In a former job I was working in a facility that used CNC machines to etch quartz with an HF solution. The parts were in a special PVC tray that was fixtures on a stainless steel base. The stainless steel base wouldn’t align properly so I pulled it out and it looked like it had been made from a sintered stainless. Over many years the acid had dissolved part of the SS and made it porous (but it was still very flat). I replaced the SS with PVC and it held up for the remainder of my involvement with the machines.