molding gravel是什么意思

用法例句

Effects of Mn and Al-Ti-B on the microstructure and properties of ZA27 alloy prepared by sand-casting technology were studied with the help of SEM and electronic universal testing machine.

利用扫描电镜和电子万能试验机研究了复合添加锰及铝-钛-硼中间合金对砂模铸造ZA27合金组织和性能的影响。