What are the best lightweight materials for small wheel rims?

[oldunion]

I am looking to make some small wheel rims (about 6-8 inches). I know there are currently rims made of aluminum and magnesium. I know steel would work, but what would be some light weight alternatives. I know of titanium, carbon steel maybe?, steel. I am looking for the strongest, lightest, and cheapest material that can be cnc machined.

This is for a motor scooter, 62 cc's capable of 50+mph utilizing 10 inch pneumatic tires. It has two ball bearings that fit on the end and the axle is magnesium i think.

 

[brewnog]

Strongest, lightest and cheapest is a tall order, you need to weigh up what characteristics will give you the biggest benefits.

 

[Astronuc]

One should look at the peak stress and nominal cyclical stress level, then pick a material with an appropriate yield stress, toughness, fatigue strength and strength-to-weight ratio (one can take advantage of high strength to weight ratio and make a thicker section which reduces stress).

Then consider cost per unit mass of the material.

One good source of general information is the ASM International's journal, "Advanced Materials & Processes", which is often available in good technical libraries. There is usually specific volumes devoted to materials in both automotive and aerospace applications.

For your application, 'mag wheels' would seem appropriate. However consider:

http://www.sromagazine.com/paris/dictionary/sro-dicm.htm#MagWheel

http://www.sromagazine.com/paris/dictionary/sro-dica.htm#AlloyWheel

and

http://groups.msn.com/OldsmobileLovers-2/tipsandtrix.msnw?action=get_message&mview=1&ID_Message=1332

 

[brd]

nylon scooter rims

I am looking to make some small wheel rims (about 6-8 inches). I know there are currently rims made of aluminum and magnesium. I know steel would work, but what would be some light weight alternatives. I know of titanium, carbon steel maybe?, steel. I am looking for the strongest, lightest, and cheapest material that can be cnc machined.

This is for a motor scooter, 62 cc's capable of 50+mph utilizing 10 inch pneumatic tires. It has two ball bearings that fit on the end and the axle is magnesium i think.

The wheels could be manufactured from a certain grade of nylon. This material is not very easy to machine!