The operation in which oil is permeated into the pores of a powder metallurgy product is known as
Mixing
Sintering
Impregnation
Infiltration
Correct Answer :
C. Impregnation
Related Questions
What is the name of the device used in arc welding circuits for the purpose of modifying the rate of current change when the weld road is varied rapidly?
Reactor
Kerf
Inductor
Cone
The chuck preferred for quick setting and accurate centering of a job is
Four jaw independent chuck
Collect chuck
Three jaw universal chuck
Magnetic chuck
A left hand tool on a lathe cuts most efficiently when it travels
From left to right end of the lathe bed
From right to left end of the lathe bed
With the help of a compound slide
Across the bed
The operation performed on a shaper is
Machining horizontal surface
Machining vertical surface
Machining angular surface
All of these
The chamfering is an operation of
Bevelling the extreme end of a workpiece
Embossing a diamond shaped pattern on the surface of a workpiece
Reducing the diameter of a workpiece over a very narrow surface
Enlarging the end of a hole cylindrically
The tool may fail due to
Cracking at the cutting edge due to thermal stresses
Chipping of the cutting edge
Plastic deformation of the cutting edge
All of these
Jigs are used
For holding and guiding the tool in drilling, reaming or tapping operations
For holding the work in milling, grinding, planing or turning operations
To check the accuracy of workpiece
None of the above
A coarse grained grinding wheel is used to grind
Hard and brittle materials
Soft and ductile materials
Hard and ductile materials
Soft and brittle materials
In metal machining, the work-tool contact zone is a zone where heat is generated due to
Plastic deformation of metal
Burnishing friction
Friction between the moving chip and the tool face
None of the above
The drill spindles are provided with standard taper known as
Morse taper
Seller's taper
Chapman taper
Brown and Sharpe taper
The cutting speed for drilling aluminium, brass and bronze with carbon steel drills is _________ cutting speed for drilling mild steel with high speed steel drills.
Equal to
Less than
More than
None of these
The specific cutting energy used for establishing the machinability of the metal depends upon its
Coefficient of friction
Microstructure
Work hardening characteristics
All of these
In gear hobbing
Only hob rotates
Only gear blank rotates
Both hob and gear blank rotates
Neither hob nor gear blank rotates
Which one of the following is a solid state joining process?
Gas tungsten arc welding
Resistance spot welding
Friction welding
Submerged arc welding
What is the type of welding defect caused due to poor manipulation of weld rod or a dirty joint called?
Porosity
Undercut
Under fill
Crack
The tool life is said to be over if
Poor surface finish is obtained
There is sudden increase in cutting forces and power consumption
Overheating and fuming due to heat of friction starts
All of the above
In centreless grinding, work place centre will be
Above the line joining the two wheel centres
Below the line joining the two wheel centres
On the line joining the two wheel centres
At the intersection of the line joining the wheel centres with the work place plane
Flank wear depends upon the
Hardness of the work and tool material at the operating temperature
Amount and distribution of hard constituents in the work material
Degree of strain hardening in the chip
All of these
The grooving is an operation of
Bevelling the extreme end of a workpiece
Embossing a diamond shaped pattern on the surface of a workpiece
Reducing the diameter of a workpiece over a very narrow surface
Enlarging the end of a hole cylindrically
Cast iron during machining produces
Continuous chips
Discontinuous chips
Continuous chips with built-up edge
None of these
Friction at the tool-chip interface can be reduced by
Decreasing the rake angle
Increasing the depth of cut
Decreasing the cutting speed
Increasing the cutting speed
The angle between the lathe centres is
30°
45°
60°
90°
The factor responsible for the formation of discontinuous chips is
Low cutting speed and large rake angle
Low cutting speed and small rake angle
High cutting speed and large rake angle
High cutting speed and small rake angle
The angle between the shear plane and __________ is called shear angle.
Work surface
Tool face
Machine surface
None of these
The main purpose of a boring operation, as compared to drilling, is to
Drill a hole
Finish the drilled hole
Correct the hole
Enlarge the existing hole
For turning internal tapers, the suitable method is
By a form tool
By setting over the tail stock
By a taper turning attachment
By swivelling the compound rest
If the tearing efficiency of a riveted joint is 50%, then ratio of rivet hole diameter to the pitch of rivets is
0.20
0.30
0.50
0.60
The crystal structure of austenite is
Body centred cubic
Base centred cubic
Hexagonal closed packed
Body centred tetragonal
A right hand tool on a lathe cuts most efficiently when it travels
From left to right end of the lathe bed
From right to left end of the lathe bed
With the help of a compound slide
Across the bed
Glazing in grinding wheels takes place when the
Wheel is too hard or wheel revolves at a very high speed
Wheel is too soft or wheel revolves at a very slow speed
Wheel is too hard and wheel revolves at very slow speed
Wheel is too soft and wheel revolves at a very high speed