Abstract
A carburization model consisting of carbon diffusion and carbide precipitation for high Cr-Ni alloy at elevated temperature was established based on Fick's second law and equilibrium constant method. The concentration field of carbon in Cr25Ni35Nb and Cr35Ni45Nb alloys for ethylene cracking furnace tube during carburization was simulated by means of finite difference method. The distribution of total carbon content, carbon and metallic elements in matrix along thickness of the tube at different time in the process of carburizing was investigated. The pack solid carburization tests of the two alloys were carried out at 1000°C. In the meantime, carburization kinetic curves and carburizing resistance of the two alloys were studied. It shows that the calculated results are in agreement with the experimental results. The comparison of the weight gain profiles and carbon distribution profiles between the two alloys obviously shows that the anti-carburization property of Cr35Ni45Nb alloy is better than that of Cr25Ni35Nb alloy.
| Original language | English |
|---|---|
| Pages (from-to) | 151-156 |
| Number of pages | 6 |
| Journal | Cailiao Rechuli Xuebao/Transactions of Materials and Heat Treatment |
| Volume | 31 |
| Issue number | 7 |
| State | Published - Jul 2010 |
Keywords
- Carburization
- Equilibrium constant method
- Fick's second law
- Numerical simulation