The grain growth kinetics of the conversion from fersmite to pyrochlore during high-temperature sintering process was investigated. The results show that the conversion rate of fersmite increases with rising sintering temperature, and the pyrochlore content reaches 96.07% at 760 ℃. At the temperature within the range of 760-880 ℃, the average grain size of pyrochlore increases with the extension of holding time at the same sintering temperature and also increases with the rising of sintering temperature at the same holding time. The grain growth exponents within this temperature range are all greater than 3, presenting a three-dimensional grain growth characteristic. The apparent activation energy of grain growth decreases with rising temperature, making it easier for grain to grow. At the same sintering temperature, the apparent activation energy of grains increases with the extension of holding time, indicating that it is more difficult for grains to grow after the holding time is prolonged. It is concluded that grain growth can be reliably promoted by appropriately increasing the sintering temperature or adding modifiers rather than by merely extending holding time.
| 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 |