From The Brick Experiment Channel comes this test: "Let's see how Lego-compatible stainless steel axle deforms or breaks when high torque is applied. The test bench is made using only plastic Lego parts. Enjoy!"

Spoiler: the steel piece barely holds form at 5 Newton metres of torque, gives slowly at 9, and twists like warm candy at 15. Read the rest

https://boingboing.net/2020/03/15/lego-makes-short-work-of-steel.html