Beryllium in Automotive Applications

[Runge_Kutta]

First, the downside - Berylliosis

http://www.healthatoz.com/healthatoz/Atoz/ency/berylliosis.jsp
http://www.eh.doe.gov/health/beryllium/communicating.pdf

Now, the upside

From ( www.tsgc.utexas.edu/archive/subsystems/structures.pdf Pages 10-15)

=================
Beryllium

With a density approximately 60% of aluminum and a stiffness to weight ratio six
times better than aluminum or titanium, this material has many potential
applications. Being stiffer than other materials it can be useful in avoiding resonant
frequencies that may occur between a satellite and its booster during launch. It is
non-magnetic, has a high elastic modulus (44 Msi), and a high yield strength. Using
beryllium instead of aluminum can reduce weight significantly, and its high
thermal conductivity makes it an excellent choice for components that will conduct
heat. It is also non-reactive with hydrogen.

However, beryllium is extremely anisotropic and sensitive to damage, and is twice
as brittle as aluminum. Its relatively low fracture toughness at cryogenic
temperatures is a potential drawback, but development of beryllium-aluminum
alloys may improve this. It also needs special facilities and tools for machining due
to the toxicity of its dust, and is thus very expensive.
=================

From ( http://www.ccdott.org/hss_volume2/07_loads,_materials_&_structures.pdf See Table 1)

=================
Beryllium-aluminum alloys containing greater than 60 percent (by weight)
beryllium are favorable materials for applications that require light weight and high
stiffness. These alloys have 22 percent lower density than aluminum with three times the
elastic modulus and a 40 percent lower coefficient of thermal expansion. Some
aluminum-beryllium alloys have been developed for aerospace applications. The
AlBeMet series of alloys was initially selected for a folding fin on the SR-71 Blackbird.
The properties of some of the beryllium-aluminum alloys are presented in Table 2.
AlBemet 162 is a promising alloy with a high cycle fatigue limit of 10 million
cycles at 30.5 ksi. It is immune to stress-corrosion cracking at 90 percent of
yield stress in saltwater at 65 degrees C for 169 hours and in salt at 315 degrees
C for 100 hours.
=================

Here are some properties:

=================
http://www.geocities.com/pganio/materials.html (AM 162 makes titanium look cheap!!)
http://www.matweb.com/search/SpecificMaterial.asp?bassnum=NBB002
http://www.asminternational.org/Tem...ate=Ecommerce/FileDisplay.cfm&file=ACF7E2.pdf
=================

So, where is beryllium used?

=================
http://www.pureluckdesign.com/ferrari/f1engine/ (Pistons)
http://www.clevelandclinicmeded.com/diseasemanagement/pulmonary/occlung/table1.htm
http://www.thalesgroup-optronics.com/pdf/Beryllium.pdf
http://nautilus.fis.uc.pt/st2.5/scenes-e/elem/e00410.html
http://www.focal.tm.fr/gb/instal/images/cahiertekgube.pdf
http://www.reade.com/ezine/vol1issue6/reade0106_en_4.shtml
http://www.jobwerx.com/news/Archives/aerospace_materials_advances_news_id_102703.html (AM 140)
=================

The primary American producer of Beryllium appears to be Brush-Wellman

http://www.berylliumproducts.com/web/bpdweb.nsf

For weight loss in Corvette applications, one is probably mostly interested
in alloys of beryllium and aluminum. The alloy which is 62% beryllium and
38% aluminum looks like a good choice ALuminumBErylliumMETAL162 = AlBeMet162

http://www.reade.com/Products/Alloys/aluminum_beryllium_alloy_al_be.html

One can also apply beryllium-aluminum alloys to engine bearings:

===========================
http://patft.uspto.gov/netacgi/nph-...0&d=PTXT&p=1&S1=6308680&OS=6308680&RS=6308680

GM Patent, Engine block crankshaft bearings, 6,308,680

An internal combustion engine comprises an aluminum alloy engine block housing
pistons in cylinders and having a lower face including an upper semi-circular
bearing surface. A lower bearing support has a lower semi-circular bearing
surface to complement the upper semi-circular bearing surface in the engine
block to define a crankshaft bore to rotatably support a ferrous crankshaft.
The lower bearing support is formed of a single beryllium-aluminum alloy having
a coefficient of thermal expansion comparable to the ferrous crankshaft to
promote a consistent clearance between the lower bearing support and the
crankshaft. Such a beryllium-aluminum alloy may be comprised of approximately
60-65% by weight beryllium and the balance is aluminum.
===========================

Here's an informative patent on beryllium-aluminum alloys

===========================
6,312,534 High strength cast aluminum-beryllium alloys containing magnesium

http://patft.uspto.gov/netacgi/nph-...1=AND&d=ptxt&s1=6312534&OS=6312534&RS=6312534
===========================

Also:
6,656,421 Aluminum-beryllium-silicon based alloy

While there are also beryllium-copper alloys, I doubt they have much
application in the mechanical part of a Corvette except the valve
seat in the heads.

http://www.brushwellman.com/alloy/tech_lit/GuideToCopperBeryllium.pdf

Here's some random stuff:

http://minerals.usgs.gov/minerals/pubs/commodity/beryllium/berylmcs96.pdf
http://minerals.usgs.gov/minerals/pubs/commodity/beryllium/100495.pdf ($275/pound for Be powderin 1995)
http://minerals.usgs.gov/minerals/pubs/commodity/beryllium/100498.pdf ($385/pound for Be powderin 1998)

Compare Beryllium-Aluminum (AM162) to traditional Aluminum-Silicon alloys
used for pistons. The LS1/LS6 and presumably LS2/LS7 use a Mahle alloy
M142. Here's something relatively close.

http://www.spba.net/pdf/alsi356.pdf

 

[Runge_Kutta]

Just in front of titanium alloys, this 62%Be-38%Al (AlBeMet162)
is my favorite alloy. I don't know for sure but AlBeMet162
is probably about $200/pound. That immediately means only very small
parts will ever use it in cars. The only place that makes sense is
in pistons. However, I'd love to see the Corvette team do a quick
computer study of an optimized AlBeMet162 frame for C6 (or C7) to
see how light one can make it while retaining all other desired
properties.

LS1 pistons are made of an aluminum-silicon alloy (Mahle 142) and
weigh 434 grams (0.96 pounds). Mahle 124 is 12% Silicon. Assuming
Mahle 142 is close to Mahle 124, it's interesting to compare the
LS1 piston material to AlBeMet162.

( http://techtran.msfc.nasa.gov/tech_ops/nasa388alloy.pdf )


(AlBeMet162)[Mahle 124]
=======================

Density
(2.071 g/cc)[2.73 g/cc]

Modulus of Elasticity
(193 GPa)[84.1 GPa]

Ultimate Tensile Strength
(435 MPa)

Yield Tensile Strength
(321 MPa)[228 MPa]

Thermal Conductivity
(210 W/m-K)[122 W/m-K]

Linear Coeff. of Thermal Expansion (linear)
(13.91 µm/m-°C) [19.6 µm/m-°C]


It seems to me that if you simply made a material switch and
made whatever other design adjustments were needed, the new
piston would be 105 grams lighter (329 grams) or 25% lighter.
It also seems to me that since the material is stronger, one
could further reduce weight. Besides this, the piston changes
size less with temperature than the original piston.

Also, see

http://techtran.msfc.nasa.gov/tech_ops/nasa398alloy.pdf

 

[Edmond]

relatively low fracture toughness at cryogenic temperatures

How cold is cryogenic temperatures? Is there an everyday example where a car would be subject to cryogenic temperatures?

 

[Runge_Kutta]

I think it loosely refers to temperatures at or below -235 deg. F.

I don't think this is an automotive issue. The most serious issue is
cost. It appears to be over 10 times more expensive than titanium!!
In 2004, beryllium powder was $375/pound!!! Someone once built a
bicycle frame of of this stuff. The company was called "Beyond Beryllium
Fabrications." Trek may have also done this.


http://www.sierraclub.org/sierra/199711/lol.asp
http://www.mdatechnology.net/techsearch.asp?articleid=403

BEYOND BERYLLIUM FABRICATIONS 408/293-8095 ( ??????????????????????)

I think they've long since gone belly up.

 

[Runge_Kutta]

OK, let's look at AlBeMet162 versus the aluminum alloy used in the Z06
frame; AA 5754 (I think). The new Z06 frame is said to be 137 pounds
lighter than the C6 steel frame according to Dana. Depending on how
you define what the "frame" is, it sounds like the AA5754 frame is
about 300 pounds. Quickly, AlBeMet162 is roughly 75% of the density
of AA5754 so that one might guess that the AlBeMet162 frame would
weigh 225 pounds. At 62% beryllium, that's 139.5 pounds of beryllium
at 375$ per pound or $52312.50 for frame materials alone (2004 price for
Be powder).

From:

http://www.autoaluminum.org/downloads/corpub.pdf ( Appendix A)
http://europa.eu.int/comm/research/transport/pdf/turin1010_0930_en.pdf ( page 5 )
http://www.peregrinecorp.com/peregrine/compare.htm
http://msl1.mit.edu/msl/meeting_04192001/prz_pdf/constantine.pdf
http://www.climaxresearch.com/MICRO...TIES OF HYDROFORMED AL ALLOYS 6063 & 5754.PDF

(AlBeMet162)[Aluminum Alloy 5754]
=======================

Density
(2.071 g/cc)[2.69 g/cc]

Modulus of Elasticity
(193 GPa)[71 GPa]

Ultimate Tensile Strength
(435 MPa)[267 MPa]

Yield Tensile Strength
(321 MPa)[152 MPa]

Yield Tensile Strength required to sustain 10^7 cycles
(145 MPa)[135 MPa]

Thermal Conductivity
(210 W/m-K)[134 W/m-K]

Linear Coeff. of Thermal Expansion (linear)
(13.91 µm/m-°C) [23.6 µm/m-°C]

While I am no structural engineer, if you design to similar maximum
strengths over 10^7 cycles, the AlBeMet162 will be much stiffer and
75% of the weight (loss of 75 pounds). If you can redesign the frame
around similar fatigue limits but triple the stiffness, you might
be able to beat the 75 pound weight loss. Even at 100 pounds, Dave
Hill's often quoted metric of $10/pound allows $1000 for this frame.
Oh well!! Don't hold your breath for this one!!

-----

Misc. Beryllium:
================

http://www.du.edu/~jcalvert/phys/beryl.htm
http://www.brushwellman.com/alloy/markets/auto.asp
http://ehp.niehs.nih.gov/roc/tenth/profiles/s022bery.pdf
http://minerals.usgs.gov/minerals/pubs/commodity/beryllium/berylmcs04.pdf
http://minerals.usgs.gov/minerals/pubs/commodity/beryllium/berylmcs05.pdf

 

[Edmond]

$52312.50 for frame materials alone

That's more than the price of the C6!

 

[ROCKETBLOCK]

Thanks for the information. I enjoy reading about this and knowing a little about it to make comparisons to other options (metal or non-metal) for components in automobiles. Very interesting future technologies and materials will cross paths in the future. Sadly, it may be long after the era of the muscle car is only a distant memory.

 

[Runge_Kutta]

http://ntp.niehs.nih.gov/ntp/roc/toc11.html

click on

"Beryllium and Beryllium Compounds"