Q: How do ceramic alumina screws compare to steel screws as far as strength goes? The load would most likely be tension, but some compression too.
A: If you compare 316 Stainless Steel to Zirconia ceramic screws, their tensile strengths are similar (around 75 ksi tensile) with Alumina ceramics being about 1/2 as strong. So you certainly can match the strength of 316 stainless steel with zirconia ceramics in constant compression or tension. However the ceramic screws will be much more brittle and susceptible to shock so care must be taken in the application.