+- ask aluminium Forum (https://www.askaluminium.com)
+-- Forum: My Category (https://www.askaluminium.com/Forum-My-Category)
+--- Forum: aluminium faq (https://www.askaluminium.com/Forum-aluminium-faq)
+--- Thread: What if I use an aluminum alloy to make a cylinder liner? (/Thread-What-if-I-use-an-aluminum-alloy-to-make-a-cylinder-liner)
What if I use an aluminum alloy to make a cylinder liner? - Tyeshacon - 12-06-2018
It has been Tried but is Generally Held to be ONLY Partially Successful !!!! Aluminium is GREAT for Pistons but NOT so Good for Cylinder Liners !!!!! .First Let’s LOOK at Why we Use Liners in the First Place !!!!!
Ordinary Grey Cast Iron was Very Popular as a Cylinder Barrel Material in the First Half of the TWENTIETH Century as it was Strong, Cheap and Easy to Cast !
But it’s Heat Capacity was High and it’s Thermal Conductivity Rather Poor so Engines Used to Run rather Hot !! Couple that with the Fact that Iron Castings could be Porous and it Becomes Obvious that Whilst Cast Iron was “Adequate” for Cylinder Barrels it was NOT Ideal !!!!
Aluminium whilst More Expensive than Cast Iron is Both Lighter and Far More Conductive than Cast Iron so is a Natural Candidate for a Cylinder Barrel but it’s a Bit on the Soft Side and those Cast Iron Piston Rings are Pretty Hard So WEAR becomes a Problem !!!!! So Put a Relatively THIN Liner in made from something Harder than Aluminium and you Have the Best of BOTH Worlds a Hardwearing Liner with an Outer Casing of Aluminium to Conduct the Heat away !!!!!
Aluminium Cylinders with Hard Chromed Bores have been Tried and they Work !!!!! But if they WEAR, which of Course they DO Eventually it is Practically IMPOSSIBLE to have them Re-Bored !!!!!
RE: What if I use an aluminum alloy to make a cylinder liner? - Keganhirl - 12-06-2018
and what if you do?
its done all the time.
but the expense of the nikasil plating or other surfacing treatment required really makes it an expensive prospect.
and if the engine was designed for cast iron liners… then you have expansion contraction to deal with and the subsequent leakage, as well as finding rings that are compatible with the surfacing uses.
not bothering to chrome plate or nikasil?
then it will run for about five minutes before the liner is so worn out it needs replacing… along with all the bearings that just filled up with superfinely ground aluminium….
doesnt really seem worthwhile.