Dislocation cross-slip is difficult in those materials, which have
Large number of slip systems
High work hardening rate
Coarse grain size
Low stacking fault energy
Correct Answer :
D. Low stacking fault energy
Related Questions
Air-petrol ratio in an automotive petrol engine is around
14 : 1
22 : 1
25 : 1
4 : 1
Which of the following is used to produce draught in the locomotive boilers?
Chimney
Induced draught fan
Forced draught fan
Steam jet arrangement
Drossing is a __________ operation.
Smelting
Dressing
Roasting
Dressing
Ferromagnetic materials owe their properties to __________ inner sub-shells.
Completely filled
Partially filled
Equally filled
Vacant
In extrusion of metals, which of the following statement is true?
Speed of the extruded material is same as that of ram speed
Redundant work is a function of the die angle
Relative motion between the billet surface and the container wall is always present
Hollow ram is used for indirect extrusion
Which of the following parameters is not responsible for the heat loss from a hot steam carrying bare pipe surface located in a room without fans?
Emissivity of pipe surface
Diameter & length of the pipe
Temperature of hot pipe surface & that of air in the room
None of these
Steel rods are normally used for concrete reinforcement because concrete and steel have almost equal
Tensile strength
Compressive strength
Young's modulus
Thermal co-efficient of expansion
A material is capable of resisting softening at high temperature, because of its property termed as
Hot temper
Hot hardness
Fatigue
Creep
Runge-Kutta method is used to solve a/an
Ordinary differential equation of nth order
Simultaneous non-linear equation
Linear differential equation
None of these
Air intake for an air compressor should be preferably taken from
A site, where cooling towers are located nearby
A site, where open coal yard in located nearby
An air conditioned room maintained at a temperature of 18°C
An outside atmosphere at 10°C
Main constituent of bone ash is
Ammonium phosphate
Calcium phosphate
Animal charcoal
Ammonium sulphate
Moist air is cooled along the line of constant __________ , when it is passed over a cold & dry cooling coil, such that no condensation occurs?
Enthalpy
Relative humidity
Wet bulb temperature
Dew point temperature
The __________ of a double acting reciprocating pump as compared to the single acting pump will be almost double.
Flow output
Head developed
Overall efficiency
Weight
The elastic strain energy of a unit length of an edge dislocation as compared to that of a screw dislocation is
More
Equal
Less
Double
Titanium is added to molten aluminium alloys before casting for the purpose of
Grain refinement
Increasing corrosion resistance
Reducing porosity
Improving fluidity
Which of the following materials has the poorest electrical conductivity?
Carbon
Aluminium
Silver
Stainless steel
Percentage of argon (by volume) in dry atmospheric air is about
0.09
0.3
0.57
0.94
Fog is an example of colloidal system of
Solid dispersed in gas
Solid dispersed in liquid
Liquid dispersed in gas
Gas dispersed in liquid
Which of the following alloying elements is present in maximum percentage in high speed steel?
Molybdenum
Chromium
Tungsten
Vanadium
The starting of a car takes time in winter, because the
Octane number of fuel is decreased
Fuel supply for ignition is not sufficient
Vaporisation of the fuel is decreased
Pour point of fuel decreases
Viscoelastic behaviour is observed in __________ materials.
Non-crystalline organic polymeric
Ceramic
All crystalline
All amorphous
Capacity & power requirement for an air compressor working at high altitude compared to sealevel will be
More
Less
Same
Either more or less; depends on the climatic conditions
Even though heat transfer co-efficient in boiling liquids is large, use of fins is advantageous, when the entire surface is exposed to __________ boiling.
Film
Nucleate
Transition
All modes of
Pick out the wrong statement.
Weldability of high carbon steel is poorer compared to low carbon steel
Invar is a magnetic alloy
Magnetic permeability of the diamagnetic material is less than one
Martenistic transformation never goes to completion (i.e., 100%) at room temperature
If a nuclear reactor produces more fissile nuclear fuel than it consumes, then it is called a __________ reactor.
Critical
Breeder
Fertile
Heterogeneous
The stress at which extension of the material takes place more rapidly as compared to the increase in load is termed as the __________ point of the material.
Elastic
Ultimate
Yielding
Breaking
The trace metal present in insulin is
Cu
Zn
Fe
Ni
Cold cracking in the heat affected zone of a high strength steel weld can take place because of the
Retained austenite
Martensite formation
Relatively high sulphur content in the base metal
Sufficient hydrogen present in the welding arc
Tin based white metals are used, where bearings are subjected to
High pressure & load
Low pressure & load
High temperature
Large surface wear
Heating of ferromagnetic materials to a temperature above Curie temperature makes it
Insulator for heat & electricity transmission
Ferritic
Behave like paramagnetic materials
Superconductor