1.
1) The addition of which of the following improves machining of copper?
Correct Answer
A. A. SulpHur
Explanation
The addition of sulphur improves machining of copper.
2.
2). A solder consists of
Correct Answer
A. A. Lead and tin
Explanation
A solder is a metal alloy used to join two or more metal surfaces together. The most common type of solder consists of lead and tin. Lead provides the solder with its softness and ability to melt at a low temperature, while tin improves its strength and durability. This combination of lead and tin creates a solder that is easy to work with and provides a strong bond between metal surfaces.
3.
3). Persence of lead in brass improves
Correct Answer
A. A. Machining properties
Explanation
The presence of lead in brass improves its machining properties. Lead acts as a lubricant during the machining process, reducing friction and heat generation. This allows for smoother and more efficient cutting, shaping, and drilling of the brass material.
4.
4). Brass in an alloy of
Correct Answer
B. B. Copper and zinc
Explanation
Brass is an alloy that is made up of copper and zinc. This combination of metals gives brass its unique properties, such as its yellowish color and its ability to be easily shaped and molded. Copper provides the base for the alloy, while zinc is added to enhance its strength and durability.
5.
5). Bronze is an alloy
Correct Answer
C. C. Copper, zinc and tin
Explanation
Bronze is an alloy made up of copper, zinc, and tin.
6.
6) Babbit metal is an alloy of
Correct Answer
A. A. Tin, antimony and copper
Explanation
Babbit metal is an alloy that is commonly used as a bearing material. It is known for its low friction and excellent wear resistance. The correct answer, A. Tin, antimony, and copper, is the composition of Babbit metal. Tin is the main component, while antimony and copper are added to improve the hardness and strength of the alloy. This combination of metals creates a material that is ideal for applications where low friction and high durability are required, such as in engine bearings.
7.
7) Bell metal is an alloy of
Correct Answer
D. D. Copper and tin
Explanation
Bell metal is an alloy made of copper and tin.
8.
8). Fusible plug for boilers consists of
Correct Answer
D. D. Bismuth, lead and tin
Explanation
Fusible plugs for boilers are safety devices that are designed to melt and release a liquid or gas in order to prevent the boiler from exploding in the event of overheating. The most commonly used materials for fusible plugs are bismuth, lead, and tin. These metals have low melting points, allowing them to melt easily when the temperature of the boiler exceeds a certain threshold. Once melted, the plug releases the liquid or gas, which helps to cool down the boiler and prevent any further damage or explosion.
9.
9). White metal contains
Correct Answer
A. A. Lead and bismuth
Explanation
White metal is an alloy that is commonly used in bearings and bushings. It is known for its low friction and excellent wear resistance. The correct answer, A. Lead and bismuth, is accurate because white metal is typically made by combining lead and bismuth. Lead provides the base for the alloy while bismuth is added to improve the alloy's properties, such as reducing the melting point and increasing the fluidity during casting.
10.
10). Major constituent of phosphor bronze is
Correct Answer
B. B. Copper
Explanation
The major constituent of phosphor bronze is copper. Phosphor bronze is an alloy of copper with a small amount of phosphorus, which gives it improved strength and corrosion resistance. Zinc, lead, aluminium, and phosphorous are not the major constituents of phosphor bronze.
11.
11) Constantan is an alloy containing
Correct Answer
B. B. Copper and nickel
Explanation
Constantan is an alloy that is composed of copper and nickel.
12.
12). Alpha brass is a (an)
Correct Answer
C. C. Substitutional solid solution
Explanation
Alpha brass is a substitutional solid solution because it is a solid solution of zinc in copper. In this type of solid solution, the atoms of the solute (zinc) replace some of the atoms of the solvent (copper) in the crystal lattice. This results in a homogeneous mixture with the solute atoms occupying the lattice sites of the solvent.
13.
13). Silicon when added to copper increases its
Correct Answer
D. D. Hardness
Explanation
When silicon is added to copper, it increases its hardness. This is because silicon forms solid solution with copper, which leads to the formation of a harder and stronger material. The addition of silicon disrupts the crystal lattice structure of copper, making it more resistant to deformation and increasing its hardness. Therefore, the correct answer is D. Hardness.
14.
14) In Muntz metal, if 1% of tin is added it forms _____
ANSWER: naval brass
Correct Answer
B. B. naval brass
Explanation
When 1% of tin is added to Muntz metal, it forms naval brass.
15.
15) What is the composition of cartridge brass?
Correct Answer
C. C. 70 % Cu and 30 % Zn
Explanation
Cartridge brass is a type of brass alloy that is commonly used in the manufacturing of ammunition casings. It is composed of 70% copper (Cu) and 30% zinc (Zn). This composition provides the necessary strength and durability required for cartridge casings while still maintaining good corrosion resistance. The high copper content also allows for good thermal and electrical conductivity, which is important in certain applications.
16.
16) Which of the following cold working operations are suitable for a brass?
Correct Answer
C. C. Both a. and b.
Explanation
Both cold rolling and deep drawing are suitable cold working operations for brass. Cold rolling involves passing the brass through a pair of rollers to reduce its thickness and increase its strength. Deep drawing, on the other hand, involves stretching a sheet of brass over a die to form a desired shape. Both of these operations can be performed on brass without causing it to crack or fracture, making them suitable choices for cold working this material.
17.
17) A bearing material should not possess the characteristic of high ______.
Correct Answer
A. A. coefficient of friction
Explanation
A bearing material should not possess the characteristic of high coefficient of friction because a high coefficient of friction would result in increased resistance and heat generation, leading to wear and damage of the bearing. A low coefficient of friction is desirable as it allows for smooth and efficient movement of the bearing, reducing frictional losses and improving the overall performance and lifespan of the bearing.
18.
18. An alloy which does not contain copper is
Correct Answer
B. (b) Magnalium
Explanation
Magnalium is an alloy that is composed of aluminum and magnesium. It does not contain copper. Bronze, brass, and bell metal all contain copper as one of their main components. Therefore, the correct answer is Magnalium.
19.
19) Which of the following is not a property of copper alloy?
Correct Answer
C. C. High strength
Explanation
Copper alloys are known for their high electrical and thermal conductivity, making them ideal for applications in electrical wiring and heat exchangers. However, they are not known for their high strength compared to other metals like steel or titanium. Copper alloys are typically softer and more malleable, which makes them easier to shape and form but also limits their strength. Therefore, high strength is not a property of copper alloys.
20.
20) Copper when alloyed with zinc is known as
Correct Answer
A. A. Brass
Explanation
Copper when alloyed with zinc is known as brass. Brass is a yellowish alloy made by combining copper and zinc in varying proportions. It is a commonly used material in the manufacturing industry due to its desirable properties such as low friction, excellent electrical conductivity, and resistance to corrosion. Brass is used in a wide range of applications including musical instruments, plumbing fittings, decorative items, and electrical connectors.
21.
21) Brass is an alloy of
Answer: Option A
Correct Answer
A. A. copper and zinc
Explanation
Brass is an alloy made by combining copper and zinc. It is a widely used alloy due to its desirable properties such as high corrosion resistance, low friction, and excellent conductivity. The addition of zinc to copper gives brass its unique characteristics and makes it suitable for various applications, including musical instruments, plumbing fittings, and decorative items.
22.
22) Which of the following has a fine gold colour and is used for imitation jewellery?
Correct Answer
B.
B. Aluminium bronze
Explanation
Aluminium bronze is a type of bronze alloy that has a fine gold color. It is commonly used for imitation jewelry because of its resemblance to gold. Silicon bronze, gun metal, and babbit metal do not have the same gold color and are not typically used for imitation jewelry.
23.
23) Brass is an alloy of Answer:
Correct Answer
A. A. copper and zinc
Explanation
Brass is an alloy made by combining copper and zinc. It is a popular metal alloy due to its durability, malleability, and attractive golden color. The amount of copper and zinc can vary, resulting in different types of brass with varying properties. However, the basic composition of brass always includes copper and zinc.
24.
24) Which of the following has a fine gold colour and is used for imitation jewellery?
Correct Answer
B. B. Aluminium bronze
Explanation
Aluminium bronze is a type of bronze alloy that has a fine gold color. It is commonly used for imitation jewelry because of its resemblance to gold. Silicon bronze, gun metal, and babbit metal do not have the same gold color and are not typically used for imitation jewelry.
25.
25) Cartidge brass can be
Correct Answer
D. D. any one of these
Explanation
Cartidge brass can undergo different manufacturing processes such as cold rolling, drawing, or forming to be transformed into sheets, wires, or tubes. Therefore, the correct answer is D. any one of these.
26.
26)The metal suitable for bearings subjected to light loads, is
Correct Answer
D. D. pHospHor bronze
Explanation
Phosphor bronze is a type of bronze alloy that contains a small amount of phosphorus, which improves its strength, wear resistance, and corrosion resistance. It is commonly used for bearings subjected to light loads because it has good friction properties and can withstand low to moderate speeds and pressures. Silicon bronze, monel metal, and white metal are not as suitable for bearings subjected to light loads as phosphor bronze.
27.
27)An aluminium alloy with 11% silicon is used for making engine pistons by die casting technique.
Correct Answer
A. A. Yes
Explanation
An aluminium alloy with 11% silicon is suitable for making engine pistons by die casting technique. The addition of silicon improves the casting properties of the alloy, such as its fluidity and shrinkage resistance, making it ideal for die casting. Additionally, the alloy's high strength and heat resistance make it suitable for the demanding conditions of an engine piston. Therefore, the statement is correct.
28.
28) Monel metal is an alloy of
Correct Answer
A. A. nickel and copper
Explanation
Monel metal is an alloy that is composed of nickel and copper. This combination of metals gives Monel metal its unique properties, such as resistance to corrosion and high strength. Nickel provides the alloy with excellent resistance to various corrosive environments, while copper contributes to its strength and durability. Therefore, the correct answer is A. nickel and copper.
29.
29) Hindalium is an alloy of aluminium and magnesium with a small quantity of chromium.
Answer: Option A
Correct Answer
A. A. Agree
Explanation
Hindalium is indeed an alloy of aluminium and magnesium with a small quantity of chromium. This means that option A, which states "Agree," is the correct answer.
30.
30) Beryllium bronze has
Correct Answer
C. C. both (a) and (b)
Explanation
Beryllium bronze is a copper alloy that contains a small amount of beryllium. This alloy is known for its high strength and hardness, making it suitable for applications that require high yield point and fatigue limit. The addition of beryllium enhances the mechanical properties of the alloy, resulting in improved strength and fatigue resistance. Therefore, option C is the correct answer as beryllium bronze exhibits both a high yield point and a high fatigue limit.
31.
31) The aluminium alloy, mainly used, for anodized utensil manufacture, is
Correct Answer
D. D. hindalium
Explanation
Hindalium is an aluminium alloy that is commonly used for anodized utensil manufacture. Anodizing is an electrochemical process that creates a protective layer on the surface of the aluminium, increasing its resistance to corrosion and improving its durability. Hindalium is specifically designed to have the necessary properties for this process, making it an ideal choice for anodized utensil manufacture.
32.
32) Bronze is an alloy of
Correct Answer
B. B. copper and tin
Explanation
Bronze is an alloy made from copper and tin. It is a popular material for making statues, tools, and musical instruments due to its strength, durability, and resistance to corrosion. The addition of tin to copper gives bronze its unique properties, making it suitable for various applications throughout history.
33.
33) Tin base white metals are used where the bearings are subjected to
Correct Answer
A. A. large surface wear
Explanation
Tin base white metals are used in bearings where there is large surface wear. This is because tin base white metals have good anti-friction properties and can withstand high levels of wear and tear. They provide a smooth surface for the bearing to rotate on, reducing friction and preventing damage to the bearing. Therefore, they are ideal for applications where there is a lot of surface wear, such as heavy machinery or industrial equipment.
34.
34) An alloy of copper, tin and zinc is known as
Correct Answer
C. C. gun metal
Explanation
Gun metal is an alloy made of copper, tin, and zinc. It is commonly used in the manufacturing of firearms, hence the name "gun metal." The addition of tin and zinc to copper improves the strength and hardness of the alloy, making it suitable for applications that require durability and resistance to corrosion. Gun metal is also known for its attractive dark gray color, which adds to its aesthetic appeal in decorative items and jewelry.
35.
35) Duralumin has better strength than Y-alloy at high temperature.
Correct Answer
B. B. False
Explanation
Duralumin does not have better strength than Y-alloy at high temperatures. The correct answer is false.
36.
36) Which of the following metal shrinks most from molten state to solid state?
Correct Answer
D. D. Admirality metal
Explanation
Admirality metal is the correct answer because it is an alloy primarily composed of copper, zinc, and small amounts of other metals. When this alloy cools from its molten state to solid state, it undergoes a significant amount of shrinkage due to the different thermal expansion coefficients of its constituent metals. This makes Admirality metal shrink more than the other options listed.
37.
37) Duralumin contains
Correct Answer
A. A. 3.5 to 4.5% copper, 0.4 to 0.7% magnesium, 0.4 to 0.7% manganese and rest aluminium
Explanation
Duralumin is an aluminum alloy that contains copper, magnesium, manganese, and aluminum. The correct answer states that Duralumin contains 3.5 to 4.5% copper, 0.4 to 0.7% magnesium, 0.4 to 0.7% manganese, and the remaining percentage is aluminum. This composition is consistent with the properties and characteristics of Duralumin, which is known for its high strength, low density, and excellent corrosion resistance.
38.
38) Age hardening is related to
Correct Answer
A. A. duralumin
Explanation
Age hardening is a process used to increase the strength and hardness of certain alloys, such as duralumin. Duralumin is an aluminum alloy that contains small amounts of copper, magnesium, and manganese. During age hardening, the alloy is heated to a specific temperature and then rapidly cooled. This causes the formation of fine precipitates within the alloy, which strengthen the material. Therefore, age hardening is specifically related to duralumin and not the other options given (brass, copper, or silver).
39.
39) Y-alloy contains
Correct Answer
B. B. 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
Explanation
Y-alloy contains 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 the rest is aluminum.
40.
40)
The machinability of aluminium increases when __________ is added to aluminium.
Correct Answer
D. D. lead and bismuth
Explanation
The addition of lead and bismuth to aluminium improves its machinability. These elements act as lubricants during the machining process, reducing friction and improving chip formation. Copper, magnesium, and silicon do not have the same effect on machinability as lead and bismuth.
41.
41) Aluminium has low density and addition of silicon improves its fluidity and therefore, its castability.
Correct Answer
A. A. Correct
Explanation
Aluminium has low density, which means it is lightweight. The addition of silicon improves its fluidity, making it easier to pour into molds and giving it better flow properties. This improvement in fluidity enhances its castability, making it a suitable material for casting processes.
42.
42) Babbit metal is a
Correct Answer
C.
C. tin-base alloy
Explanation
Babbit metal is a tin-base alloy.
43.
43) The metal suitable for bearings subjected to heavy loads, is
Correct Answer
B.
B. white metal
Explanation
White metal is the most suitable metal for bearings subjected to heavy loads. It has excellent load-bearing properties and can withstand high pressure and friction. White metal is often used in heavy machinery and industrial applications where there is a need for durable and reliable bearings. It has low friction and good resistance to wear, making it an ideal choice for heavy load-bearing applications.
44.
44) Nickel when added to copper improves
Correct Answer
B. B. hardness
Explanation
When nickel is added to copper, it improves the hardness of the copper. Nickel is known to have a higher hardness than copper, so when it is added to copper, it increases the overall hardness of the alloy. This can be beneficial in applications where hardness is important, such as in the manufacturing of tools or machinery parts that require durability and resistance to wear and tear.
45.
45) Which of the following statement is incorrect about duralumin?
Correct Answer
D. D. It is lighter than pure aluminium
Explanation
Duralumin is a type of aluminum alloy that is commonly used in the aerospace industry. It is known for its strength and lightness, but it is not lighter than pure aluminum. In fact, duralumin is slightly denser than pure aluminum. Therefore, statement D is incorrect.
46.
46) Beryllium bronze contains
Correct Answer
C. C. 97.75% copper and 2.25% beryllium
Explanation
Beryllium bronze is an alloy that contains a high percentage of copper and a small percentage of beryllium. The correct answer, C, states that beryllium bronze contains 97.75% copper and 2.25% beryllium. This composition is consistent with the typical composition of beryllium bronze, which is known for its high strength, hardness, and corrosion resistance.
47.
47) The addition of manganese to aluminium improves corrosion resistance.
Correct Answer
A. A. Correct
Explanation
The addition of manganese to aluminium improves corrosion resistance because manganese forms a protective oxide layer on the surface of the aluminium, which helps to prevent corrosion. This oxide layer acts as a barrier, preventing oxygen and moisture from reaching the underlying aluminium and causing corrosion. Therefore, adding manganese to aluminium enhances its ability to resist corrosion.
48.
48) Admirality gun metal contains
Correct Answer
D. D. 88% copper, 10% tin and 2% zinc
Explanation
Admirality gun metal is an alloy that is primarily composed of copper. The correct answer, D, states that Admirality gun metal contains 88% copper, 10% tin, and 2% zinc. This composition suggests that the alloy has a high copper content, which is consistent with the properties of Admirality gun metal. The addition of tin and zinc may provide additional strength and corrosion resistance to the alloy.
49.
49) The percentage of phosphorus is phosphor bronze is
Correct Answer
A. A. 0.1
50.
50) Phosphor bronze has
Correct Answer
B. B. good wearing qualities and high elasticity
Explanation
Phosphor bronze is a type of bronze alloy that contains a small amount of phosphorus. It is known for its good wearing qualities and high elasticity, making it suitable for applications where durability and flexibility are important. It is often used in the manufacturing of springs, electrical contacts, and musical instruments. Phosphor bronze also has a moderate resistance to corrosion, but its main advantages lie in its mechanical properties. Therefore, option B is the correct answer.