Solution:

Effects of Alloying Element on steel:(Any 04 - 01 Mark each)

1) Nickel:

i) It improves Toughness

ii) It improves Tensile Strength

iii) It improves Ductility

iv) It improves Corrosion Resistance

2) Chromium:

i) It improves Ductility

ii) It is added in different proportions upto 18 %

iii) Below 1.5 % addition increases Tensile Strength

iv) 12 % addition gives high Corrosion Resistance

v) It improves Hardenability & Toughness simultaneously

3) Cobalt:

i) It improves Corrosion Resistance

ii) It improves Thermal Resistance

iii) It improves Magnetic Properties

iv) It is act as a Grain Refiner

4) Manganese:

i) Lower proportions from 1.0 to 1.5 % improves Strength & Toughness

ii) Higher proportions upto 5 % improves Hardness

iii) Very Higher proportions from 11 to 14 % improves very degree of Hardness

5) Silicon:

i) It is act as a Ferritic Strengthener

ii) It improves Elastic Limits

iii) It improves Magnetic Property

iv) It decreases Hysteresis Losses

6) Molybdenum:

i) It improves Hardness

ii) It improves Wear Resistance

iii) It improves Thermal Resistance

iv) It gives ability to maintain Mechanical Properties at Elevated Temperatures

7) Tungsten:

i) It improves Hardness

ii) It improves Wear Resistance

iii) It improves thermal Resistance

iv) It improves shock Resistance

v) It improves Magnetic Properties

vi) It gives ability to maintain Mechanical Properties at Elevated Temperatures

8) Vanadium:

i) It improves Elastic Limit

ii) It improves Shock Resistance

iii) It act as a Degasser when added to Molten Metal

9) Boron:

i) It improves Toughness

ii) It improves Tensile Strength

iii) It improves Ductility

iv) It improves Corrosion Resistance

v) It improves Hardenability

vi) It is very useful when alloyed with Low Carbon Steels

10) Aluminium:

i) It improves Tensile Strength

ii) It improves Corrosion Resistance

iii) It is used as a Deoxidizer

iv) It improves growth of Fine Grains

v) It improves Hardness by Nitriding to form Aluminum Nitrides

11) Titanium:

i) It improves Corrosion Resistance

ii) It is good Deoxidizer

iii) It forms titanium carbides means improves hardness

12) Copper:

i) It improves Toughness

ii) It improves corrosion Resistance

iii) It improves Strength

iv) Its proportions varies from 0.2 % to 0.5 %

13) Niobium:

i) It deceases Hardenability

ii) It improves Impact Strength

iii) It improves Fine Grain Growth iv) It is also called as "Columbium ‟