The microstructure evolution of Al–Sr master alloy during continuous extrusion was investigated using X-ray diffractometer, scanning electron microscope and transmission electron microscope. Results indicate that the continuous extrusion process could change the Al4Sr particles of the alloy significantly in size and morphology. The as-cast needle-like Al4Sr particles are broken into small blocks in upsetting zone and crushed heavily in adhesion zone. Plenty of dislocations get tangled up in right-angle bending zone. Al4Sr particles grow in the extending zone. Finally, Al4Sr particles in products are approximately 28μm in length. Al2Sr particles precipitate during the process. Compared with products by horizontal extrusion, Al4Sr particles by continuous extrusion are finer and distribute more evenly.%利用X射线衍射仪(XRD)、扫描电镜(SEM)和透射电镜(TEM)对铝锶中间合金连续挤压过程中组织演变进行研究.结果表明:连续挤压工艺可以显著改变铝锶中间合金中Al 4 Sr相的大小和形态.铸态针状的Al 4 Sr粒子在镦粗区破碎成小块状,并在粘着区严重破碎;在直角弯曲区大量位错缠结在一起;在扩展区Al 4 Sr粒子开始长大;最终,产品中Al4Sr粒子的长度约为28μm.在连续挤压过程中有Al2Sr粒子析出.与卧式挤压产品相比,连续挤压产品中Al 4 Sr粒子更加细小均匀.
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