With the development of automobile lightweight technology, the substrates of truck body have changed from cold-rolled steel sheet to aluminum alloy mixed with cold-rolled steel, which has brought about the demand for co-line coating of steel and aluminum alloy. Therefore, this paper, based on the tests of the degreasing, surface conditioning, phosphating and electrophores, discussed the pretreatment process scheme of steel-aluminum co-line phosphating. The research results show that the degreasing corrosion of aluminum alloy should be controlled below 100 mg/m2 when the co-line coating of steel and aluminum is carried out, and the surface conditioner XG, by contrast, has a more significant effect on the phosphating of aluminum alloy. When the concentration of fluoride ions in phosphating solution is 150~240 mg/L, the corrosion resistance of electrophoresis films on DC04 cold-rolled steel plate, 5052 and 6061 aluminum alloy substrate can meet 1 000 h of neutral salt spray test requirements. The research results provide technical support for the application of steel-aluminum co-line coating technology.
| 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 |