LY12：
Cu3.8-4.9%、Mn0.3-0.9%、Mg1.2-1.8%、Zn0.25%、Cr0.1%、Ti0.15%.
LY13：
Cu2.2-3%、Mn0.2%、Mg0.2-0.5%、Zn0.25%、Cr0.1%.
LY17：
Cu6.0-7.0%、Mn0.4-0.8%、Mg0.25-0.45%、Be0.1-0.2%.