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It CORRESPONDS to maximum HEAT flux at which TRANSITION OCCURS from NUCLEATE boiling to film boiling.

It corresponds to maximum heat flux at which transition occurs from nucleate boiling to film boiling.

It is an automatic machine in which WORKPIECE alongwith fixture is transferred from one STATION to other automatically and SEVERAL OPERATION on workpiece are performed at each station.

It is an automatic machine in which workpiece alongwith fixture is transferred from one station to other automatically and several operation on workpiece are performed at each station.

It is USED to MEASURE the total hemispherical solar RADIATION.

It is used to measure the total hemispherical solar radiation.

A basic HOLE is ONE WHOSE LOWER DEVIATION is zero and in case of basic shaft the upper deviation is zero.

A basic hole is one whose lower deviation is zero and in case of basic shaft the upper deviation is zero.

Modulus of resilience is the MAXIMUM strain energy STORED in a material per unit volume and modulus of rigidity is the RATIO of SHEARING stress to the shearing strain within the elastic limit.

Modulus of resilience is the maximum strain energy stored in a material per unit volume and modulus of rigidity is the ratio of shearing stress to the shearing strain within the elastic limit.

It is a MATERIAL having same ELASTIC CONSTANTS in all DIRECTIONS.

It is a material having same elastic constants in all directions.

A conjugate beam is an imaginary beam of same size as original beam and carrying a distributed load in ACCORDANCE with the bending moment DIAGRAM.

A CONTINUOUS beam is one which is RESTING on more than two SUPPORTS.

A conjugate beam is an imaginary beam of same size as original beam and carrying a distributed load in accordance with the bending moment diagram.

A continuous beam is one which is resting on more than two supports.

It is the PROCESS of IMPROVING fatigue properties by first under-stressing and then INCREASING the stress in small INCREMENTS.

It is the process of improving fatigue properties by first under-stressing and then increasing the stress in small increments.

A CABLE ATTACHED to the SUPPORTS and CARRYING its own WEIGHT.

A cable attached to the supports and carrying its own weight.

It is the ratio of the EQUIVALENT length of COLUMN to the MINIMUM radius of GYRATION.

It is the ratio of the equivalent length of column to the minimum radius of gyration.

Manganese is an excellent deoxidizer and sulfur neutralizer, and improves the mechanical properties of steel, notably the ratio of yield strength to tensile strength at NORMAL temperatures. As an alloying ELEMENT, manganese serves as an inexpensive means of preventing "hot shortness". It improves rolling properties, hardenability, and resistance to wear. However manganese increases the CRACK sensitivity of weldments, PARTICULARLY with steels of higher carbon content.

Manganese is an excellent deoxidizer and sulfur neutralizer, and improves the mechanical properties of steel, notably the ratio of yield strength to tensile strength at normal temperatures. As an alloying element, manganese serves as an inexpensive means of preventing "hot shortness". It improves rolling properties, hardenability, and resistance to wear. However manganese increases the crack sensitivity of weldments, particularly with steels of higher carbon content.

Silicon contributes greatly to the production of sound steel because of its deoxidizing and degasifying properties. When ADDED in amounts up to 2.5%, the ultimate strength of the steel is increased without LOSS in ductility. Silicon in EXCESS of 2.5% causes brittleness, and amounts higher than 5% MAKE the steel non-malleable.

Resistance to oxidation and surface stability of steel are increased by the addition of silicon. These desirable effects partially compensate for the tendency of silicon to lower the creep properties of steel. Silicon increases the electrical resistivity of steel and decreases hysteresis losses.

Silicon contributes greatly to the production of sound steel because of its deoxidizing and degasifying properties. When added in amounts up to 2.5%, the ultimate strength of the steel is increased without loss in ductility. Silicon in excess of 2.5% causes brittleness, and amounts higher than 5% make the steel non-malleable.

Resistance to oxidation and surface stability of steel are increased by the addition of silicon. These desirable effects partially compensate for the tendency of silicon to lower the creep properties of steel. Silicon increases the electrical resistivity of steel and decreases hysteresis losses.

Austenite stabilisers have the effect of extending the temperature RANGE over which austenite is formed. Such elements are carbon, manganese, nickel, copper and COBALT.

Ferrite stabilisers have the effect of extending the temperature range over which alpha and DELTA ferrite are formed, which consequently REDUCES temperature range over which austenite is formed. Such elements are SILICON, chromium, molybdenum, tungsten, titanium and niobium.

Austenite stabilisers have the effect of extending the temperature range over which austenite is formed. Such elements are carbon, manganese, nickel, copper and cobalt.

Ferrite stabilisers have the effect of extending the temperature range over which alpha and delta ferrite are formed, which consequently reduces temperature range over which austenite is formed. Such elements are silicon, chromium, molybdenum, tungsten, titanium and niobium.

1. To alter the transformation temperatures and times
2. To modify the room temperature and elevated temperature strengths of GIVEN structures by
   1. stiffening the crystals and
   2. introducing COMPLEX precipitates which tend to harden the steel.
3. To modify the type of oxide FILM formed on the surface of the steel and thereby affect its corrosion RESISTANCE.

A prerequisite to the hardening of steels is that martensite should be formed on cooling, but this can only be ACHIEVED if the rate of cooling is great ENOUGH to suppress the formation of pearlite or bainite and in PLAIN carbon steels this can be achieved by quenching relatively SMALL specimens

A prerequisite to the hardening of steels is that martensite should be formed on cooling, but this can only be achieved if the rate of cooling is great enough to suppress the formation of pearlite or bainite and in plain carbon steels this can be achieved by quenching relatively small specimens

The shape and distribution of the carbides in the iron DETERMINES the HARDNESS of the steel. Carbides can be dissolved in austenite is the basis of the heat treatment of steel. If steel is heated above the A CRITICAL temperature to dissolve all the carbides, and then COOLED, suitable cooling through the cooling range will produce the desired size and distribution of carbides in the ferrite, IMPARTING different properties.

The shape and distribution of the carbides in the iron determines the hardness of the steel. Carbides can be dissolved in austenite is the basis of the heat treatment of steel. If steel is heated above the A critical temperature to dissolve all the carbides, and then cooled, suitable cooling through the cooling range will produce the desired size and distribution of carbides in the ferrite, imparting different properties.

CHROMIUM and NICKEL.

Chromium and nickel.

FERRITE and it is SOFT.

Ferrite and it is soft.

Styrene-butadiene RUBBER.

Styrene-butadiene rubber.

It is the TEMPERATURE at which the PHASE CHANGE OCCURS in METALS.

It is the temperature at which the phase change occurs in metals.

KILLED STEELS are deoxidised in the ladle with silicon and ALUMINIUM. On SOLIDIFICATION no gas evolution occurs in these steels because they are free from oxygen.

Killed steels are deoxidised in the ladle with silicon and aluminium. On solidification no gas evolution occurs in these steels because they are free from oxygen.

GAMMA RAYS.

Gamma rays.

It is a non-ferrous cast alloy CONTAINING COBALT, chromium and TUNGSTEN.

It is a non-ferrous cast alloy containing cobalt, chromium and tungsten.

4%.

4%.

PERT is BASED on the approach of multiple time ESTIMATES for each ACTIVITY.

PERT is based on the approach of multiple time estimates for each activity.

The TEMPERATURES at which the phase CHANGES occur are CALLED CRITICAL points (or temperatures).

The temperatures at which the phase changes occur are called critical points (or temperatures).

Ferrite is the solid solution of carbon and other CONSTITUENTS in alpha-iron. It is soft, ductile and relatively WEAK.

Austenite is the solid solution of carbon and other constituents in gamma-iron. It exists in ordinary STEELS at elevated temperatures, but it is also found at ordinary temperatures in some stainless steels. GRAPHITE has a hexagonal layer LATTICE.

Ferrite is the solid solution of carbon and other constituents in alpha-iron. It is soft, ductile and relatively weak.

Austenite is the solid solution of carbon and other constituents in gamma-iron. It exists in ordinary steels at elevated temperatures, but it is also found at ordinary temperatures in some stainless steels. Graphite has a hexagonal layer lattice.

Both column and strut carry compressive LOAD. Column is ALWAYS vertical but strut as member of structure could carry AXIAL compressive load in any DIRECTION.

Both column and strut carry compressive load. Column is always vertical but strut as member of structure could carry axial compressive load in any direction.

Proof RESILIENCE is the maximum strain ENERGY that can be stored in a material without PERMANENT deformation. MODULUS of resilience is the maximum strain energy stored in a material per unit volume.

Proof resilience is the maximum strain energy that can be stored in a material without permanent deformation. Modulus of resilience is the maximum strain energy stored in a material per unit volume.

At POINTS of inflexion in a loaded beam the bending moment is ZERO and at points of CONTRAFLEXURE in loaded beam the bending moment CHANGES sign from INCREASING to decreasing.

At points of inflexion in a loaded beam the bending moment is zero and at points of contraflexure in loaded beam the bending moment changes sign from increasing to decreasing.

In HOMOGENEOUS material the COMPOSITION is same throughout and in isotropic material the elastic CONSTANTS are same in all DIRECTIONS.

In homogeneous material the composition is same throughout and in isotropic material the elastic constants are same in all directions.

The bcc FORM of iron EXISTS between room temperature and 910°C, and between 1400°C and the melting point at 1539°C. The lower temperature form is KNOWN as "ALPHA"-iron and the higher temperature form as "delta"-iron. The face-centered CUBIC form existing between 910°C and 1400°C is referred to as "gamma-iron".

The bcc form of iron exists between room temperature and 910°C, and between 1400°C and the melting point at 1539°C. The lower temperature form is known as "alpha"-iron and the higher temperature form as "delta"-iron. The face-centered cubic form existing between 910°C and 1400°C is referred to as "gamma-iron".

Some ELEMENTS EXIST in more than one CRYSTALLINE form. Each form is KNOWN as "allotrope". Iron EXISTS in two forms of cubic pattern, namely body centered cubic (bcc) and face-centered cubic (fee).

Some elements exist in more than one crystalline form. Each form is known as "allotrope". Iron exists in two forms of cubic pattern, namely body centered cubic (bcc) and face-centered cubic (fee).

Excessive hydrogen results in the FORMATION of small fissures often described as hairline CRACKS or flakes in the STEEL. Large forgings in ALLOY steel are PARTICULARLY sensitive to this phenomenon.

Excessive hydrogen results in the formation of small fissures often described as hairline cracks or flakes in the steel. Large forgings in alloy steel are particularly sensitive to this phenomenon.

Oxygen can be removed by adding elements such as manganese, silicon or aluminium which, because of their high AFFINITY for oxygen, REACT with it to form non-metallic OXIDES which rise into the slag. STEELS which have had most of their DISSOLVED oxygen removed are called "fully killed steels".

Oxygen can be removed by adding elements such as manganese, silicon or aluminium which, because of their high affinity for oxygen, react with it to form non-metallic oxides which rise into the slag. Steels which have had most of their dissolved oxygen removed are called "fully killed steels".

For SPRINGS and GEARS RESPECTIVELY.

For springs and gears respectively.

ROUGHNESS, ENTHALPY, TOUGHNESS, and HARDNESS RESPECTIVELY.

Roughness, enthalpy, toughness, and hardness respectively.

Pearlite is EUTECTOID MIXTURE of FERRITE and CEMENTITE. Cementite is chemical COMPOUND of iron and carbon.

Pearlite is eutectoid mixture of ferrite and cementite. Cementite is chemical compound of iron and carbon.

FERRITE and AUSTENITE RESPECTIVELY.

Ferrite and austenite respectively.

It is a SOLID FORMED by COMBINATION of METALLIC and non-metallic ELEMENTS.

It is a solid formed by combination of metallic and non-metallic elements.

GREY CAST iron with TENSILE STRENGTH of 250 MPA.

Grey cast iron with tensile strength of 250 MPa.

Copper.

Copper.

Convective heat transfer is effected between a solid and fluid by a combination of molecular conduction within the fluid in combination with ENERGY transport RESULTING from the MOTION of fluid particles. It depends on BOUNDARY layer configuration, fluid properties and temperature DIFFERENCE.

Convective heat transfer is effected between a solid and fluid by a combination of molecular conduction within the fluid in combination with energy transport resulting from the motion of fluid particles. It depends on boundary layer configuration, fluid properties and temperature difference.

1. AREA of the section of the heat FLOW path, PERPENDICULAR to the DIRECTION of heat flow.
2. temperature gradient, i.e. change of temperature w.r.t. LENGTH of path.
3. Thermal conductivity of material.

Thermal diffusivity is ASSOCIATED with the SPEED of propagation of heat into SOLIDS during changes in TEMPERATURE with TIME.

Thermal diffusivity is associated with the speed of propagation of heat into solids during changes in temperature with time.

For DUCTILE materials, theories of failure USED are maximum SHEAR stress theory, and maximum ENERGY of distortion theory; while for brittle materials, theory of maximum principal stress, and maximum STRAIN are used.

For ductile materials, theories of failure used are maximum shear stress theory, and maximum energy of distortion theory; while for brittle materials, theory of maximum principal stress, and maximum strain are used.

Manner of loading, and the RATE of loading PROMOTE transition from ductile to brittle fracture. A machine MEMBER may have ductile failure under static loading but may fail in brittle fashion when the load is fluctuating. Similarly a material may evidence ductile failure under tensile loading at ordinary testing SPEED but if load is applied at a high velocity then failure may be brittle.

Manner of loading, and the rate of loading promote transition from ductile to brittle fracture. A machine member may have ductile failure under static loading but may fail in brittle fashion when the load is fluctuating. Similarly a material may evidence ductile failure under tensile loading at ordinary testing speed but if load is applied at a high velocity then failure may be brittle.

Normal carburising/nitriding treatments increase VOLUME due to phase TRANSFORMATION at Surface and introduce residual compressive surface stress and THUS increase the fatigue strength. By excessive treatment the high compressive STRESSES are introduced but these are balanced by high in¬ternal tensile stresses of equal value and the SUBSURFACE fatigue cracks may develop in the regions of high tensile stress and lead to early fatigue failure.

Normal carburising/nitriding treatments increase volume due to phase transformation at Surface and introduce residual compressive surface stress and thus increase the fatigue strength. By excessive treatment the high compressive stresses are introduced but these are balanced by high in¬ternal tensile stresses of equal value and the subsurface fatigue cracks may develop in the regions of high tensile stress and lead to early fatigue failure.

PERFECTION of material conditions is possible at lower SIZES and as size increases, it is not possible to ATTAIN uniform structure of the material.

Perfection of material conditions is possible at lower sizes and as size increases, it is not possible to attain uniform structure of the material.

A STRESS in excess of elastic limit, with no external force to OPPOSE it, will RELIEVE itself by plastic deformation until it reaches the VALUE of the yield stress.

A stress in excess of elastic limit, with no external force to oppose it, will relieve itself by plastic deformation until it reaches the value of the yield stress.