity of this composite in the longitudinal direction.

If the cross-sectional area is $ 250 \text{ mm}^2 $ and a stress of 40 MPa is applied in this longitudinal direction, compute the magnitude of the load carried by each of the fiber and matrix phases.

Determine the strain that is sustained by each phase when the stress in part (b) is applied.

What is cast iron? How does it differ from pig iron?

Compare ductile (nodular) cast iron with other cast iron on the basis of mechanical properties, composition and microstructure.

(a) Composite and alloys

(b) Annealing and normalizing

(c) Cross-slip and jog

(d) Frank-Read source

Which of the following is strong and ductile materials?

Which of the following statements is false?

Time-dependent permanent deformation is called

The most factor influencing diffusivity is

Which of the following is not a Hume-Ruthery condition?

Phase formed of diffusionless reaction is

Eutectoid product in Fe-C system is called

Failure due to excessive deformation is controlled by

Most often machine components are failed by

Last constituent to fail in fiber reinforced composites is

The accompanying figure shows the atomic packing schemes for several different crystallographic directions for a hypothetical metal. For each direction, the circles represent only the atoms contained within a unit cell, the circles are reduced from their actual size. Draw the unit cell and identify the crystal structure.

Show that a line of dislocation contains edge, screw or mixed dislocations.

For aluminium (atomic radius 0.1431 nm), compute the inter-planer spacing for (110) set of planes.

Calculate the atomic packing fraction for diamond cubic crystal and find its density (atomic radius $ r = 0.77 \text{ \AA} $).

Construct and label different regions of Ag-Cu phase diagram using the following data: Melting point of $ \text{Ag} = 960^\circ\text{C} $, Melting point of $ \text{Cu} = 1085^\circ\text{C} $, At eutectic point $ = 780^\circ\text{C} $, eutectic composition = 28 wt% Cu, maximum solubility of Ag in $ \text{Cu} = 8 \text{ wt%} $, maximum solubility of Cu in $ \text{Ag} = 6 \text{ wt%} $. At room temperature, maximum solubility of Ag in $ \text{Cu} = 3 \text{ wt%} $ and maximum solubility of Cu in $ \text{Ag} = 2 \text{ wt%} $. Assume the liquids, solidus and solvus line are straight. Calculate the amount of proeutectic phase in 60 wt% Cu alloy at $ 779^\circ\text{C} $ and draw the change in micro-structures when cooled slowly from liquid state to room temperature.

Construct isothermal transformation diagram for eutectoid steel, determine and draw the final microstructure of a small specimen that has been subjected to the following time-temperature treatment. In each case, assume that the specimen begins at $ 800^\circ\text{C} $, and that it has been held at this temperature long enough to have achieved a complete and homogeneous austenite structure:
(a) Rapidly cool to $ 250^\circ\text{C} $, hold for $ 10^5\text{ s} $, then quench to room temperature
(b) Rapidly cool to $ 400^\circ\text{C} $, hold for 10 s, then quench to room temperature
(c) Rapidly cool to $ 700^\circ\text{C} $, hold for $ 10^5\text{ s} $ then quench to room temperature
(d) Rapidly cool to $ 650^\circ\text{C} $ hold at this temperature for 6 s, rapidly cool to $ 400^\circ\text{C} $, hold for 10 s, then quench to room temperature

For a polymer-matrix fiber-reinforced composite-

list three functions of the matrix phase;

compare the desired mechanical characteristics of matrix and fiber phases;

cite two reasons why there must be a strong bond between fiber and matrix at their interface.

A continuous and aligned glass fiber-reinforced composite consists of 30 vol% of glass fibers having a modulus of elasticity of 69 GPa and 70 vol% of a polyester resin that, when hardened, displays a modulus of 3.4 GPa.

Compute the modulus of elasticity of this composite in the longitudinal direction.

If the cross-sectional area is $ 250 \text{ mm}^2 $ and a stress of 40 MPa is applied in this longitudinal direction, compute the magnitude of the load carried by each of the fiber and matrix phases.

Determine the strain that is sustained by each phase when the stress in part (b) is applied.

What is cast iron? How does it differ from pig iron?

Compare ductile (nodular) cast iron with other cast iron on the basis of mechanical properties, composition and microstructure.

(a) Composite and alloys

(b) Annealing and normalizing

(c) Cross-slip and jog

(d) Frank-Read source

Which of the following materials is the hardest?

The phase boundary between $ \alpha $ and $ (\alpha + \beta) $ regions is called

The interstitial solid solution of carbon in $ \gamma $-iron is called

For a spherical particle of radius r, the volume to surface area ratio is

Which of the following refers to eutectoid reaction?

If one solid phase splits into two solid phases on heating, the reaction is

Cast iron normally contains

Piezo-electric materials produce electric field when subjected to

Examples of ferrous metals are

In a single-component system, the maximum no. of phases that can co-exist in equilibrium, is

State and explain the equation for Gibbs phase rule.

Derive the lever rule for the amount in wt. percent of each phase in two phase regions of a binary phase diagram.

What is a hybrid composite?

Write the important advantages of hybrid composites over normal fiber composites.

Find an expression for the modulus of elasticity for a hybrid composite in which all fibers of both types are oriented in the same direction.

Explain with reason why glass fiber reinforced composites are utilized extensively.

Explain the limitations of glass fiber reinforced composites.

Compare gray and malleable cast iron with respect to:

(a) composition and heat treatment;

(b) microstructure;

(c) mechanical characteristics.

What is the distinction between cement and concrete?

Write some important limitations that restrict the use of concrete as structural material.

Explain the techniques that are utilized to strengthen concrete by reinforcement.

Classify different types of materials with their properties and application.

Write short notes on the following: (i) Biomaterial (ii) Optical fiber (iii) Nanomaterials

Draw the lead-tin phase diagram.

What are the compositions of phases?

Calculate the relative amount of each phase present in terms of mass fraction.

(a) Bainite

(b) White cast iron

(c) Martensite

(d) Hume-Rothery Rules

Which of the following materials is the hardest?

The phase boundary between $ \alpha $ and $ (\alpha + \beta) $ regions is called

The interstitial solid solution of carbon in $ \gamma $-iron is called

For a spherical particle of radius r, the volume to surface area ratio is

Which of the following refers to eutectoid reaction?

If one solid phase splits into two solid phases on heating, the reaction is

Cast iron normally contains

Piezo-electric materials produce electric field when subjected to

Examples of ferrous metals are

In a single-component system, the maximum no. of phases that can co-exist in equilibrium, is

State and explain the equation for Gibbs phase rule.

Derive the lever rule for the amount in wt. percent of each phase in two phase regions of a binary phase diagram.

What is a hybrid composite?

Write the important advantages of hybrid composites over normal fiber composites.

Find an expression for the modulus of elasticity for a hybrid composite in which all fibers of both types are oriented in the same direction.

Explain with reason why glass fiber reinforced composites are utilized extensively.

Explain the limitations of glass fiber reinforced composites.

Compare gray and malleable cast iron with respect to:

(a) composition and heat treatment;

(b) microstructure;

(c) mechanical characteristics.

What is the distinction between cement and concrete?

Write some important limitations that restrict the use of concrete as structural material.

Explain the techniques that are utilized to strengthen concrete by reinforcement.

Classify different types of materials with their properties and application.

Write short notes on the following: (i) Biomaterial (ii) Optical fiber (iii) Nanomaterials

Draw the lead-tin phase diagram.

What are the compositions of phases?

Calculate the relative amount of each phase present in terms of mass fraction.

(a) Bainite

(b) White cast iron

(c) Martensite

(d) Hume-Rothery Rules

Which is closest to the purest form of iron?

The process of isothermal transformation to form bainite in steel, is known as

Which of the following is not a permanent magnetic material?

Which one of the following materials is viscoelastic in nature?

If the structure of a sample consists of pearlite, cementite and free carbon, the sample may be

Pearlite is obtained when steel is

A material having different properties in different directions, is known as

Temperating of hardened steel is done to increase its

The fatigue strength of materials increases

The capacity of a metal to exhibit considerable elastic recovery upon release, is known as

Give the classification of ceramic materials, organic materials, electrical materials and magnetic materials with their properties and applications.

Write short notes on: (i) Nanomaterials (ii) Biomaterials (iii) Optical fibre

What is a 'phase diagram'? How is it classified? What useful information does it provide?

State Gibbs' phase rule. What is the minimum and maximum number of phases which could exist in a pure metal?

Discuss the Hume-Rothery rules for alloy formation.

Draw the iron-carbon phase diagram and discuss briefly the structure and properties of steel having 0.83% and 0.40% carbon when cooled from $ 1000^\circ\text{C} $ to room temperature.

Draw a TTT diagram of eutectoid steel. Discuss all the transformation with the rate of cooling.

Why continuous cooling of plain carbon steel does not show bainite in its microstructure?

What effect does a change in heating or cooling rate have upon the transformation temperature in steel?

Calculate the thickness of micro-constituents present in pearlite if density of ferrite and cementite is $ 7.76 \text{ gm/cc} $ and $ 7.66 \text{ gm/cc} $ respectively.

A steel contains 40% ferrite and 60% pearlite at room temperature. Determine the amount of total ferrite and cementite present in the alloy.

What are the various types of annealing? Where are they used?

What is the major difference in the purpose of annealing and normalizing?

"Hardening of steel is always followed by tempering." Is it true or false? If true, give reasons.

What are the different types of composite materials available? Give their suitable examples with applications.

What are the most important rules for designing composite parts?

Write the applications of cemented carbide composite.

(a) Plain carbon steel and Alloy steel

(b) White cast iron and Malleable cast iron

(c) Grey cast iron and Spheroidal grey iron

(d) Eutectics and Eutectoids

Which is closest to the purest form of iron?

The process of isothermal transformation to form bainite in steel, is known as

Which of the following is not a permanent magnetic material?

Which one of the following materials is viscoelastic in nature?

If the structure of a sample consists of pearlite, cementite and free carbon, the sample may be

Pearlite is obtained when steel is

A material having different properties in different directions, is known as

Temperating of hardened steel is done to increase its

The fatigue strength of materials increases

The capacity of a metal to exhibit considerable elastic recovery upon release, is known as

Give the classification of ceramic materials, organic materials, electrical materials and magnetic materials with their properties and applications.

Write short notes on: (i) Nanomaterials (ii) Biomaterials (iii) Optical fibre

What is a 'phase diagram'? How is it classified? What useful information does it provide?

State Gibbs' phase rule. What is the minimum and maximum number of phases which could exist in a pure metal?

Discuss the Hume-Rothery rules for alloy formation.

Draw the iron-carbon phase diagram and discuss briefly the structure and properties of steel having 0.83% and 0.40% carbon when cooled from $ 1000^\circ\text{C} $ to room temperature.

Draw a TTT diagram of eutectoid steel. Discuss all the transformation with the rate of cooling.

Why continuous cooling of plain carbon steel does not show bainite in its microstructure?

What effect does a change in heating or cooling rate have upon the transformation temperature in steel?

Calculate the thickness of micro-constituents present in pearlite if density of ferrite and cementite is $ 7.76 \text{ gm/cc} $ and $ 7.66 \text{ gm/cc} $ respectively.

A steel contains 40% ferrite and 60% pearlite at room temperature. Determine the amount of total ferrite and cementite present in the alloy.

What are the various types of annealing? Where are they used?

What is the major difference in the purpose of annealing and normalizing?

"Hardening of steel is always followed by tempering." Is it true or false? If true, give reasons.

What are the different types of composite materials available? Give their suitable examples with applications.

What are the most important rules for designing composite parts?

Write the applications of cemented carbide composite.

(a) Plain carbon steel and Alloy steel

(b) White cast iron and Malleable cast iron

(c) Grey cast iron and Spheroidal grey iron

(d) Eutectics and Eutectoids

The cupola is used to make

Iron has the unique characteristic of being

Monel metal is an alloy of ________ and ________.

Cermets are

Nanocomposite materials are highly preferable in design considerations for their

The steel products which are required to be shock resistant should have

Which of the following structures has maximum hardness?

An iron-carbon binary alloy has 0.5% carbon by weight. What is this alloy called?

As per Gibbs' phase rule, if the number of components is equal to 2, then the number of phases will be

Tempering temperature of most of the materials is of the order of

Whiskers

Glass fibre-reinforced polymer composite

Tempered martensite

Hume-Rothery rule