| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 833859 | Materials & Design (1980-2015) | 2006 | 5 Pages |
In this study, heat resistant carrying baskets’ microstructural and mechanical properties were investigated in order to increase the service life of them. By making some adjustments in alloying elements of these steels promising results were obtained. Heat resistant baskets used in heat treatment furnaces have approximately six or seven months service lifes and produced according to DIN 14849 X 40 NiCrSiNb 3818 norm by casting. By changing service, life of baskets manufactured according to DIN 14958 X 5 NiCrAlTi 3120 has been increased to over 18 months.The samples are exposed to the following operations in every heat treatment cycle: The heat treated parts are firstly, held in hardening furnace at 870 °C for 270 min. They are immersed in oil at 50 °C for 8 min. After infiltration for 8 min, they are waited in open air for 135 min. Then these parts are tempered in a furnace at 570 °C for 270 min. Finally, they are immersed into oil bath at 60–80 °C for 7 min. The total time consumed in this process is 750 min. As a result of this repeated heat treatment cycles, it was seen that the graphites in microstructure have been taken a spherical shape. Therefore, the strength of baskets was improved and service lifes of them were increased from 6 to 18 months.
