Materials Used for Making Crankshaft

1. Manganese-molybdenum Steel:

• Forged crankshafts, suitable for moderate-duty petrol engines.
• Composition: 1.5% manganese, 0.3% molybdenum, 0.38% carbon, and 97.82% iron.
• Brinell hardness number: Approximately 250 BHN.

2. Chromium-molybdenum Steel:

• Used in medium and heavy-duty petrol and diesel engines.
• Composition: 1.2% chromium, 0.4% molybdenum, 0.3% carbon, with the rest being iron.
• Brinell hardness number: Around 280 BHN.

3. Nickel-chromium-molybdenum Steel:

• Ideal for diesel engines with very high fatigue strength.
• Composition: 2.5% nickel, 0.31% carbon, 0.65% chromium, 0.5% molybdenum, and the remaining iron.
• Brinell hardness number: 300 BHN.

4. Nodular Cast Iron:

• A type of grey cast iron with graphite nodules in a perlite medium, known for high ductility.
• Composition: Carbon content around 3-4% and silicon content around 1.8-2.8%.
• Brinell hardness number: Approximately 200-300 BHN.