Carpenter Glass Sealing 27 is a ductile chromium-iron alloy that has been used for strong glass-to-metal seals in electronic and vacuum tubes, and incandescent and fluorescent lamps. It exhibits no phase transformation up to 1150 deg C (2100 deg F). This datasheet provides information on composition, physical properties, and elasticity. It also includes information on corrosion resistance. Filing Code: FE-136. Producer or source: Carpenter Technology Corporation.