六角钢 hexagonal steel 是型钢的一种，也称之为六角棒，截面为正六边形的棒材。以对边长度S为标称尺寸。<机械设计手册-常用工程材料>及国标《GB 705-89 热轧六角钢和八角刚尺寸、外形、重量及允许偏差》有更多介绍。
六角钢
规格
常用规格尺寸
| 对边距离S mm | 允许偏差， mm | 截面面积A, cm2 | 理论重量， kg/m |
| 1组 | 2组 | 3组 | 六角钢 | 八角钢 | 六角钢 | 八角钢 |
| 8 | ±0.25 | ±0.35 | ±0.40 | 0.544 3 | - | 0.435 | - |
| 9 | 0.701 5 | - | 0.551 | - |
| 10 | 0.866 | - | 0.680 | - |
| 11 | 1.048 | - | 0.823 | - |
| 12 | 1.247 | - | 0.979 | - |
| 13 | 1.464 | - | 1.15 | - |
| 14 | 1.697 | - | 1.33 | - |
| 15 | 1.949 | - | 1.53 | - |
| 16 | 2.217 | 2.120 | 1.74 | 1.66 |
| 17 | 2.503 | - | 1.96 | - |
| 18 | 2.808 | 2.683 | 2.20 | 2.16 |
| 19 | 3.126 | - | 2.45 | - |
| 20 | 3.464 | 3.312 | 2.72 | 2.60 |
| 21 | ±0.30 | ±0.40 | ±0.50 | 3.819 | - | 3.00 | |
| 22 | 4.192 | 4.088 | 3.29 | 3.15 |
| 23 | 4.581 | - | 3.60 | - |
| 24 | 4.988 | - | 3.92 | - |
| 25 | 5.413 | 5.175 | 4.25 | 4.06 |
| 26 | 5.854 | - | 4.60 | - |
| 27 | 6.314 | - | 4.96 | - |
| 28 | 6.790 | 6.492 | 5.33 | 5.10 |
| 30 | 7.794 | 7.452 | 6.12 | 5.85 |
| 32 | ±0.40 | ±0.50 | ±0.60 | 8.868 | 8.479 | 6.96 | 6.66 |
| 34 | 10.011 | 9.572 | 7.86 | 7.51 |
| 36 | 11.223 | 10.731 | 8.81 | 8.42 |
| 38 | 12.505 | 11.956 | 9.82 | 9.39 |
| 40 | 13.86 | 13.25 | 10.88 | 10.40 |
| 42 | 15.28 | - | 11.99 | - |
| 45 | 17.54 | - | 13.77 | - |
| 48 | 19.95 | - | 15.66 | - |
| 50 | 21.65 | - | 17.00 | - |
| 53 | ±0.60 | ±0.70 | ±0.80 | 24.33 | - | 19.10 | - |
| 56 | 27.16 | - | 21.32 | - |
| 58 | 29.13 | - | 22.87 | - |
| 60 | 31.18 | - | 24.50 | - |
| 63 | 34.37 | - | 26.98 | - |
| 65 | 36.59 | - | 28.72 | - |
| 68 | 40.04 | - | 31.43 | - |
| 70 | 42.53 | - | 33.30 | - |