A laminated composite bar of rectangular crosssection consists of a middle portion of one material as well as upper and lower identical cover plates of another material.
一矩形横截面的叠层复合材料杆，由以一种材料为中心部分，及另一种材料的上下两相同的盖板所组成。
2
Using a 1/16" drill bit, drill a hole in the middle of the crosssection tube above. This will allow gas to escape during welding."
使用1 / 16“钻头，钻一个孔在上面管中间的横截面。这将使天然气逃脱焊接过程。
3
The apparent difference in elemental distribution in the bone crosssection showed that the enrichment or loss of elements can occur not only in the inner and outer surface, but also in the middle.