Havar, or UNS R30005, is an alloy of cobalt, possessing very high mechanical strength. It can be heat-treated. It is highly resistant to corrosion and is non-magnetic. It is biocompatible. It has high fatigue resistance. It is a precipitation hardening superalloy. Havar foils of various thickness are used as diaphragms for pressure sensing in process control equipment, biocompatible medical implants, as particle beam windows in nuclear physics, and various other high temperature applications.