焊接结构钢(While carbon remains the cheapest way of obtaining strength, many modem steels for welded structures need to have carbon contents below 0. 20 per cent if adequate weldability is to be ensured. 虽然添加碳元素仍然是钢获得高强度最廉价的途径，但是许多现代焊接结构钢如果要保证具有良好的焊接性，其含碳量必须低于0. 20%。)
