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
Correct Answer :
A. Tin, lead and small percentage of antimony
Related Questions
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
Which is false statement about annealing? Annealing is done to
Relieve stresses
Harden steel slightly
Improve machining characteristic
Soften material
Aluminium bronze contains aluminium and copper in the ratio of
50 : 50
40 : 60
60 : 40
10 : 90
Blast furnace is used to produce
Pig iron
Cast iron
Wrought iron
Steel
Annealing of white cast iron results in production of
Malleable iron
Nodular iron
Spheroidal iron
Grey iron
Pure iron is the structure of
Ferrite
Pearlite
Austenite
Ferrite and cementite
Which of the following property is desirable in parts subjected to shock and impact loads?
Strength
Stiffness
Brittleness
Toughness
An example of amorphous material is
Zinc
Lead
Silver
Glass
Which of the following material has maximum ductility?
Mild steel
Copper
Nickel
Aluminium
A cold chisel is made of
Mild steel
Cast iron
HSS
High carbon
The hardness of steel primarily depends on
Percentage of carbon
Percentage of alloying elements
Heat treatment employed
Shape of carbides and their distribution in iron
The lower critical point for all steels is
600°C
700°C
723°C
913°C
The temperature at which ferromagnetic alpha iron transforms to paramagnetic alpha iron is
770°C
910°C
1050°C
Below recrystallisation temperature
Duralumin contains
3.5 to 4.5% copper, 0.4 to 0.7% magnesium, 0.4 to 0.7% manganese and rest aluminium
3.5 to 4.5% copper, 1.2 to 1.7% manganese, 1.8 to 2.3% nickel, 0.6% each of silicon, magnesium and iron, and rest aluminium
4 to 4.5% magnesium, 3 to 4% copper and rest aluminium
5 to 6% tin, 2 to 3% copper and rest aluminium
Manganese in steel increases its
Tensile strength
Hardness
Ductility
Fluidity
In the lower part of the blast furnace (zone of fusion), the temperature is
400° to 700°C
800°C to 1000°C
1200°C to 1300°C
1500°C to 1700°C
Malleability of a material can be defined as
Ability to undergo large permanent deformations in compression
Ability to recover its original form
Ability to undergo large permanent deformations in tension
All of the above
Pearlite consists of
13% carbon and 87% ferrite
13% cementite and 87% ferrite
13% ferrite and 87% cementite
6.67% carbon and 93.33% iron
Babbitt metal is a
Lead base alloy
Copper base alloy
Tin base alloy
Cadmium base alloy
The main alloying elements high speed steel in order of increasing proportion are
Vanadium, chromium, tungsten
Tungsten, titanium, vanadium
Chromium, titanium, vanadium
Tungsten, chromium, titanium
The ultimate tensile strength of low carbon steel by working at a high strain rate will
Decrease
Increase
Remain constant
First increase and then decrease
The alloy, mainly used for corrosion resistance in stainless steels is
Silicon
Manganese
Carbon
Chromium
Lead is poured into the joint between two pipes. These pipes may be made of
Cast iron
Vitrified clay
Asbestos cement
Concrete
For the allotropic forms of iron, the points of arrest are
The points where no further change occurs
Constant for all metals
The points where there is no further flow of metal
The points of discontinuity
If a refractory contains high content of silicon, it means refractory is
Acidic
Basic
Neutral
Brittle
Cemented carbide tools are not found to be suitable for cutting
Brass
Cast iron
Aluminium
Steel
Grey cast iron
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
The hardness of steel increases if it contains
Austenite
Martensite
Pearlite
Cementite
Delta metal is an alloy of
Copper, zinc and iron
Iron, nickel and copper
Iron, lead and tin
Iron, aluminium and magnesium
Tungsten in steel
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