well, I'm no engineer and no training in metallurgy, so ya'll can have at it, but I do understand metal/mineral/substance hardness ratings.
And common sense. (lol, my opinion
)
So a stainless steel prop at the moment of impact will transfer a lot more of that kinetic energy downstream to whatever it is connected to. So whatever force is necessary to bend/break other components has a higher chance of existing.
That plastic/rubber sacrificial hub will still initially transfer that impact energy before spinning.
The initial full impact on that aluminum prop will be dissipated by the tearing/bending of that aluminum.
right?..or wrong.
And common sense. (lol, my opinion

So a stainless steel prop at the moment of impact will transfer a lot more of that kinetic energy downstream to whatever it is connected to. So whatever force is necessary to bend/break other components has a higher chance of existing.
That plastic/rubber sacrificial hub will still initially transfer that impact energy before spinning.
The initial full impact on that aluminum prop will be dissipated by the tearing/bending of that aluminum.
right?..or wrong.