Materials and Construction

21. 100% H2SO4 at 30°C can't be stored in a vessel made/lined with

1. Cast iron and high silicon iron
2. Mild steel and stainless steel
3. Aluminium, tin and rubber
4. Teflon, glass and porcelain

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22. 18/8 stainless steel means, that it contains

1. 18% chromium and 8% nickel
2. 18% chromium and 8% molybdenum
3. 18% nickel and 8% chromium
4. 18% molybdenum and 8% chromium

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23. 18/8 steel is a/an _________ stainless steel.

1. Austenitic
2. Ferritic
3. Martensitic
4. None of these

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24. 18-4-1 high speed steel contains 18%, 4% and 1% respectively of

1. Tungsten, vanadium and chromium
2. Tungsten, chromium and vanadium
3. Vanadium, chromium and tungsten
4. Chromium, tungsten and vanadium

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25. A bearing metal should not have

1. Enough plasticity
2. Low thermal conductivity
3. Low co-efficient of friction
4. High toughness

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26. A chemical change takes place when iron

1. Rusts
2. Melts
3. Is heated
4. None of these

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27. A hardened steel essentially contains

1. Sorbite
2. Troostite
3. Martensite
4. None of these

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28. A hardness depth of about 3 mm can be achieved by induction hardness in _________ seconds.

1. 5
2. 100
3. 250
4. 500

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29. A magnetic material becomes _________ above the Curie temperature.

1. Ferromagnetic
2. Diamagnetic
3. Paramagnetic
4. None of these

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30. A material capable of undergoing large permanent deformation, when subjected to compression is termed as

1. Malleable
2. Ductile
3. Brittle
4. None of these

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