Marco Haesche Dirk Lehmhus Jorg Weise Manfred Wichmann Irene Cristina
材料科学技术（英文）
Replacement of TiH2 as foaming agent by CaCO3 (lime) and CaMg(CO3)2 (dolomite) for AlMg4.5- and AlSi9Cu3-foams was investigated considering influences on foaming capability and cellular structure. Precursor materials were produced from alloy chip and powder mixtures by means of the thixocasting process. AlSi9Cu3 variants showed expansion levels sufficient for commercial use. Variations in expansion observed when CaCO3 and CaMg(CO3)2 were compared as foaming agent are explained based on the course of decomposition. Improved performance of dolomite-based foams relies on formation of stabilizing MgO phases, which do not develop during decomposition of CaCO3 in Al-Si-Cu alloys
关键词:
Aluminium foam
,
foaming agent
,
calcium carbonate
,
dolomite
,
stabilisation
张浩
,
郑德一
,
胡顺敏
,
彭贵贵
,
程程
,
张静
材料导报
doi:10.11896/j.issn.1005-023X.2017.06.003
通过铌铁矿先驱法制备了Pb(Mg1/3 Nb2/3) O3-Pb (Mn1/3 Nb2/3) O3-PbZrO3-PbTiO3+0.3％ CeO2(质量分数)+xSrCO3(PMN-PMnN-PZT-Ce-xSr,x=0.00,0.03,0.05,0.07)四元系压电陶瓷,研究了SrCO3含量的变化对Pb(Mg1/3Nb2/3)O3-Pb(Mn1/3-Nb2/3) O3-PbZrO3-PbTiO3 +0.3％CeO2(质量分数)(PMN-PMnN-PZT-Ce)压电陶瓷相结构、储能密度以及弛豫行为的影响.通过XRD表明,样品为单一稳定的钙钛矿结构,并且存在准同晶界(MPB);当x=0.07时,在外加电场60 kV/cm下取得较好的储能性能:储能密度W1 =0.31 J/cm3,储能效率η=0.47;通过修正Curie-Weise定律,较好地描述了陶瓷弥散相变的特征,弥散相变系数γ随着Sr2+掺杂量的增加而增加.当x=0.07时,γ取得最大值1.972 8,此时弛豫现象最明显.
关键词:
压电陶瓷
,
相结构
,
储能性能
,
介电弛豫
,
弥散相变
