"We published a study not long ago on titanium-gold, a 1-to-1 ratio compound that was a magnetic material made from nonmagnetic elements."
What causes this?
Re: Ferrari Power Unit
Posted: 20 Feb 2018, 20:31
by godlameroso
High temperatures I guess. All sorts of wacky things happen at high frequency energy, you can turn cobalt into highly radioactive metal. Smelting alloys at high temperatures can have emergent properties, maybe it's as simple as the same reason NOx is produced during high combustion temperatures.
Tell me the alloy that you are thinking of for the pistons...
They go by different names depending on the supplier - I can't name any off the top of my head. I don't have any Mahle or FM catalogues at hand but the alloys I am talking about are low alloy (5% max or so ) powder metal steels Fe-Cu-C with trace Ni and Mo and ferritic/pearlitic structure. Normally they have some form of solid lubricant (since they are primarly used for valve seats) but of course those would not be needed in a piston.
Thermal conductivity is up to 50W/mK.
It says that endurance strength for Fe-Cu-C alloys is about 130 MPa at room temperature. By comparison one of Mahle's strongest piston Al alloys (Mahle 142) has between 90-130 MPa endurance strength at room temperature dropping to as low as 30-50 MPa at 350 °C. I haven't found high temperature Fe-Cu-C properties but I bet it won't decrease anywhere near as much as Al.
Bear in mind though it needs to be about 3 times stronger than Al to be viable..
Re: Ferrari Power Unit
Posted: 21 Feb 2018, 01:16
by godlameroso
I'm just waiting for the cars to run on knock once and for all.
How problematic is knock & detonation when the air-fuel charge is so lean and stratified? If the fuel does ignite prematurely it will be localized. I suspect detonation can be incorporated into regular operation and be rendered irrelevant. Maintaining separation of the fuel-air charge from non-combustion air (I'll call this NCA; maybe there's another established term) is the trick. NCA or delineated CC volumes will absorb/withstand detonation, ignition and pre-ignition of the fuel-air charge. Timing, inclusion or disclusion of those events is important but only for performance, not durability or catastrophic failure of the componentry (my guess).
Tell me the alloy that you are thinking of for the pistons...
They go by different names depending on the supplier - I can't name any off the top of my head. I don't have any Mahle or FM catalogues at hand but the alloys I am talking about are low alloy (5% max or so ) powder metal steels Fe-Cu-C with trace Ni and Mo and ferritic/pearlitic structure. Normally they have some form of solid lubricant (since they are primarly used for valve seats) but of course those would not be needed in a piston.
Thermal conductivity is up to 50W/mK.
It says that endurance strength for Fe-Cu-C alloys is about 130 MPa at room temperature. By comparison one of Mahle's strongest piston Al alloys (Mahle 142) has between 90-130 MPa endurance strength at room temperature dropping to as low as 30-50 MPa at 350 °C. I haven't found high temperature Fe-Cu-C properties but I bet it won't decrease anywhere near as much as Al.
Bear in mind though it needs to be about 3 times stronger than Al to be viable..
I was hoping to comparemanufacturing methods: sintered powder forged steel to wrought forged steel for mechanical properties and machinability.
Then the thermal properties material itself: sintered powder forged FeCu steel to Aluminum alloy to the wrought forged steel.
I wonder if there's a compressed air line hidden in that assembly somewhere. Otherwise, those arcs could like create a shock wave sufficient to move that small hinged plate. I'm not sure what they're getting at in the press release besides technobabble.
Re: Ferrari Power Unit
Posted: 21 Feb 2018, 02:09
by johnny comelately
It may be worthwhile having a look at flame ignition first hand, it is a fantastic effect.
They are relatively easy to make and when you play around with timing and mixtures then whip the head off and have a look, it is a different world of combustion.
And you may find page 71 in this link very interesting (Smokey Yunick) https://books.google.com.au/books?id=bf ... ts&f=false
I wonder if there's a compressed air line hidden in that assembly somewhere. Otherwise, those arcs could like create a shock wave sufficient to move that small hinged plate. I'm not sure what they're getting at in the press release besides technobabble.
They pump 1 atm for a total of 2 into the chamber and then discharge the plasma. The heat expands the air and pushes the plate.
I wonder if there's a compressed air line hidden in that assembly somewhere. Otherwise, those arcs could like create a shock wave sufficient to move that small hinged plate. I'm not sure what they're getting at in the press release besides technobabble.
They pump 1 atm for a total of 2 into the chamber and then discharge the plasma. The heat expands the air and pushes the plate.
A small lightning bolt will inevitably create a shock wave in a gaseous medium regardless of its internal pressure (within reason). I don't see what's unique about using sound waves, focused/exaggerated within a cylindrical container, to move a small pendulum.
