German silver contains
Which of the following is added in low carbon steels to prevent them from becoming porous?
The austenite is a solid solution of carbon or iron carbide in gamma-iron.
A steel with 0.carbon is known as
For the pipe fitting like elbow, tee, union etc., which of the following is preferred?
Blast furnace is used to produce
The process which improves the machinability of steels, but lowers the hardness and tensile strength, is
In the austempering process of heat treatment, austenite changes into
The machine tool guide ways are usually hardened by
A steel with carbon __________ is known as hypo-eutectoid steel.
Cast iron is a ductile material.
When a steel containing more than 0.carbon is cooled slowly below the lower critical point, it consists of
Chilled cast iron is produced
The alloying element which reduces the formation of iron sulphide in steel is
When filing or machining cast iron makes our hands black, then it shows that __________ is present in cast iron.
In the lower part of the blast furnace (zone of fusion), the temperature is
Macro-structure of a material is, generally, examined by
There are fourteen atoms in a unit cell of
Free cutting steels
Manganese is added in low carbon steel to
For a steel containing 0.carbon
According to Indian standard specifications, a plain carbon steel designated byC8 means that the carbon content is
Which of the following impurity in cast iron promotes graphite nodule formation and increases the fluidity of the molten metal?
Aluminium has low density and addition of silicon improves its fluidity and therefore, its castability.
The maximum internal diameter of a blast furnace is about
The compressive strength of cast iron is __________ that of its tensile strength.
When a low carbon steel is heated upto lower critical temperature,
The ratio of the volume occupied by the atoms to the total volume of the unit cell is called
The presence of hydrogen in steel causes
Beryllium bronze contains
In high speed steels, manganese is used to tougher the metal and to increase its
The bond formed by transferring electrons from one atom to another is called
Wrought iron
In iron, the presence of carbon in free form is called graphite.
The high speed steel has __________ percentage of tungsten.
The malleability is the property of a material due to which it can be rolled or hammered into thin sheets.
Iron-carbon alloys containing 4.carbon are known as hypo-eutectic cast irons.
Which of the following statement is wrong?
Which of the following iron exists atC?
Which of the following property is desirable for materials used in tools and machines?
In spheroidising process, the steel is
When a steel containing less than 0.carbon is cooled slowly from temperatures above or within the critical range, it consists of
Grey cast iron is __________ than white cast iron.
Which of the following statement is incorrect about duralumin?
The property of a material which enables it to retain the deformation permanently, is called
The portion of the blast furnace below its widest cross-section is called
The machinability of aluminium increases when __________ is added to aluminium.
Which of the following property is desirable in parts subjected to shock and impact loads?
In a body centred cubic space lattice, there are nine atoms out of which eight atoms are located at the corners of the cube and one atom at its centre.
The essential constituent of a hardened steel is