Steel material that is magnetic and stable when machined
Hello-
I am designing a series of inspection plates for a family of aluminum parts. I want the plate to be steel so that it won't wear when switching out batches of parts. I don't really need a super hard steel, just as long as its togher thatn aluminum. I would like the steel to be stable when machined and magnetic, so that a grinder can be used to achieve the .0004in./3.0X3.0in. flatness tolerance that I need. Right off the top of my head, 416 SS is the only steel that would work, but its pretty pricey.
What other steel is magnetic and will stay stable when machined?
Thanks!