Metal finishing Q&As since 1989

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Is Nikasil Successful for Diesel Cylinders?

I am writing to ask if there is good experience of using the Nikasil process for Diesel engine cylinders. I am thinking of an engine with a bore size of about 95 mm diameter and the engine will have high compression ratio and turbocharging so that the firing pressures and the piston side loads will be high, compared with gasoline engine operation, usually throttled. Also the thermal loading is quite high. Are there any special guidelines for the type of Nikasil processing and finishing best suited for an application like this?

It is assumed that the piston should be iron plated; is there an alternative or better solution, for an Al-alloy piston skirt, please? Would chrome ring facings be the most appropriate for such a case? Would anyone suggest a better approach than Nikasil for Al-alloy cylinder liners.

Finally, can Nikasil be used successfully with a ported liner in a 2-stroke diesel? Would the non-continuous oil film that results from the rings passing over the ports result in problems or serious wear?

Any experience relating to a Diesel application will be very gratefully received.

Rod Thomas
-Brighton, East Sussex, UK
2001