Differences Between Cast Iron and Aluminum Alloy Engine Blocks

[LeAdalynn]

There are many differences between cast iron and aluminum alloy engine blocks. Here are the detailed explanations: 1. Weight: Aluminum has a lower specific gravity than cast iron, so aluminum blocks are much lighter while meeting strength requirements. A lighter engine can positively impact the vehicle's weight distribution, and the overall vehicle mass is also reduced. In this aspect, aluminum blocks have an advantage. 2. Volume: For the same reason, due to aluminum's lower specific gravity, the structural strength per unit volume of aluminum is less than that of cast iron. Therefore, aluminum blocks usually have a larger volume. This makes the entire engine more compact and smaller in size, which is harder to achieve with aluminum blocks. In this aspect, cast iron blocks have an advantage. 3. Corrosion Resistance and Strength: Aluminum easily reacts chemically with water produced during combustion, making its corrosion resistance inferior to that of cast iron blocks. This is especially true for turbocharged engines with higher temperatures and pressures. The high modification limits of cast iron blocks are also well-known. It's quite difficult to achieve this with aluminum blocks. In this aspect, cast iron blocks have an advantage. 4. Cost: Naturally, aluminum blocks are more expensive. In this aspect, cast iron blocks have an advantage.