43. Hardness of steel depends on
A.Amount of carbon it contains
B.The shape and distribution of the carbides in iron
C.Method of fabrication
D.Contents of alloying elements

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44. Maximum percentage of carbon in ferrite is
A.0.025%
B.0.06%
C.0.1%
D.0.25%

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45. Maximum percentage of carbon in austenite is
A.0.025%
B.0.26%
C.0.8%
D.1.7%

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46. Corrosion resistance of steel is increased by addition of
A.Chromium and nickel
B.Sulphur, phosphorus, lead
C.Vanadium, aluminium
D.Tungsten, molybdenum, vanadium, chromium

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47. In which of the following cases, consideration of creep is important
A.Flywheel of steam engine
B.Cast iron pipes
C.Cycle chains
D.Gas turbine blades

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48. The most effective inhibitor of grain growth, when added in small quantities is
A.Carbon
B.Vanadium
C.Manganese
D.Cobalt

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49. Depth of hardness of steel is increased by addition of
A.Nickel
B.Chromium
C.Tungsten
D.Vanadium

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