Question

The elements that DO NOT increase the strength of structural steel are

• A. Carbon
• B. Manganese
• C. Sulphur
• D. Chlorine

Hint:

Steel's strength is primarily improved by elements such as carbon and manganese, whereas impurities like sulphur and elements like chlorine can reduce its mechanical properties.

Answer 1

The Correct Option is C

Step 1: Evaluating the effect of each element on the strength of structural steel: Carbon (Option A): Carbon increases the strength and hardness of steel by improving its hardenability and tensile strength. Manganese (Option B): Manganese contributes to increased strength and toughness, enhancing the overall performance of steel. Sulphur (Option C): Sulphur is considered an impurity in steel. While it improves machinability, it reduces the strength and ductility, leading to brittleness. Chlorine (Option D): Chlorine is not typically a constituent of structural steel and can cause corrosion and degradation rather than improving strength. Step 2: Identifying the correct options: Elements that do not contribute to the strength of structural steel are: \[ \text{Sulphur (C) and Chlorine (D)} \] Conclusion: The correct answer is options (C) and (D), as these elements do not contribute to strengthening structural steel and may instead have adverse effects.