DoITPoMS

previous | next

Questions

  1. Three low alloy steels, which differ only in their carbon content (0.1, 0.3 and 0.7 wt% carbon) are characterised using the Jominy end quench test. Select the plot of hardness variation along the test specimen that best describes their behaviour.

    Plots of hardness against distance

    a Plot (a)
    b Plot (b)
    c Plot (c)
    d Plot (d)

  2. Two specimens of a low alloy steel with 0.3wt% carbon are characterised using the Jominy end quench test. One was austenitised at 950°C, and the other was austenitised at 1100°C. Select the plot of hardness variation along the test specimen that best describes their behaviour.

    Plots of hardness against distance

    a Plot (a)
    b Plot (b)
    c Plot (c)
    d Plot (d)

  3. Three medium carbon steels (0.3wt%) that differ only in their Chromium content (0.25, 0.5 and 1 wt%) are characterised using the Jominy end quench test. Select the plot of hardness variation along the test specimen that best describes their behaviour.

    Plots of hardness against distance

    a Plot (a)
    b Plot (b)
    c Plot (c)
    d Plot (d)

  4. You have three steels. Select the most appropriate steel to achieve the necessary levels of mechanical properties, residual stress and distortion in a 1mm diameter wood-working drill.

    a 1% C, 0.4% Si, 1% Mn, 5% Cr, 1% Mo
    b 0.4% C, 0.4% Mn, 0.3% Si
    c 0.5% C, 4% Cr, 6% Mo

  5. Again, you have three steels. Select the most appropriate steel to achieve the necessary levels of mechanical properties, residual stress and distortion in an injection moulding die for a mobile phone plastic case.

    a 1% C, 0.4% Si, 1% Mn, 5% Cr, 1% Mo
    b 0.4% C, 0.4% Mn, 0.3% Si
    c 0.5% C, 4% Cr, 6% Mo

  6. Again, you have three steels. Select the most appropriate steel to achieve the necessary levels of mechanical properties, residual stress and distortion in a tool for high speed milling of steel components.

    a 1% C, 0.4% Si, 1% Mn, 5% Cr, 1% Mo
    b 0.4% C, 0.4% Mn, 0.3% Si
    c 0.5% C, 4% Cr, 6% Mo


previous | next