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A high-strength aluminum cylinder block manufactured using a new production process, ASCT (Advanced Semisolid Casting Technology) has been adopted for the newly developed 2.2L 4-cylinder i-CTDi (Intelligent Common rail Turbo Diesel Injection) diesel engine fitted in the new Accord to be marketed in Europe. In the production process, a semisolid aluminum is used during high-pressure die-casting. In addition, newly developed pressure resistant sand cores are used to mold the closed deck. Heat treatment is conducted to ensure a high level of materials strength. To respond to the high load on the crankshaft journal, die-cast aluminum lower block with cast iron bearing caps inserts are employed. Adopting the dummy head honing to reduce bore deformation and offset cylinders have enabled the achievement a lightweight and compact cylinder configuration matched to the high combustion pressure of the latest diesel engines, while maintaining a high level of quietness.

High dimensional accuracy of die-cast part enables net-shape forming or machining reduction. That is one of the strategies to get sharp cost cutting in any aluminum die-casting applications, including engine and power train parts of automobile. However, it had been difficult to specify the key technology for dimensional stability. This project has digitized relation between manufacturing conditions and dimensional stability by a dynamic analysis, based on transferability theory of Quality Engineering1). The most important factor has been die-cast part's temperature at ejection, taking error of mass production in account. If we kept the temperature constant, we could die-cast a part with equivalent accuracy to a die.