Light material with high Young's Modulus

[DiscipleofScience]

Dear All

Would you have any suggestions for a material with high Youngs modulus but is relatively light, mild steel has 210GPa but is roughly 7850kg/m3 - I suppose I am into Carbon Fibre territory?

I need to keep the CSA fairly small.

regards

John

 

[cloa]

Berrylium.
Silicon Carbide.
Is this homework?

 

[DiscipleofScience]

hehe no, it is for work,

 

[MintJulep]

If you could put numbers to "high" and "relatively light" you might actually get a useful suggestion.

 

[btrueblood]

From my old materials binder, the top materials in a list ordered by "specific stiffness" (E/rho)are: SiC, Boron, BC (boron carbide), then graphite-epoxy composites, beryllium, beryllia, then columbium (now called Niobium I think). Surprisingly, gold comes up pretty high on the list, better than aluminum or steel. Diamond would top the list today, still. Wikipedia gives a list of materials ordered by specific stiffness. You could probably build your own by downloading data from matweb.com.

 

[CoryPad]

Gold is terrible, high mass density (19 300 kg/m³, which is two and half times more than steel) and low elastic modulus (78 GPa, which is less than half of steel).

 

[DiscipleofScience]

hi MintJulep, I am lookihg for say a higher Young's modulus than steel as that will reduce the CSA, weight not so important.

The materials being listed are probably too exotic for our use.

Which is the best steel which is in general use?

 

[MintJulep]

The steel alloys with chromium and molybdenum are probably the stiffest.

However perhaps you should describe what you need to accomplish, rather than what you think you need. It seems likely that you are looking at the wrong material property for whatever problem you are trying to solve.

 

[btrueblood]

Yup, shoulda checked that entry. Figures that a materials engineer wrote that table...

 

[unclesyd]

Not knowing the end use you may want to consider a ceramic
specially the PSZ material. I would look especially at the PSZy material. There are other ceramics than may work. The weight problem could be mitigated by using cylinders.
There are some metal foams that can be made stiffer than steel
We use a lot of Sapphire rods for guides for coining metal. We also have all types of ceramic guides for fiber production.

http://www.mkt-intl.com/Sapphire_Materials/Sapphire_Properties.shtml

http://www.ergaerospace.com/index.html

 

[metman]

DiscipleofScience

different alloys of steel will all have the same Youngs Modulus for all practical purposes.

What is CSA?

 

[CoryPad]

Cross Sectional Area?

 

[jedward]

think foamed titanium with facesheets

 

[ginsoakedboy]

What is the application? Do you have a sketch you can share?

Try to provide some information related to your application that will get more meaningful responses. For example, loads (static, dynamic), potential failure modes, environment, temperatures range, applicable codes and standards, expected service life, quantities required (10 or 10,000?), consequences of failure (health, safety, environment, economic), budgetary constraints, design, analysis and testing resources at your disposal... and so on. I hope you get the idea.

 

[racookpe1978]

You gotta love any problem where the solution begins by including a list of materials including gold, niobium, diamonds, carbon fiber, and sapphires.....