# metal

* [AWG](#awg)
  * [多股硅胶线](#多股硅胶线)
* [密度](#密度)
* [电阻率](#电阻率)
* [镀层](#镀层)

## AWG

| byGemini | Diameter (inches) | Diameter (mm) | Area | Resistance (Ohms/km) | Typical Max Ampacity\* |
| -------- | ----------------- | ------------- | ---- | -------------------- | ---------------------- |
| **1**    | 0.289             | 7.35          | 42.4 | 0.407                | 110A - 130A            |
| **2**    | 0.258             | 6.54          | 33.6 | 0.513                | 95A - 115A             |
| **4**    | 0.204             | 5.19          | 21.2 | 0.815                | 70A - 85A              |
| **6**    | 0.162             | 4.11          | 13.3 | 1.30                 | 55A - 65A              |
| **8**    | 0.128             | 3.26          | 8.37 | 2.06                 | 40A - 50A              |
| **10**   | 0.102             | 2.59          | 5.26 | 3.28                 | 30A                    |
| **12**   | 0.081             | 2.05          | 3.31 | 5.21                 | 20A                    |
| **14**   | 0.064             | 1.63          | 2.08 | 8.29                 | 15A                    |
| **16**   | 0.051             | 1.29          | 1.31 | 13.2                 | 10A - 13A              |
| **18**   | 0.040             | 1.02          | 0.82 | 21.0                 | 7A - 10A               |
| **20**   | 0.032             | 0.81          | 0.52 | 33.3                 | 5A                     |
| **22**   | 0.025             | 0.64          | 0.33 | 53.0                 | 3A - 5A                |
| **24**   | 0.020             | 0.51          | 0.21 | 84.2                 | 2A - 3.5A              |
| **26**   | 0.016             | 0.40          | 0.13 | 134.0                | 1A - 2.2A              |
| **28**   | 0.013             | 0.32          | 0.08 | 213.0                | 0.5A - 1.4A            |
| **30**   | 0.010             | 0.25          | 0.05 | 339.0                | 0.5A - 0.8A            |

* "3-Gauge" Rule: doubles the cross-sectional area
* "6-Gauge" Rule: doubles the wire diameter

### 多股硅胶线

| byGrok | mm²        | 股数×单股直径 (约)         | 外径 (mm) 约 | 最大A | 40℃额定A  |
| ------ | ---------- | ------------------- | --------- | --- | ------- |
| 26     | 0.14       | 7×0.16 或 30×0.08    | 1.8–2.2   | 3.5 | 2.5–3.0 |
| 24     | 0.22       | 7×0.20 或 40×0.08    | 2.0–2.5   | 5.5 | 4.0–4.5 |
| 22     | 0.35       | 7×0.25 或 65×0.08    | 2.3–2.8   | 8.0 | 6.0–7.0 |
| 20     | 0.5        | 7×0.30 或 100×0.08   | 2.6–3.2   | 11  | 8–9     |
| 18     | 0.75       | 19×0.23 或 150×0.08  | 3.0–3.8   | 16  | 12–14   |
| 16     | 1.0 / 1.3  | 19×0.30 或 196×0.08  | 3.4–4.2   | 22  | 17–20   |
| 14     | 2.0 / 2.08 | 41×0.25 或 324×0.08  | 4.2–5.0   | 32  | 25–28   |
| 12     | 3.3 / 3.31 | 65×0.25 或 513×0.08  | 5.0–6.0   | 41  | 33–38   |
| 10     | 5.26       | 105×0.25 或 826×0.08 | 6.0–7.2   | 55  | 45–50   |
| 8      | 8.37       | 168×0.25            | 7.5–8.5   | 80  | 65–70   |
| 6      | 13.3       | 266×0.25            | 9.0–10.5  | 105 | 85–95   |

## 密度

<https://en.wikipedia.org/wiki/Densities\\_of\\_the\\_elements\\_(data\\_page)#Density,\\_solid\\_phase>

```
13 Al aluminium 2.70 g/cm3
26 Fe iron      6.98 g/cm3
29 Cu copper    8.02 g/cm3
47 Ag silver    9.32 g/cm3
82 Pb lead     11.34 g/cm3
79 Au gold     19.3  g/cm3
```

## 电阻率

<https://zh.wikipedia.org/wiki/%E7%94%B5%E9%98%BB%E7%8E%87>

| 物质  | 电阻率 (Ωm)  |
| --- | --------- |
| 石墨烯 | 1.00×10−8 |
| 银   | 1.59×10−8 |
| 铜   | 1.7×10−8  |
| 金   | 2.44×10−8 |
| 铝   | 2.82×10−8 |
| 黄铜  | 8×10−8    |
| 铁   | 10×10−8   |

<http://www.elektrisola.com/cn/conductor-materials/comparison-of-metals.html\\>
![](https://pic3.zhimg.com/v2-c62dd9e9abb89511164888df8e558b3a_r.jpg)

## 镀层

<https://www.zhihu.com/question/57329327>

```
接线应采用相同的表面处理，铜镀锡与铜镀银接触，锡面会被氧化腐蚀。
活泼: 锡>铜>银
镀镍：不生铜锈
银：价贵；易氧化，在电场的作用下容易迁移
要求严格的地方，触点用铂或者铼合金
```