What magnetic encoder rings are used in high temperature conditions?

Currently, the high-temperature resistant magnetic rings that manufacturers can produce are made of ferrite and neodymium iron boron. The high temperature resistance is 180 degrees. The advantage of ferrite is that it is cheap, but because it is fragile, it must be used with an aluminum alloy base. , the advantage of NdFeB is that it does not require an aluminum alloy base and is suitable for precision equipment, but the price is relatively high. I hope the above can help you!