1.1 This specification covers two chromium-iron alloys, the former, (UNS K91800), nominally 18 % chromium, balance iron, the latter, (UNS K92801), nominally 28 % chromium, in strip, bar, wire, and rod forms intended primarily for sealing to This specification covers two chromium-iron alloys, one is UNS K91800 with nominally 18% chromium, balance iron, and the other is UNS K92801 with nominally 28% chromium, both in strip, bar, wire, and rod forms intended primarily for sealing to glass in