What should be added to pure iron to make stainlass steel ?

Options

A. nickel and cobalt
B. cadmium annd chromium
C. nickel and cadmium
D. chromium and nickel

Answer

To make stainless steel from pure iron, the following steps can be followed:

### Step-by-Step Solution:

1. **Identify the Base Metal**: Start with pure iron as the base metal. Pure iron is known for its malleability and ductility but is prone to rusting and corrosion.

2. **Add Chromium**: Introduce chromium to the pure iron. The typical percentage of chromium added is about 10.5% or more. Chromium is a reactive metal that contributes to the formation of a protective oxide layer on the surface of the steel, which prevents rusting.

3. **Add Nickel**: Along with chromium, add nickel to the mixture. Nickel is usually added in amounts ranging from 8% to 12%. Nickel enhances the toughness and ductility of the stainless steel and also contributes to its corrosion resistance.

4. **Mixing and Melting**: The iron, chromium, and nickel should be thoroughly mixed and melted together to form a homogeneous alloy. This process typically occurs in a furnace.

5. **Cooling and Solidification**: Once the mixture is melted, it should be cooled and allowed to solidify. The resulting material is stainless steel, which has improved properties compared to pure iron.

6. **Final Processing**: The stainless steel can then be processed further into various shapes and forms as required for its applications.

### Summary:
To make stainless steel, you need to add chromium and nickel to pure iron. Chromium helps in creating a passive layer that protects against corrosion, while nickel enhances the overall properties of the steel.

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