What are these rivet like fasteners?

This is a 203mm (~8 inches) rotor for a mountain bike. The outer is stainless and the inner is aluminum. The two are connected by 6 fasteners that look like big rivets. What are they, and where can I get some?

For context, I've been messing laser cutting parts and I thought this would be a nice easy project.

 

Sprocket Bolts?

 

They have a few names

cap nut, push nut, retainer nut. These might not be it and might be another name. They have some tolerances to push over a tube and engage in the shaft / tube inverted embossed or extruded cut feature where those teeth lock it in place.

 

Those won't hold that in place.

@soggyBottom you'll need to use rivet nuts or rivnuts. Alternatively, you can use a super short flat head socket cap screw and thread the 2 pieces you are joining.

 

They are called buttons and I haven't ever heard of anyone being able to buy them separately. Look at motorcycle brake rotors.

 

They are - get this - called rivets.

There are dozens if not hundreds of different styles of rivets. And each in many different sizes.

 

Why not take it to a bike shop and ask them?

 

They may have lots of names but they don’t function like a normal rivet. They allow for flex on a full floating disc brake rotor. They combine the two pieces of the rotor together. Look up the brand of rotor then search for them that way. This is a link for some on a motorcycle. Same brake system just smaller.

https://motowheels.com/i-7579497-co...31DdlNLkmMYDmWy4xwy0A63JoSZIMUpxoCDisQAvD_BwE