[somat]

A thought I had when I saw the original Steve Mould video, and this video made me remember it.

What happens if you just use glass for the bouncing surface? I was reading about the materials and I am not sure what property contributes to it's bounciness, but I think it is tensile strength(but it may be surface hardness). and regular glass has a slightly lower tensile strength than these amorphous metallic structures, fused quartz has a higher tensile strength, and I was unable to find out what tempered glass is, but I suspect tempered glass would tend to shatter if a small hard ball was bounced off it. Anyway, I was unable to form a good hypothesis as to what would happen, but I did find that mcmaster-carr sells fused quartz disks if anyone wants to try.

https://www.mcmaster.com/products/glass-discs/ultra-high-tem...

[JKCalhoun]

Steve Mould's video: https://youtu.be/QpuCtzdvix4

Grand Illusions original video: https://youtu.be/EzFjZJEAt18

[nabilhat]

McMaster also sells discs of tool steel and glass bearing balls... and carbide, and ceramic, etc. What if the bearing ball was carbide, even harder? What would happen if you reduced the hardness of a steel ball, which usually only requires normal kitchen oven temperatures? What happens if the materials switch places, say a hardened tool steel disc and glass ball?

Anyway, lots of options to safely experiment with material science concepts in very accessible and tweakable ways! No beryllium or foundry equipment required. I do think the massive, well fitted, rigid surface backing up the disc is important to constrain what this is demonstrating - plastic vs elastic deformation.

[DoctorOetker]

What counts is not specifically hardness or elasticity, but the hysteresis loop up to the stress and strain involved for a ball of a certain mass falling from a certain height.