Talk:Magnesium alloy wheel

Most modern "mag wheels" are actually aluminum. Big chunks of magnesium were very unpopular with aluminum recyclers, who had to run an acid stream on the wheels going by to detect the magnesium ones. --Nagle 04:50, 18 March 2006 (UTC)[reply]

Ok, I added that info to the article, although without the details on recycling techniques. Thanks. StuRat 00:34, 19 March 2006 (UTC)[reply]

Stub tag[edit]

I see that this page has a stub tag. I don't know much (read anything) about motor wheels. I have studied alloys at school but cannot contribute here. Please StuRat, I respect you. You remind me of Socrates (I don't personally know neither of you). So please, either expand the article or remove the tag. It does not look good this way. Kushal one 22:35, 22 March 2006 (UTC)[reply]

I'd like to expand it, but I'm not an expert on car racing, either. It seems to need quite a bit more info before the stub tag can be removed, such as:

Which forms of autoracing have used mag wheels ? NASCAR ? Formula 1 ? Funny car drag racing ?

When were they used ?

Which magnesium alloys are used ?

Since they are flammable, what are the legal restrictions on their use for street vehicles ?

StuRat 23:28, 22 March 2006 (UTC)[reply]

Let the stub tag be there so that persons interested may come and expand the contents. --Bhadani 14:19, 23 March 2006 (UTC)[reply]

Magnesium wheels ARE NOT FLAMMABLE. Magnesium meets all requirements of flammabilty resistance standards. Magnesium wheels are used in Formula One racing cars. The wheels are produced by one-step hot forging from magnesium alloys ZK60 and MA-14 (Russian variation of ZK60).

There is no restriction to use magnesium wheels in street cars. However, the price of magnesium forged wheels are too high for automotive industry at the present time. Cast magnesium disks are used in motocycle wheels. Some of military and transportation aircrafts and helicopters have sand-cast magnesium wheels. --Westend 13:25, 28 April 2006 (UTC)[reply]

You can go ahead and update the article with that info. However, since magnesium itself is flammable, some explanation is needed as to why mag wheels aren't. Were any previous versions flammable ? StuRat 22:02, 28 April 2006 (UTC)[reply]

First of all magnesium is not self-ignited material. In order to ignite magnesium you should melt it. However, magnesium has very good thermo-conductivity, therefore so massive part like automotive wheel (about 8 kg) is not easy to melt. Magnesium can be easy ignited in form of powder, small chips or thin wire. However, also other construction metals, such as aluminum and titanium are flammable in form of powder and chips.

Does anybody worry about flammability of aluminum cookware? Sure not!

Why people are so worry about flammability of magnesium? The answer is very simple. Some of us still remember magnesium photo flash. Other people probably remember ignition of magnesium from chemistry lessons in school. In both cases, magnesium powder or small pieces of magnesium foil were used.

I am very involved in world magnesium industry. However, I do not know at least one case when magnesium component in a car or in an aircraft burnt. Vehicle includes a lot of other material with lower ignition point than magnesium.

Every new material in automotive and aerospace industry shall be tested by standard flammability tests. I do not know any case when magnesium did not meet requirements of the tests. Therefore, in professional point of view, magnesium is not flammable material.--Westend 09:10, 2 May 2006 (UTC)[reply]

I consulted a chemistry major, and he said that the problem with magnesium vs. aluminum is that magnesium oxide flakes off (like iron oxide, AKA rust), exposing the flammable metal underneath, while aluminum oxide forms a patina around the pure aluminum, which makes it nonflammable. Of course, this difference no longer applies if the elements are melted, as you've noted. StuRat 20:56, 2 May 2006 (UTC)[reply]

Your chemistry major is complete right. That is exactly a mechanism of ignition for bare magnesium.

However magnesium wheels are coated and at the present time we know how to make coating for improving of flammability resistance. It works in same way like patina on aluminum.

There is also another technique how to protect magnesium against ignition. Unfortunately this information is protected and I can not disclosure it here.

The main reason why we do not see magnesium wheels on every car is cost. The cheapest one costs about 380-450 USD.--Westend 14:53, 3 May 2006 (UTC)[reply]

The burn risk happens when grinding Magnesium alloy engine blocks. Happened to a friend. Polypipe Wrangler 23:06, 21 April 2007 (UTC)[reply]

Article needs a rewrite[edit]

Magnesium alloy wheels are cast from an alloy and are not forged. Alloys often behave in a superior way to the individual elements which form the alloy. "Mag rims" are very popular on street cars these days. In [[South Africa] there is a roaring trade in any recycled metal, with most of it being exported to China.Gregorydavid 15:50, 27 December 2006 (UTC)[reply]