unit stress

例句：

1. 1. The material under this unit stress is very strong.
   这种材料在单位应力下非常坚固。
2. 2. The engineer calculated the unit stress of the beam.
   工程师计算了梁的单位应力。
3. 3. The stress in the material is due to the unit stress applied at the surface.
   材料中的应力是由于施加在表面的单位应力引起的。