Description
Alloy 27, it’s glass-to-metal sealing and iron-chromium alloy. Nominally 28 % chromium, in strip, bar, wire, and rod forms intended primarily for sealing to glass in electronic applications. UNS K92801 should only be considered for use at service temperatures below 300°C. The alloy is prone to sigma phase formation at temperatures close to 620°C, and exhibits brittle mechanical behavior after prolonged exposures at temperatures close to 475°C.
Application
It is applied to seal the equipment of the electric component with the soft glass.
Parameter
Typical chemistry:
| C | P | S | Mn | Si | Ni | N | Cr | Fe |
| ≤ | ||||||||
| 0.12 | 0.02 | 0.02 | 1.00 | 0.70 | 0.50 | 0.20 | 27.0-29.0 | Balance |
Notes: Under condition that the average coefficient of the linear expansion meets the requirements of the standard, the content of chromium is allowed to deviate from the stated range.
| Heat Treatment of the Samples | Average Coefficient of Linear Expansion |
| 20～530°C | |
| Heat to 1100±20°C, hold for 15min., cool to room tempreture in the air. | 10.8～11.4 |
Notes: The hardness of the annealed strip should be no more than 170. Hardness inspection is not required when the thickness of the strip is less than 0.2mm.
Average Coefficient of Linear Expansion:
| 20-200℃ | 20-300℃ | 20-400℃ | 20-500℃ | 20-600℃ | 20-700℃ | 20-800℃ |
| 10.00 | 10.50 | 10.80 | 11.10 | 11.20 | 11.60 | 11.60 |
Size Range
| Sheet | Thickness:0.10mm~3.50mm, width: ≤300mm |
| Plate | Thickness:3.5mm~40.0mm, width: ≤500mm |
| Round wire | Thickness:0.10mm~5.0mm |
| Flat Wire | Dia 0.5mm~Dia 5.0mm, length≤1000 |
| Rod | Dia 5.0mm~Dia 8.0mm, length≤2000 |
| Dia 8.0mm~Dia 32.0mm, length≤2500 | |
| Dia 32.0mm~Dia180.0mm, length≤1000 | |
| Capillary | OD 8.0mm~1.0mm,ID 0.1~8.0 length≤2500 |
| Pipe | OD 120mm~8.0mm,ID 8.0~129 length≤4000 |
Condition: (With max tolerance) cold rolled, cold drawn, hot rolled , hot forging ,peeled turned ,bright ,bright annealed
