The hot-rolled coil with X52MS pipeline steel for acid service by industrial production is chosen as the research object as well as its material performances are analyzed from microstructure and chemical components. Its resistance to hydrogen induced cracking (HIC) behavior in H2S solution is mainly studied, the effects of microstructure and microregion components on the resistance to HIC are investigated by HIC test as well as the main causes for crack generation are analyzed so that its regularities are found out. It is summarized that banded structure is the main cause for failure of resistance to HIC for this material, carbon segregation and central aggregation of inclusion of carbohydrates and nitrogenous compounds would worsen the effects of banded structure on the HIC performance; the thought of low carbon component design is the premise of designing pipeline steel for acid service as well as reasonable control of nitrogen content is also one of the considerations in production of pipeline steel for acid service.
| 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 |