When a finish is required to make two mating metals compatible, finish the metal which is found in the lower numbered grouping of Table 2. Metals given in Table 2 will, because of their inherent corrodibility, already be finished and the finish metal will be subject to the same rule.
当需要通过表面处理使两种相配合的金属变得相容时，应对表 2 中分类编号较小的金属做表面处理。表 2 中列出的金属因为其固有的腐蚀性，已经做有表面处理，且表面金属将受同一规则的约束。
For example, to couple metals separated by two or more groups (e.g., 4 to 2), find a finish which appears in Group 3 and 4. The Group 3 metal should be plated onto the Group 2 metal to make metals 2 and 4 compatible. The reason for this is, if the finish metal breaks down, or is porous, its area will be large in comparison to the exposed area of the Group 2 metal, and the galvanic corrosion will be less.
例如，要将相隔两类或更多类的金属耦合在一起（如 4 至 2），应在第 3 和第 4 类中查找一种表面处理做法。 应在 2 类金属上镀 3 类金属，以使得 2 类和 4 类金属相容。这样做的原因是，如果表面金属失效或穿孔，较 2 类金属的暴露面积而言，其面积会较大，电镀腐蚀会较低。
On aluminum, chromate conversion coatings (such as Iridite) can be considered as conductive finishes. MIL-DTL-5541F, Type I, Class 3 conversion coatings are required to have less than 200 milliohms resistance when measured at 200 psi contact pressure after 168 hours of exposure to a 5 percent salt spray.
在铝材上，铬酸盐转化涂层（如浸镀铬）可被视为导电表面。对于 MIL-DTL-5541F I 型 3 类转化涂层，在经过 5% 盐雾处理 168 小时后，当使用 200 psi 的接触压力进行测量时，其电阻应小于 200 毫欧。
Table 2: Metals Compatibility an important role in the electrical
表2:金属相容性
Metals Compatibility 金属相容性
Group
分类 Metal Groupings* 金属分类*
1 Gold – Platinum – Gold/Platinum Alloys – Rhodium – Graphite – Palladium – Silver – Silver Alloys – Titanium – Silver Filled Elastomers – Silver Filled Coatings
金 － 铂金 － 金/铂金合金 － 铑 － 石墨 － 钯金合金 － 银 － 银合金 － 钛 －掺银橡胶 － 含银涂层
2 Rhodium – Graphite – Palladium – Silver – Silver Alloys – Titanium – Nickel – Monel – Cobalt –Nickel and Cobalt Alloys – Nickel Copper Alloys – AISI 300 Series Steels – A286 Steel –Silver Filled Elastomers – Silver Filled Coatings
铑 － 石墨 － 钯金合金 － 银 － 银合金 － 钛 －镍 － 蒙耐合金 － 钴 － 镍钴合金 － 镍铜合金 － ANSI 300 系列钢 － A286 钢 － 掺银橡胶 － 含银涂层
3 Titanium – Nickel – Monel – Cobalt – Nickel and Cobalt Alloys – Nickel Copper Alloys – Copper –Bronze – Brass – Copper Alloys – Silver Solder – Commercial Yellow Brass and Bronze – Leaded Brass and Bronze – Naval Brass – Steels AISI 300 Series, 451, 440, AM 355 and PH hardened – Chromium Plate – Tungsten – Molybdenum – Certain Silver Filled Elastomers
钛 －镍 － 蒙耐合金 － 钴 － 镍钴合金 － 镍铜合金 － 铜 － 青铜 － 黄铜 － 铜合金 － 银焊料 － 工业黄铜和青铜 － 加铅黄铜和青铜 － 船用黄铜－ ANSI 300 系列、451、440、AM 355 和 PH 硬化钢 － 涂铬层 － 钨 － 钼 － 某些含银橡胶
4 Leaded Brass and Bronze – Naval Brass – Steels AISI 431, 440, 410, 416, 420, AM 355 and PH hardened – Chromium Plate – Tungsten – Molybdenum – Tin-Indium – Tin Lead Solder –Lead – Lead Tin Solder – Aluminum 2000 and 7000 Series – Alloy and Carbon Steel –Certain Silver Filled Elastomers – CHO-SHIELD 2000 Series Coatings
加铅黄铜和青铜 － 船用黄铜－ ANSI 431, 440, 410, 416, 420, AM 355 系列钢 和 PH 硬化钢 － 涂铬层 － 钨 － 钼 － 锡 － 铟 －锡铅焊料 － 铅 － 铅锡焊料 － 2000 和 7000 系列铝 － 合金钢和碳钢－ 某些含银橡胶 － CHO-SHIELD 2000 系列涂层
5 Chromium Plate – Tungsten – Molybdenum – Steel AISI 410, 416, 420, Alloy and Carbon –Tin – Indium – Tin Lead Solder – Lead – Lead Tin Solder – Aluminum – All Aluminum Alloys – Cadmium – Zinc – Galvanized Steel – Beryllium – Zinc Base Castings
涂铬层 － 钨 － 钼 － ANSI 410、416 、420 钢、合金钢和碳钢 － 锡 － 铟 －锡铅焊料 － 铅 － 铅锡焊料 －铝 － 所有铝合金 － 铬 － 锌 － 镀锌钢 － 铍 － 锌基铸造合金
6 Magnesium – Tin
钼 －锡
*Each of these groups overlap, making it possible to safely use materials from adjacent groups.
*各类相互重叠，以能够安全地使用相邻类中的材料。
Recommended MIL-DTL-5541F, Type I, Class 3 coatings are Alodine 600, or Alodine 1200 and 1200S dipped.
MIL-DTL-5541F I 型 3 类镀层建议为 Alodine 600 或 Alodine 1200 和 1200S 浸镀层。
Organic Finishes
有机表面
Organic finishes have been used with a great deal of success to prevent corrosion. Many organic finishes can be used, but none will be effective unless properly applied. The following procedure has been used with no traces of corrosion after 240 hours of MIL-STD-810B salt fog testing.
有机表面已大量成功地用于防腐蚀。有许多有机表面可以使用，但仅在正常使用时，才会有效。以下程序已通过 240 小时的 MIL-STD-810B 盐雾测试，未发现任何腐蚀迹象。
Aluminum panels are cleaned with a 20% solution of sodium hydroxide and then chromate conversion coated per MIL-DTL-5541F, Type I, Class 3 (immersion process). The conversion coated panels are then coated with MIL-C-46168 Type 2 urethane coating, except in the areas where contact is required. For maximum protection of aluminum flanges, a CHO-SHIELD 2000 series conductive coating and CHO-SEAL 1298 conductive elastomer gasket material are recommended. For additional information, refer to Design Guides for Corrosion Control, page 55.
使用 20% 的氢氧化钠溶液清洗铝板，然后按 MIL-DTL-5541F I 型 Class 3 类做法涂装铬酸盐转化层（浸镀工艺）。然后，对做有转化层的铝板涂一层 MIL-C-46168 2 型聚氨酯，需要接触的区域除外。为提高对铝凸缘的保护程度，建议采用 CHO-SHIELD 2000 系列导电涂层和 CHO-SEAL 1298 导电橡胶垫片材料。有关更多信息，请参见第 55 页腐蚀控制设计指南。
The finish coat can be any suitable urethane coating that is compatible with the MIL-C-46168 coating. It is important to note that test specimens without the MIL-C-46168 coating will show some signs of corrosion, while coated test specimens will show no traces of corrosion.
表面涂层可为与 MIL-C-46168 涂层相容的任意合适的聚氨脂涂层。需要重点说明的是，未经 MIL-C-46168 涂层处理的样件会出现一些腐蚀迹象，而经过该涂层处理的试件不会显示任何腐蚀迹象。
ChO-Shield? 2000 Series Coatings
ChO-Shield? 2000 系列涂层
When using CHO-SHIELD 2000 series conductive urethane coatings it is important to prepare the surface to attain maximum adhesion. The easily mixed three-component system allows minimum waste with no weighing of components, thus eliminating weighing errors. Because of the filler loading of the 2000 series coatings, it is recommended that an air agitator cup be incorporated into the spray system to keep the conductive particles in suspension during the spraying sequence. It is recommended that approximately 7 mils of wet coating be applied. This thickness can be achieved by spraying multiple passes, with a ten minute wait between passes.
当使用 CHO-SHIELD 2000 系列聚氨酯导电涂层时，对涂装表面进行制备，以达到最高附着性非常重要。这种易于混合的三组分系统因为不需要对组分计重，因此可以避免计重错误，浪费量很低。因为 2000 系列涂层带有填料，建议在喷涂系统中加入一个气动搅拌杯，以使导电颗粒在喷涂过程中保持悬浮状态。建议涂层湿膜厚度约 7。可通过多遍喷涂达到此厚度，每遍之间间隔十分钟。 |
