Admiralty brass used for steam condenser tubes contains copper and zinc in the following ratio
50 : 50
30 : 70
70 : 30
40 : 60
Correct Answer :
B. 30 : 70
Related Questions
Which is the false statement about wrought iron? It has
High resistance to rusting and corrosion
High ductility
Ability of hold protective coating
Uniform strength in all directions
Hardness of lower bainite (tempered martensite) is about
RC 65
RC 48
RC 57
RC 80
Manganese in steel increases its
Tensile strength
Hardness
Ductility
Fluidity
Which of the following is not the correct method of increasing fatigue limit?
Shot peening
Nitriding of surface
Cold working
Surface decarburisation
The usual composition of a soldering alloy is
Tin, lead and small percentage of antimony
Tin and lead
Tin, lead and silver
Tin and copper
Which of the following pipes is least corrosion resistant?
Brass
Mild steel
Cast iron
Wrought iron
The correct sequence for descending order of machinability is
Grey cast iron, low carbon steel, wrought iron
Low carbon steel, grey cast iron, wrought iron
Wrought iron, low carbon steel, grey cast iron
Wrought iron, grey cast iron, low carbon steel
Addition of copper to aluminium results in
Improvement of casting characteristics
Improvement of corrosion resistance
One of the best known age and precipitation hardening systems
Improving machinability
Corrosion resistance of steel is increased by addition of
Chromium and nickel
Sulphur, phosphorus, lead
Vanadium, aluminium
Tungsten, molybdenum, vanadium, chromium
Malleable cast iron is produced
By adding magnesium to molten cast iron
By quick cooling of molten cast iron
From white cast iron by annealing process
None of these
The lower critical temperature
Decreases as the carbon content in steel increases
Increases as the carbon content in steel increases
Is same for all steels
Depends upon the rate of heating
Sulphur in pig iron tends to make it
Hard
Soft
Ductile
Tough
The addition of which of the following improves machining of copper?
Sulphur
Vanadium
Tin
Zinc
Weld decay is the phenomenon found with
Cast iron
Mild steel
Nonferrous materials
Stainless steel
When medium carbon steel is heated to coarsening temperature
There is no change in grain size
The average grain size is a minimum
The grain size increases very rapidly
The grain size first increases and then decreases very rapidly
Bronze contains
70% copper and 30% zinc
90% copper and 10% tin
85 - 92% copper and rest tin with little lead and nickel
70 - 75% copper and rest tin
The alloying element which reduces the formation of iron sulphide in steel is
Chromium
Nickel
Vanadium
Manganese
Elinvar, an alloy used in precision instruments, hair springs for watches, etc. contains the following element as principal alloying element
Iron
Copper
Aluminium
Nickel
When low carbon steel is heated up to upper critical temperature
There is no change in grain size
The average grain size is a minimum
The grain size increases very rapidly
The grain size first increases and then decreases very rapidly
Addition of manganese to aluminium results in
Improvement of casting characteristics
Improvement of corrosion resistance
One of the best known age and precipitation hardening systems
Improving machinability
Which of the following element results in presence of free graphite in C.I.?
Carbon
Sulphur
Silicon
Manganese
German silver contains
1% silver
2% silver
5% silver
No silver
The defect which takes place due to imperfect packing of atoms during crystallisation is known as
Line defect
Surface defect
Point defect
None of these
Induction hardening is basically a
Carburising process
Surface hardening process
Core hardening process
None of these
Body centered cubic space lattice is found in
Zinc, magnesium, cobalt, cadmium, antimony and bismuth
Gamma iron, aluminium, copper, lead, silver and nickel
Alpha iron, tungsten, chromium and molybdenum
None of the above
Dye penetrant method is generally used to locate
Core defects
Surface defects
Superficial defects
Temporary defects
Pick up the wrong statement Nickel and chromium in steel help in
Providing corrosion resistance
Improving machining properties
Providing high strength at elevated temperatures
Raising the elastic limit
Monel metal is an alloy of
Nickel and copper
Nickel and chromium
Nickel, Chromium and iron
Copper and chromium
Acidic solution is one which has pH value
Greater than 7
Less than 7
Equal to 7
pH value has nothing to do with neutral solution
Iron-carbon alloys containing carbon ________ 4.3% are known as hypereutectic cast irons.
Equal to
Less than
More than
None of these