Are formed into shape under heat and pressure and results in a permanently hard product
Do not become hard with the application of heat and pressure and no chemical change occurs
Are flexible and can withstand considerable wear under suitable conditions
Are used as a friction lining for clutches and brakes
B. Do not become hard with the application of heat and pressure and no chemical change occurs
Are formed into shape under heat and pressure and results in a permanently hard product
Do not become hard with the application of heat and pressure and no chemical change occurs
Are flexible and can withstand considerable wear under suitable conditions
Are used as a friction lining for clutches and brakes
Silicon
Sulphur
Manganese
Phosphorus
Core defects
Surface defects
Superficial defects
Temporary defects
Aluminium, copper etc.
Nickel, molybdenum etc.
Nickel, Copper, etc.
All of the above
Make the steel tougher and harder
Raise the yield point
Make the steel ductile and of good bending qualities
All of the above
Nickel and copper
Nickel and chromium
Nickel, Chromium and iron
Copper and chromium
Allotropic change
Recrystallisation
Heat treatment
Precipitation
Can be drawn into wires
Breaks with little permanent distortion
Can cut another metal
Can be rolled or hammered into thin sheets
Six
Twelve
Eighteen
Twenty
Machinability
Hardness
Hardness and strength
Strength and ductility
0.8 %
Below 0.8 %
Above 0.8 %
None of these
Same
Less
More
None of these
Increase hardenability
Reduce machinability
Increase wear resistance
Increase endurance strength
Duralumin
Brass
Copper
Silver
13% carbon and 87% ferrite
13% cementite and 87% ferrite
13% ferrite and 87% cementite
6.67% carbon and 93.33% iron
Face centred cubic space lattice
Body centred cubic space lattice
Close packed hexagonal space lattice
None of these
0.5% of phosphorous
1% phosphorous
2.5% phosphorous
None of the above
0.1 to 0.2 %
0.25 to 0.5 %
0.6 to 0.7 %
0.7 to 0.9 %
Bessemer process
Open hearth process
Electric process
LD process
Promotes decarburisation
Provides high hot hardness
Forms very hard carbides and thus increases wear resistance
Promotes retention of austenite
Improves wear resistance, cutting ability and toughness
Refines grain size and produces less tendency to carburisation, improves corrosion and heat resistant properties
Improves cutting ability and reduces hardenability
Gives ductility, toughness, tensile strength and anticorrosion properties
Decrease
Increase
Remain constant
First increase and then decrease
It easily machinable
It brittle
It hard
The casting unsound
Stainless steel
High speed steel
Heat resisting steel
Nickel steel
Free form
Combined form
Nodular form
Partly in free and partly in combined state
Connecting rods
Cutting tools
Generators and transformers in the form of laminated cores
Motor car crankshafts
Contains 1.7 to 3.5% carbon in Free State and is obtained by the slow cooling of molten cast iron
Is also known as chilled cast iron is obtained by cooling rapidly. It is almost unmachinable
Is produced by annealing process. I is soft, tough and easily machined metal
Is produced by small additions o magnesium (or cerium) in the ladle Graphite is in nodular or spheroidal form and is well dispersed throughout the material
Fixed structure at all temperatures
Atoms distributed in random pattern
Different crystal structures at different temperatures
Any one of the above
Grain growth, recrystallisation, stress relief
Stress relief, grain growth, recrystallisation
Stress relief, recrystallisation, grain growth
Grain growth, stress relief, recrystallisation
Greater than 7
Less than 7
Equal to 7
pH value has nothing to do with neutral solution