polycrystalline aggregate

例句：

1. 1. The engineer analyzed the structure of the polycrystalline aggregate to determine its strength and weaknesses.
   工程师分析了多晶体集合体的结构，以确定其强度和弱点。
2. 2.In the construction industry, polycrystalline aggregate is commonly used as a building material.
   在建筑业中，多晶体集合体通常被用作建筑材料。
3. 3. The research team found that the polycrystalline aggregate had a significant impact on the performance of the concrete.
   研究团队发现，多晶体集合体对混凝土的性能有显著影响。