Engineering Materials

1

When the dimension is expressed as`20_(- 0.025)^ (+ 0.035)`, then the tolerance is

A. 0.035 mm
B. 0.025 mm
C. 0.01 mm
D. 0.06 mm

2
  A carbon steel having Brinell hardness number 100 should have ultimate tensile strength closer to
A. 100 N/mm2
B. 200 N/mm2
C. 350 N/mm2
D. 1000 N/mm2

3

.During the operation of a bessemer converter, the white flame indicates that the silicon and managenese had burnt and carbon has started oxidising.

A. Agree
B. Disagree

4

The limestone in the charge of a blast furnace decomposes to give lime and carbon dioxide. The lime thus obtained

A. controls the grade of pig iron
B. acts as an iron-bearing mineral
C. supplies heat to reduce ore and melt the iron
D. forms a slag by combining with impurities

5

  Vanadium when added to steel

A. increases tensile strength
B. decreases tensile strength
C. raises critical temperature
D. Sowers critical temperature