Alloy wheels query: Relation between number of spokes & wheel strength?

Could it be said that an alloy with merely three spokes is as strong as an alloy with 10 spokes?

BHPian adasisthefuture recently shared this with other enthusiasts.

There is hardly any discussion on this anywhere on the internet.

Every premium car and for that matter every top-of-the-line model of a mid-range car comes with alloy wheels. It is well settled now that alloys are much weaker in strength compared to steel wheels. However, how important role the number of spokes in an alloy plays with regard to the strength and durability of the alloy is debatable.

The spokes play an important role with regard to connecting the rim to the plate and therefore it is highly debatable whether the number of spokes would result in a stronger alloy.

Spokes in an alloy range from three to more than ten. Could it be said that an alloy with merely three spokes is as strong as an alloy with 10 spokes in terms of giving overall support to the RIM?

Also, whether an alloy with more spokes better at handling the impacts of pothole-ridden Indian roads compared to ones with lesser spokes?

Further, it would be interesting to study the implications of the number of spokes in low vs. high-profile tyres.

Views and real-life experiences of knowledgeable members of this forum are requested.

Here's what BHPian v1p3r had to say on the matter:

How is this well settled? The opposite is true - alloys are far stronger than pressed steel wheels, ceteris paribus.

This whole question is a non-issue. There is no relationship between the two that you can empirically state. Each alloy wheel is designed based on use, load factors, and metallurgical composition. Each such design will undergo rigorous FEA, followed by both destructive and non-destructive testing. Without this, there is no DoT or JIL or DIN certification possible. All things being considered, an alloy wheel is ALWAYS going to be better than a pressed steel wheel.

Source: automotive and motorsport engineer with real-world experience.

Here's what BHPian PaddleShifter had to say on the matter:

The strength of an alloy wheel depends on a variety of factors:

1. Forged vs. cast wheels- forged are considered better.
2. Design: See this thread/post regarding Mahindra floral design alloys breaking. The post linked below highlights a potential design flaw. The discussion concludes that a particular batch. I have seen SUVs with aftermarket 5 spoke alloys doing fine whereas this Mahindra alloys were breaking off completely.
3. Profile: Low-profile tyres will put more stress on the alloy wheels.

More spokes will make an alloy heavier which will affect their performance so the spokes on alloys need to be thinner as their number increases. e.g. the horseshoe design alloys from a FIAT Punto weigh as much as 1.5 times compared to a steel rim of the same size (15”) from Linea (Punto had 14” steel rims so compared with Linea steel rims).

Here's what BHPian SmartCat had to say on the matter:

I think it is like slices of Pizza. Whether you have 3 slices or 8 slices, the overall portion remains the same - it is just that the individual slices are smaller/bigger.

Similarly, when it comes to alloys, 5-spoke alloys will have wider spokes and 8-spoke or 12-spoke alloys will have slimmer spokes, but the total amount of metal alloy in the spokes will be nearly equal (for the same manufacturer/wheel size/quality models).

For the pizza logic to hold, all three examples:

• Should be made by the same manufacturer
• Should have the same wheel size
• Should have the exact same alloy composition

The last one is always an unknown. You can't figure this out by looking at the brochure or marketing material. Both can be marketed as "magnesium alloy", but they might have other elements like nickel/aluminium etc. and that % might be different for each model.

So the Pizza example just gives a theoretical Material Science point of view

Check out BHPian comments for more insights and information.