151. Which of the following is used for bearing liner
(a) gun metal
(b) bronze
(c) bell metal
(d) babbit metal
(e) brass.
Ans: d
152. The correct sequence for descending order of machinability is
(a) grey cast iron, low carbon steel, wrought iron
(b) low carbon steel, grey cast iron, wrought iron
(c) wrought iron,low carbon steel, grey cast iron
(d) wrought iron, grey cast iron, low carbon steel
(e) grey cast iron, wrought iron, low carbon steel.
Ans: a
153. Structural steel contains following principal alloying elements
(a) nickel, chromium and manganese
(b) tungsten, molybdenum and phosphorous
(c) lead, tin, aluminium
(d) zinc, sulphur, and chromium
(e) none of the above.
Ans: a
154. Aluminium bronze contains aluminium and copper in the ratio of
(a) 50 : 50
(b) 40 : 60
(c) 60 : 40
(d) 10 : 90
(e) 90 : 10.
Ans: d
155. Bronze contains
(a) 70% copper and 30% zinc
(b) 90% copper and 10% tin
(c) 85-92% copper and rest tin with little lead and nickel
(d) 70-75% copper and rest tin
(e) 90% copper and 1C% zinc.
Ans: b
156. Muntz metal contains copper and zinc in the ratio of
(a) 50 : 50
(b) 40 : 60
(c) 60 : 40
(d) 20 : 80
(e) 80 : 20.
Ans: c
157. Gun metal contains
(a) 70% copper and 30% zinc
(b) 90% copper and 10% tin
(c) 85-92% copper and rest tin with little lead and nickel
(d) 70-78% copper and rest tin
(e) 85-92% copper and rest zinc.
Ans: c
158. Perminvar alloy having constant permeability is an alloy of
(a) nickel, copper and iron
(b) nickel, copper and zinc
(c) copper, nickel and antimony
(d) iron, zinc and bismuth
(e) antimony, copper and zinc.
Ans: a
159. The alloy used for making electrical resistances and heating elements is
(a) nichrome
(b) invar
(c) magnin
(d) elinvar
(e) peiminvar.
Ans: a
160. Monel metal contains
(a) 63 to 67% nickel and 30% copper
(b) 88% copper and 10% tin and rest zinc
(c) alloy of tin, lead and cadmium
(d) malleable iron and zinc
(e) none of the above.
Ans: a
163. Permalloy is a
(a) kind of stainless steel
(b) none ferrous alloy
(c) polymer
(d) cutting tool material
(e) nickel and iron alloy having high permeability.
Ans: e
164. Phosphor bronze contains
(a) 0.5% of phosphorous
(b) 1% phosphorous
(c) 2.5% phosphorous
(d) 5% phosphorous
(e) none of the above.
Ans: e
165. Free cutting steels
(a) are used where ease in machining is the criterion
(b) contain carbon in free form
(c) require least cutting force
(d) do not exist
(e) can be cut freely even under adverse conditions.
Ans: a
166. Delta metal is an alloy of
(a) copper, zinc and iron
(b) iron, nickel and copper
(c) iron, lead and tin
(d) iron, aluminium and magnesium
(e) copper, zinc and antimony.
Ans: a
167. Admiralty gun metal contains
(a) 63 to 67% nickel and 30% copper
(b) 88% copper, 10% tin and rest zinc
(c) alloy of tin, lead and cadmium
(d) iron scrap and zinc
(e) none of the above.
Ans: b
168. Which of the following alloys does not contain tin
(a) white metal
(b) solder admiralty
(c) fusible metal
(d) phosphor bronze
(e) gun metal.
Ans: a
169. Which is false statement about properties of aluminium
(a) modulus of elasticity is fairly low
(b) wear resistance is very good
(c) fatigue strength is not high
(d) creep strength limits its use to fairly low temperatures
(e) corrosion resistance is good.
Ans: b
170. Addition of copper to aluminium results in
(a) improvement of casting characteristics
(b) improvement of corrosion resistance
(c) one of the best known age and precipitation-hardening systems
(d) improving machinability
(e) none of the above.
Ans: c
171. Addition of manganese to aluminium results in
(a) improvement of casting charac¬teristics
(b) improvement of corrosion resistance
(c) one of the best known age and precipitation-hardening systems
(d) improving machinability
(e) none of the above.
Ans: b
172. Elinvar, an alloy used in precision instruments, hair springs for watches, etc. contains the following element as principal alloying element
(a) iron
(b) copper
(c) aluminium
(d) zinc
(e) nickel.
Ans: e
173. Which of the following alloys does not have copper as one of the constituents
(a) delta metal
(b) monel metal
(c) constantan
(d) nichrome
(e) silicon bronze.
Ans: d
174. Addition of lead and bismuth to aluminium results in
(a) improvement of casting characteristics
(b) improvement of corrosion resistance
(c) one of the best known age and precipitation-hardening systems
(d) improving machinability
(e) none of the above.
Ans: d
175. Addition of silicon to aluminium results in
(a) improvement of casting characteristics
(b) improvement of corrosion resistance
(c) one of the best known age and precipitation-hardening systems
(d) improving machinability
(e) none of the above.
Ans: a