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Manganese bronze is not typically used as a propeller material .Why


1. High cost: Manganese bronze is a costly alloy, making it less economical for large propellers.

2. Low strength-to-weight ratio: Compared to other propeller materials like nickel-aluminum bronze or stainless steel, manganese bronze has a lower strength-to-weight ratio.

3. Susceptible to corrosion: Manganese bronze can corrode in seawater, especially when exposed to high velocities and turbulence.

4. Poor cavitation resistance: Manganese bronze is more prone to cavitation damage than other materials.

5. Difficult to cast and machine: Manganese bronze is challenging to cast and machine, making it less desirable for complex propeller geometries.

6. Limited weldability: Manganese bronze has poor weldability, making repairs and modifications difficult.


Nickel-aluminum bronze or stainless steel are commonly used for propellers due to their:

- High strength and durability

- Excellent corrosion resistance

- Good cavitation resistance

- Ease of casting and machining

- Weldability

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