以玻璃纤维复合材料板为研究对象，通过断铅试验分析了声发射信号在复合材料中的衰减规律和传播速度规律。根据试验结果对波速表达式进行了多项式拟合，得到了声发射信号沿任意方向传播时的传播速度，利用多项式计算得到的波速进行线性定位，其定位误差在3%以内，验证了波速-传播方向多项式的有效性，为后期玻璃纤维复合材料声发射源定位研究奠定了基础。

Attenuation and speed law of acoustic emission signal in composite materials were analyzed through breaking the pencil lead to simulate acoustic emission signals in glass fiber composite material plate. The polynomial of propagation speed was got based on the measured result by fitting. The signal propagation velocity of any angle can be got through the polynomial of wave-direction of propagation. And the polynomial was verified by lead positioning test that the position error with the speed calculated by the polynomial was less than three percent,which laid a foundation for the research of acoustic emission source localization period of glass fiber reinforced plastic.