Cast steel
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Re: Cast steel
Far as I know, engine blocks are not cast from nodular iron--ductile iron, (nodules formed chemically by the metal alloy) or malleable iron (nodules formed by heat-treatment). The block casting is too complex. The thin sections cool too quickly, the thick sections cool too slowly. Nodular iron is used for smaller, simpler castings--connecting rods, crankshafts, steering knuckles, differential housings, etc.David Redszus wrote: ↑Tue Mar 14, 2023 12:03 amThe primary reason being that ductile cast iron is a superior material, compared to steel,Little Mouse wrote: ↑Sun Mar 12, 2023 9:20 pm I'm wondering why the OEMs or the aftermarket have not used cast steel to make cylinder block's or cylinder heads.
for cylinder blocks.
Ductile, or nodular cast iron has graphite nodules that provide a low friction coefficient
when run against steel pistons rings. It also has a very high tensile, high hardness, is easy
to cast accurately and...it is cheaper than steel.
https://en.wikipedia.org/wiki/Ductile_iron
https://en.wikipedia.org/wiki/Malleable_iron
The closest engine blocks get to "nodular" is Compacted Graphite.
Am I wrong?
Despite the fraudulent advertising of "cast steel" crankshafts, genuine steel is difficult to cast. "Cast steel" cranks are actually cast iron. Eagle finally admitted that their "cast steel" cranks have far too much carbon to classify as "steel", and GM has long acknowledged that "Armasteel" is pearlitic malleable iron--although I've heard folks claim it's melted-down WWII surplus steel armaments.
Last edited by Schurkey on Tue Mar 14, 2023 5:12 pm, edited 2 times in total.
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Re: Cast steel
David Redszus wrote: ↑Tue Mar 14, 2023 12:03 am Cylinder heads are made of aluminum alloys because it provides a high thermal transfer.
...and the molds are enormously easier/cheaper to make compared to molds for cast iron.
Re: Cast steel
Some aftermarket engine blocks are ductile iron.
You can tell from how it cuts, forming short chips rather than coarse dust.
You can tell from how it cuts, forming short chips rather than coarse dust.
Re: Cast steel
You are so right with this.Schurkey wrote: ↑Tue Mar 14, 2023 5:06 pmFar as I know, engine blocks are not cast from nodular iron--ductile iron, (nodules formed chemically by the metal alloy) or malleable iron (nodules formed by heat-treatment). The block casting is too complex. The thin sections cool too quickly, the thick sections cool too slowly. Nodular iron is used for smaller, simpler castings--connecting rods, crankshafts, steering knuckles, differential housings, etc.David Redszus wrote: ↑Tue Mar 14, 2023 12:03 amThe primary reason being that ductile cast iron is a superior material, compared to steel,Little Mouse wrote: ↑Sun Mar 12, 2023 9:20 pm I'm wondering why the OEMs or the aftermarket have not used cast steel to make cylinder block's or cylinder heads.
for cylinder blocks.
Ductile, or nodular cast iron has graphite nodules that provide a low friction coefficient
when run against steel pistons rings. It also has a very high tensile, high hardness, is easy
to cast accurately and...it is cheaper than steel.
https://en.wikipedia.org/wiki/Ductile_iron
https://en.wikipedia.org/wiki/Malleable_iron
The closest engine blocks get to "nodular" is Compacted Graphite.
Am I wrong?
Despite the fraudulent advertising of "cast steel" crankshafts, genuine steel is difficult to cast. "Cast steel" cranks are actually cast iron. Eagle finally admitted that their "cast steel" cranks have far too much carbon to classify as "steel", and GM has long acknowledged that "Armasteel" is pearlitic malleable iron--although I've heard folks claim it's melted-down WWII surplus steel armaments.
Re: Cast steel
I think you mean the 710 casting. The 567 and 645 are normalized weldments. Adding 1" in stroke to the 645 got us the fuel efficiency we needed to compete with GE. We gave up that 1" with the port window used in the 2 event / cycle engine. My design. Adding 1" gave us a 10% increase in power with no increase in fuel consumption.
Re: Cast steel
710 blocks are also fabricated from wrought steel maybe the odd forging toRAS wrote: ↑Tue Mar 21, 2023 12:37 amI think you mean the 710 casting. The 567 and 645 are normalized weldments. Adding 1" in stroke to the 645 got us the fuel efficiency we needed to compete with GE. We gave up that 1" with the port window used in the 2 event / cycle engine. My design. Adding 1" gave us a 10% increase in power with no increase in fuel consumption.