多孔Mg97Zn1Y2材料的力学性能与阻尼性能

Mechanical and Damping Properties of Porous Mg97Zn1Y2 Composites

多孔材料是一种新型轻质的结构-功能材料,具有较高的阻尼性能,同时兼具密度小、质量轻等特点,使其具有广阔的应用价值。基于此,选取含有长周期特殊结构相(LPSO相)的Mg97Zn1Y2为基体,以MgCO_(3)为发泡剂,SiC为增粘剂,通过熔体发泡法制备出镁基多孔材料,通过OM、SEM、TEM、XRD及DMA等技术手段,研究多孔Mg97Zn1Y2材料的力学性能、阻尼性能等。结果表明,多孔Mg97Zn1Y2材料主要由镁基体(α-Mg)、LPSO相和SiC相组成,当应变幅值较小时,多孔Mg97Zn1Y2复合材料的阻尼值明显优于Mg97Zn1Y2合金,随着孔隙率的增加,阻尼性能得到改善。孔隙率的增加降低了多孔Mg97Zn1Y2复合材料的抗压缩性能。此外,除了Mg97Zn1Y2合金本身的位错阻尼、界面阻尼和晶界阻尼之外,还有“气相”阻尼,共同影响着多孔Mg97Zn1Y2材料的阻尼性能。

Porous material is a new type of lightweight structure-functional material with high damping performance,low density,light weight,and other characteristics,making it useful in many applications.Mg97Zn1Y2 with long-period stacking ordered phase(LPSO phase)as a matrix,MgCO_(3) as foaming agent and SiC as tackifier was used to prepare magnesium-based porous materials by melt-foaming method.The mechanical properties and damping properties of the porous Mg97Zn1Y2 were studied by OM,SEM,XRD and DMA technology.Results show that the porous Mg97Zn1Y2 composites are mainly composed of magnesium matrix(α-Mg),LPSO phase and SiC phase.When the strain amplitude is small,the damping value of porous Mg97Zn1Y2 composites is obviously better than that of Mg97Zn1Y2 alloy,and the damping properties are improved as porosity is increased.However,increased porosity decreases the compression properties of porous Mg97Zn1Y2 composites.In addition to the dislocation damping,interface damping,and grain boundary damping of the Mg97Zn1Y2 alloy,“gas phase”damping is found to affect the damping properties of the porous Mg97Zn1Y2 composites jointly.