120. The tensile strength of wrought iron is maximum
A.Along the lines of slag distribution
B.Perpendicular to lines of slag distribution
C.Uniform in all directions
D.Unpredictable
121. Balls for ball bearings are made of
A.Cast iron
B.Mild steel
C.Stainless steel
D.Carbon-chrome steel
122. Malleable cast iron
A.Contains 1.21 to 3.5% carbon in free state and is obtained by the slow cooling of molten cast iron
B.Is also known as chilled cast iron and is obtained by cooling rapidly. It is almost unmachinable
C.Is produced by annealing process. It is soft, tough, and easily machined metal
D.Is produced by small additions of magnesium (or cerium) in the ladle. Graphite is in the nodular or spheroidal form and is well dispersed throughout the material
123. Preheating is essential in welding
A.Cast iron
B.High speed steel
C.All non-ferrous materials
D.All of the above
124. The hardness of steel primarily depends on
A.%age of carbon
B.Shape of carbides and their distribution in iron
C.Heat treatment employed
D.Method of manufacture
125. Steel made from phosphatic iron is
A.Brittle
B.Hard
C.Ductile
D.Tough
126. Ductile cast iron
A.Contains 1.7 to 3.5% carbon in free state and is obtained by the slow cooling of molten cast iron
B.Is also known as chilled cast iron and is obtained by cooling rapidly. It is almost unmachinable
C.Is produced by annealing process. It is soft, tough and easily machined metal
D.Is produced by small additions of magnesium (or creium) in the ladle. Graphite is in nodular or spheroidal form and is well dispersed throughout the material
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