With the increasing demand of high quality carburizing steel for key spare parts as well as proposal of “carbon peaking and carbon neutrality goals”, the requirements for such comprehensive properties of carburizing gear steel as wear resistance and strength and toughness are higher. It is the development direction of carburizing gear steel to develop high efficiency, energy saving, low carbon and economic high temperature carburizing technology with rare earth microalloying. In the paper, it is discussed the key problems and regulation of microstructure and properties for applications of rare earth in high temperature carburizing gear steel as well as summarized the applications and development trend of high temperature carburizing for gear steel with rare earth microalloying through introducing the applications and development situations of high temperature carburizing gear steel at home and abroad, which are of great significances for developing high temperature carburizing gear steel with rare earth characteristics.
| 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 |