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I was thinking about titanium the other day and the benefits it has for cars. I thought through all of the existing products and thought about what else it could be used for. Would it be feasible and worthwhile to have titanium engine internals (i.e. pistons, rods, crank)? I mean they would be lighter and stronger than any other internals right? I know it would be extremely expensive, but is it possible?
 

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One word - adamantium.
 

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I was thinking about titanium the other day and the benefits it has for cars. I thought through all of the existing products and thought about what else it could be used for. Would it be feasible and worthwhile to have titanium engine internals (i.e. pistons, rods, crank)? I mean they would be lighter and stronger than any other internals right? I know it would be extremely expensive, but is it possible?
Ah, great minds think alike :cheers:

I've wondered the same thing. I think the real question is cost/benefit analysis. There's no arguing about whether or not Ti would be better, but is it worth it? The cost of Ti internals would probably be anywhere from 30% to 60% more, depending on the part and machining tolerance. I know they already have Ti valves (http://z1auto.com/prodmore.asp?model=350z&cat=engine&prodid=921). Personally, I don't think it would be worth it to us "common" folk. Most likely, only professional race teams would benefit from the difference. Although I still think it would be cool to have, if money weren't an option. :shiftdrive:
 

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One word - MONEY.

The weight savings is there, the strength is there for certain applications, but spending big money if the gains are not really justified is just not worth it to me.
 

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Titanium is more expensive, but what would make it extremely expensive for engine parts is that it is very difficult to machine.

For the most part steel is harder and stronger than titanium. Also, I don't believe titanium can handle as high an operating temperature as steel.
 

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For a daily driven car? No. Titanium is, chemically speaking, an aggressive metal. It will gall unlike metals and alloys it comes into contact with. Greatly increasing friction and wear.

Titanium has been employed for internals in racing applications for years, mainly for connecting rods. But on the street, titanium’s use has been pretty much limited to low-wear parts such as valve spring retainers.

There are currently some exotic surface treatments that can be applied to titanium that would make it more suitable for engine internal use. Unfortunately those processes are a few years away and limited, at the present time, to government and aerospace operations.

Good Luck
Ronin Z
 

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Titanium is, chemically speaking, an aggressive metal. It will gall unlike metals and alloys it comes into contact with.
True, I forgot that it becomes chemically reactive at higher temperatures which would happen in an engine. :cheers:

Not chemically reactive in implants because that's lower temperature.
 

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Ti rods MAIN benifit is their significant reduction in weight, when compared to steel. They arent necessarily stronger, just lighter. Ti rod sets from Pauter are roughly $6000 vs. $1190 for a set of 4340 chromoly. Even drag racing teams, in high budget applications, decline to use these types of materials.
 

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Ti rods MAIN benifit is their significant reduction in weight, when compared to steel. They arent necessarily stronger, just lighter. Ti rod sets from Pauter are roughly $6000 vs. $1190 for a set of 4340 chromoly. Even drag racing teams, in high budget applications, decline to use these types of materials.
Ti is stronger. If a man who weighs 150 lbs can support the same weight as a man who weighs 300 lbs, the 150 lbs man is stronger because he can support more weight per unit of body mass. Put another way, if you made the Ti rod so that it had the same mass as the steel rod, it would be able to withstand more force, therefore, it's stronger. You make the rod able to withstand what it needs to, and you don't need as much mass with Ti as you do with steel in order to withstand some given force.*

*in general
 

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Ti is stronger. If a man who weighs 150 lbs can support the same weight as a man who weighs 300 lbs, the 150 lbs man is stronger because he can support more weight per unit of body mass. Put another way, if you made the Ti rod so that it had the same mass as the steel rod, it would be able to withstand more force, therefore, it's stronger. You make the rod able to withstand what it needs to, and you don't need as much mass with Ti as you do with steel in order to withstand some given force.*

*in general
You are correct...ASSUMING THE SAME MASS. The whole point of using Ti, is you can use less material and less weight, for a given application. So you have a rod that is just as strong as steel (or close), but weights less.
 

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Alot of Top Fuel dragsters run Titanium rods.I had one from a TOp Fuel dragster and it looked as if it should weigh 25lbs but was lighter than a stock Z rod.. The cost on one of those rods is about $1700, EACH..
 

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You are correct...ASSUMING THE SAME MASS. The whole point of using Ti, is you can use less material and less weight, for a given application. So you have a rod that is just as strong as steel (or close), but weights less.
I get it now. I was saying Ti is stronger than steel...in general. You were specifically saying the Ti connecting rods are just lighter but not really any stronger than forged steel ones. :cheers:
 

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Ti is stronger. If a man who weighs 150 lbs can support the same weight as a man who weighs 300 lbs, the 150 lbs man is stronger because he can support more weight per unit of body mass. Put another way, if you made the Ti rod so that it had the same mass as the steel rod, it would be able to withstand more force, therefore, it's stronger. You make the rod able to withstand what it needs to, and you don't need as much mass with Ti as you do with steel in order to withstand some given force.*

*in general
What you are saying is true. However, the entire engineering world calculates strenght in something like psi, which is independent of the materials density. So, they would take 2 pieces that are the same GEOMETRY to see which one is stronger. I think you understand the concept, but you are incorrect in speaking strength in terms of mass.
 

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What you are saying is true. However, the entire engineering world calculates strenght in something like psi, which is independent of the materials density. So, they would take 2 pieces that are the same GEOMETRY to see which one is stronger. I think you understand the concept, but you are incorrect in speaking strength in terms of mass.
First, visit this site: http://en.wikipedia.org/wiki/Tensile_strength (note the charts with desity values near the bottom of the page)

Any material used with any given geometry will have some given density. That is factored into the overall calculation as to a materials strength. In other words, density is a property of the material that affects strength. Mass is directly related to desity with d=m/v. Therefore, the strength of any material IS dependant upon it's mass.
 

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First, visit this site: http://en.wikipedia.org/wiki/Tensile_strength (note the charts with desity values near the bottom of the page)

Any material used with any given geometry will have some given density. That is factored into the overall calculation as to a materials strength. In other words, density is a property of the material that affects strength. Mass is directly related to desity with d=m/v. Therefore, the strength of any material IS dependant upon it's mass.
Yes, density is one of the things that affects strenght. However, it is NOT factored into the overall calculation of a material's strength. The yield and tensile strengths are in units of MPa. That is the metric equivalent of psi (pounds per square inch). If it has a tensile strenght of 100,000 psi, that means you can put 100,000lb of force on a part that has a 1 inch square cross section. This is independent of density. :)
 

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density is not directly proportional to static strength.

mercury is more dense that steel :) I doubt you will want mercury connecting rods.
 

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Yes, density is one of the things that affects strenght. However, it is NOT factored into the overall calculation of a material's strength. The yield and tensile strengths are in units of MPa. That is the metric equivalent of psi (pounds per square inch). If it has a tensile strenght of 100,000 psi, that means you can put 100,000lb of force on a part that has a 1 inch square cross section. This is independent of density. :)
Really? So if I have a 1 inch cross section of steel with a density of 1 g / cm^3, and a 1 inch cross section of steel with a density of 100 g / cm^3, they will both yield the same tensile strength?
 

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Really? So if I have a 1 inch cross section of steel with a density of 1 g / cm^3, and a 1 inch cross section of steel with a density of 100 g / cm^3, they will both yield the same tensile strength?
Absolutely not! And, you can actually have 2 pieces of steel 1 g/cm^3 and 1" cross section, and they can be IDENTICAL alloys and still have different tensile strengths.... How? because of different tempereing (hardening) processes. That's where they cook the steel at different temperatures then quench it, FYI. Now how important do you think density is??? :)
 
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