Effects of Alloying Element

Dear Readers,

We often used alloy steel during our construction activity especially piping works in Power plants & Refineries. 

Alloys are usually stronger than pure metals, although they generally offer reduced electrical and thermal conductivity. Strength is the most important criterion by which many structural materials are judged. Therefore, alloys are used for engineering construction. The synergistic effect of alloying elements and heat treatment produces a tremendous variety of microstructures and properties. Important properties of Alloy Elements are as follows.

1. Carbon (C) : Carbon is a non-metallic element, It is a very strong austenitizer and increases the strength of steel.

2. Manganese (Mn) : Toughness

3. Chromium (Cr) : Hardness, strength, and Corrosion Resistance

4. Vanadium (V) : Strength and grain growth during heat treatment

5. Sulphur (S) : Residual Element

6. Phosphorous (P) : Residual Element

7. Silicon (Si) : < 0.3% Deoxidizer

8. Molybdenum (Mo) : 1% is for creep resistance. hardenability and strength, particularly at high temperatures.

9. Aluminum (Al) :  Grain refiner, < 0.008% deoxidizer + toughness

10. Nickel (Ni) : Low Temperature applications

11. Copper (Cu) : Used for weathering steels

12. Titanium (Ti) : Grain refiner, used as a micro-alloying element ( Strength and Toughness)

13. Niobium (Nb) : Grain refiner, used as a micro-alloying element ( Strength and Toughness)

14. Tungsten (W) : Stable carbides and refines grain size so as to increase hardness, particularly at high temperatures.