Edge crack defects occur frequently during the hot rolling process of low-temperature oriented silicon steel, and remain one of the primary quality problems in hot-rolled coils of oriented silicon steel. Through methods such as microstructure observation, energy spectrum analysis, and thermal simulation experiments, the cause of edge crack formation was identified as decarbonization and coarsening of ferritic grain boundaries during prolonged high-temperature heating of the slab. During rolling, grain refinement through the γ→α phase transformation was impeded, and recrystallization was suppressed by low edge temperatures. The resulting coarse and elongated non-recrystallized microstructure exhibited high brittleness, and tearing during rolling led to the formation of microcracks, which further propagated into edge cracks in the finishing stage. By adopting optimized heating and rolling strategies such as seamless charging, lower heating temperature, shorter heating time, high reduction rough rolling, fewer-pass rapid rolling, heavy vertical edge rolling, and edge heater temperature compensation, the edge quality qualification rate of hot-rolled oriented silicon steel coils increased from 76.3% to 85.2%,
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |