Magnesium allow for lighter car engines.

[Fr3AkAzOiD]

Been checking up on this from time to time so figured I'd make a post on it and see what everyone thinks.

Even though cars seem to keep getting heavier and heavier the auto industry is trying new things to cut weight down.

Over about the last ten years they have been working on developing magnesium allows that can be used to replace steel and aluminium parts in car engines.
One paper I read shows a 29% weight reduction in the block assembly, oil pan, and front cover on a V6 when using magnesium alloys instead of aluminium.
It doesn't look like they have found the perfect alloy yet but I can see this trickling into the car market in several years.

First site I found was on the magnesium alloy AM-SC1 and it was used to make a three cylinder turbo diesel engine that was tested for two years and 65,000km in a Volkswagen Lupo with promising results.

Lighter motor cars for the 21st century (Solution)
and
AM-SC1, A Magnesium Alloy Developed for Automotive Powertrain Components by Advanced Magnesium Techn


This paper shows some of the testing done on the AM-HP2 magnesium alloy and it being compared against several magnesium alloys for various properties.

http://www.am-technologies.com.au/pd...plications.pdf

This last one is a presentation done last September for the Big 3 US auto makers. It has data obtained from tests with a magnesium alloy build of a
2.5L V6. Though there were some areas where the testing didn't go so well the paper seems to convey confidence that the problems can be engineered out given time.

http://www1.eere.energy.gov/vehicles...r10_powell.pdf

[Piwoslaw]

Thanks for gathering that info, Fr3Ak.

How does mining and producing magnesium compare to steel and aluminum? I mean, how scarce/plentiful is it, is it evenly distributed or are most of the resourses in the hands of 1-3 countries, how much energy and what other chemicals must be put into processing, what kind of pollution is produced, etc.? I've read that aluminum helps save energy because of it's reduced weight (compared to steel and iron), but getting it just plain sucks from the global/environmental point of view. If magnesium alloys are easier (energy-wise) to make, then that would be awesome.

[Fr3AkAzOiD]

Did a quick Google search, figures China would make the most.
I'm taking a wild stab that even if there are environmentaly friendly ways of getting it that China isn't paying the extra $ to mine it right.

Rank Country Production (Metric tons)
1 China 627,000
2 Russian Federation 37,000
3 Israel 25,000
4 Kazakhstan 21,000
5 Brazil 18,000
6 Canada 16,300
7 Ukraine 2,500
8 Serbia 1,500

Though we are about in the same situation for Aluminium.
Rank Country Production (Thousand Metric tons)
1 China 12,600
2 Russian Federation 3,955.42
3 Canada 3,082.63
4 United States 2,554
5 Australia 1,960

Avg cost of each.


A quick Google couldn't find any info specific to enviromental impacts of mining Magnesium.
But then again my daughter woke up from her nap so I didn't put much time into looking.

[Ryland]

A big part of the problem is that they are trying to make V8 engines, VW has used magnesium starting back in the '60s.

[UFO]

Originally Posted by Ryland

A big part of the problem is that they are trying to make V8 engines, VW has used magnesium starting back in the '60s.

Weren't the original VW air cooled Beetle engine cases made of magnesium alloys in the 40s??

[Ryland]

Originally Posted by UFO

Weren't the original VW air cooled Beetle engine cases made of magnesium alloys in the 40s??

Maybe it was as early as the '40's, a big part of the reason that they used magnesium is that it doesn't have the same thermal expansion that aluminum does, so with an air cooled engine that tends to run hotter having your crank case expand would lower your compression as it heated up.

[some_other_dave]

They ran mag cases on the aircooled VWs for quite a long while. I don't remember when they started or stopped, but they reverted to aluminum because magnesium isn't as strong. Porsche had problems with their engines as well; they changed from sand-cast Al to die-cast Mg in the mid-60s, and by the time they were making 2.7 liter engines in the mid-70s the cases were failing at a (relatively) alarming rate. So in 78 they went back to Al.

Lots of non-structural parts for many cars are made of Mg as well; I am most familiar with the aircooled VW and Porsche stuff. For a long time the transmission cases were made of Mg, but again the strength did become an issue after a certain power level. On the Type IV VWs, the fan shroud was Mg while the crankcase and heads were Al.

The strength has been a problem with structural mag parts for a long time. With the current "need" for power and reliability, there will be some work needed to make Mg parts pracitcal.

-soD

[RobertSmalls]

The Honda Insight has a Mg oil pan, which is also integral to the structure of the block. It works.

It's a question of how much money you want to spend on getting better FE, and whether this is sufficiently low-hanging fruit at the moment.

[Ryland]

Would't it be better just to skip the v8 engine design and put a turbo on an inline 4? you get the low weight, high power when you need it, it takes up less space, the only draw back is you don't get to put the V-8 logo on the back of the vehicle.

[RobertSmalls]

Four? Wastrel. :P

And if you must have a four, you could have a Mg four.