I had had pretty bad experiences with Rocket Ring chainrings. They just wouldn't last. Well, today I paid attention at what is written on the label, and I read that they're made of 6061-T6 aluminum alloy. Then I looked up the catalogues, and found out that 6061-T6 has 95 Brinell hardness, which is a JOKE! Of course they don't last, when they are made of such soft material!

For comparison, Salsa chainrings are made of 7075 aluminum alloy, which has 150 Brinell hardness.


(For more comparison, a typical austenitic stainless steel has 160 to 210 on the Brinell scale - and nitrogen strenghtened will go over 230. High carbon (non stainless) steels have Brinell hardness above 260 - typically around 300, but over 330 exist.)