Which of the following impurity in cast iron makes it hard and brittle?

A Silicon
B Sulphur
C Manganese
D Phosphorus

Correct Answer: Sulphur

Sulfur is normally regarded as an impurity and has an adverse effect on impact properties when a steel is high in sulphur and low in manganese.
Sulphur improves machinability but lowers transverse ductility and notched impact toughness and has little effects on the longitudinal mechanical properties.
Bissoy MCQ
#Mechanical Engineering #Engineering Materials

Related Questions

When filing or machining cast iron makes our hands black, then it shows that ________ is present in cast iron.
A Cementite
B Free graphite
C Both A and B
D None of these
White cast iron as compared to grey cast iron is
A More durable
B Very brittle
C Very hard
D All of the above
When carbon in the cast iron is principally in the form of graphite, the cast iron will be of
A Brown colour
B Yellow colour
C White colour
D Grey colour
Nodular cast iron is produced by adding ________ to the molten cast iron.
A Nickel
B Chromium
C Copper
D Magnesium
An important property of malleable cast iron in comparison to grey cast iron is the high
A Compressive strength
B Ductility
C Carbon content
D Hardness
__________ of grey cast iron produces white cast iron.
A Tempering
B Rapid heating
C Rapid cooling
D Slow cooling
Addition of small amount of __________ to grey cast iron is done to produce nodular grey cast iron.
A Manganese
B Phosphorous
C Magnesium
D Chromium
Which of the following impurity in cast iron promotes graphite nodule formation and increases the fluidity of the molten metal?
A Silicon
B Sulphur
C Manganese
D Phosphorus
Hard and tough materials like cast iron should be turned at
A Slow speed
B High speed
C Any speed
D Certain specific speed
__________ iron is produced by the annealing of white cast iron.
A Malleable
B Nodular
C Ductile
D Grey

Next steps