The steel widely used for motor car crankshafts is

Solution (By Examveda Team)

Option A: Nickel steel This statement is incorrect. While nickel steel is used for some applications requiring strength and toughness, it is not the most common steel used for motor car crankshafts. Nickel steel has good toughness and resistance to impact, but it does not offer the same overall performance as nickel-chrome steel in this specific application.

Option B: Chrome steel This statement is incorrect. Chrome steel is a type of steel alloyed with chromium, which gives it high wear resistance and hardness. However, chrome steel alone does not have the ideal combination of strength and toughness required for motor car crankshafts.

Option C: Nickel-chrome steel This statement is correct. Nickel-chrome steel is widely used for motor car crankshafts because it combines the strength and hardness of chromium with the toughness and impact resistance of nickel. This makes it highly suitable for high-stress components such as crankshafts. The alloy offers excellent resistance to wear and fatigue, which are crucial for crankshaft performance.

Option D: Silicon steel This statement is incorrect. Silicon steel is primarily used for electrical applications, such as transformers and electric motor cores. It is not commonly used in motor car crankshafts because it does not provide the necessary strength and toughness required for such mechanical components.

Therefore, the correct answer is Option C: Nickel-chrome steel, as it is the most commonly used steel for motor car crankshafts due to its ideal combination of strength, toughness, and resistance to wear.