absoluteBLACK Super Steel eMTB chainrings go harder...at a price
Compared to cheaper stamped steel chainrings that come stock on many bikes, the new absoluteBLACK Super Steel e-bike chainrings start as a harder premium steel block, then get milled down to separate spiders and chainrings.
From there, they’re heat treated to increase strength, then given multiple "nitriding and carburizing" surface treatments to achieve a 1300HV hardness rating. They say that's 4x harder than typical stamped steel chainrings.
Side note: absoluteBLACK isn't the only one offering CNC’d e-bike chainring upgrades. Hope, Rotor, and others offer them, but they’re made from aluminum, not steel.
There's nothing wrong with aluminum, that's what aB's standard chainrings are made from, but they say the added torque from an e-bike motor can wear stamped (and, presumably, alloy) chainrings more quickly. Which then wears the chain, and then the cassette, more quickly, too.
So, despite these chainrings costing €189.95 and the spider ranging from €120 to €140, they say it can give you up to 3x the lifespan on the rest of your drivetrain. And, cassettes and chains are expensive these days, too. Spider and chainring are sold separately, so you can replace just the chainring if/when you do wear it out.
Why so expensive? They say the block of raw material costs them more than the retail price of a typical chainring, and because it's so much harder, it takes significantly more time to CNC.
The Super Steel e-bike chainrings come in two versions, one optimized for 12spd Shimano HG+ chains, and one for regular 11/12spd regular chains.
Spiders are available for these e-bike motors:
Spiders come in 4 colors: black, red, gold, and titanium, and they come with titanium chainring bolts.
The chainrings are only compatible with these spiders, and only come in a "titanium" color with your choice of 32/34/36/38 tooth counts. Just keep in mind, some e-bike systems are optimized for the stock tooth count chainrings, so double check with the manufacturer before changing chainring size.