The co-ordination number for fcc crystal structure is
For Rhombohedral space lattice which one of the following is correct
Which of the following is a point imperfection;
2. frenkel defect
4. Schottky defect
Isothermal annealing is mainly used in alloy steel to improne.
The process of reheating to reduce brittleness without any significant loss in hardness is
The main purpose of chaplets is
Green sand mould indicates that
Disposable patterns are made of
The gating ratio 2 : 8 : 1. for copper in gating system refers to the ratio of arae of
Two streams of liquid metal which are not hot enough to fuse properly result into a casting defect known as :-
Shell moulding can be used for.
An expandable pattern is used in
In which of the following metal moulds are used
Which of the following is true for centrifugal casting
If the diameter of the hole is subject to considerable variation, then for locating in jigs and fixtures, the pressure type of locator used is
The major difficulty during welding of aluminium is
The ratio of acetelene to oxygen is approximately _______ for a neutral flame used in gas welding.
In oxy acetelene gas welding the temperature at the inner core of flame is about
In are welding, penetration is minimum for
The coating material of an arc welding electrode contains which of the following
1. Deoxidising agent
2. Arc stabilizing agent
3. Slag forming agent
Arc Blow is more common in
In an inert gas welding, the commonly used gas is
Which of the following are welding process does not used consumable electrodes.
In resistance welding, heat is produced due to resistance between
According to Chvorinov’s equation, the solidification time of a casting is proportional to (V is volume of casting):