Experimental study of the Be–Si phase diagram
Experimental study of the Be–Si phase diagram
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DOI：
10.1007/s10853-006-5244-5
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发表时间：
2006-02
影响因子：
4.5
通讯作者：
Zhu Pan;Yong Du;Bai-yun Huang;Hong-hui Xu;Yong Liu;Hai-lin Chen;W. Xiong;R. Schmid-Fetzer
中科院分区：
文献类型：
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作者：
Zhu Pan;Yong Du;Bai-yun Huang;Hong-hui Xu;Yong Liu;Hai-lin Chen;W. Xiong;R. Schmid-Fetzer
Wang等人[1]报道，在铸态Al-11Si-0.3镁合金中加入少量的Be，与不添加Be的合金相比，亚稳β的析出速度更快，热效应更强，显著提高了铸态时效时的峰值硬度。Yin等人[2]和Yie等人[3]都发现，在Al-4.93Si-1.4Fe-0.63 mg-1.45Cu[2]和Al-11.1Si-1.03Fe-0.08Ti等工业铝合金中添加Be有利于针状富铁相向汉字的转变。一般认为，针状富铁相对材料的强度和塑性有害。本文研究了Be对Al-Cu-Fe和Al-Mn系合金等铝基合金准晶形成能力的影响[4]。研究发现，Be的加入改变了二十面体相(I相)的形成机制，使其由包晶反应转变为初凝状态，并使I相的体积分数增加[4]。此外，Be替代Al显著降低了形成I相所需的临界Mn含量和冷却速度[4]。Chen等人[5]证明了Al在Al80Mn20(at.%)二元合金中的部分取代Al完全抑制了五方准晶T相的形成，并显著改变了I相的组织。因此，对Be-Si系相图和热力学性质的了解对指导铝基准晶材料和多元商用铝合金的设计和加工具有重要意义。该二元相图是一种简单的共晶相图。Masing和Dahl[6]对Be-Si相图的建立做出了主要贡献。利用热分析技术，他们[6]测量了四种双金属氧化物的相变温度。
Wang et al.[1] reported that minor addition of Be in the as-cast Al-11Si-0.3 Mg alloy (wt.%) causes faster precipitation and more heat effect of metastable β than the alloy without addition of Be and considerably increases the peak hardness achieved during as-cast aging. Both Yin et al.[2] and Yie et al.[3] have found that the addition of Be into commercial Al alloys, such as Al-4.93 Si-1.4 Fe-0.63 Mg-1.45 Cu [2] and Al-11.1 Si-1.03 Fe-0.08 Ti alloys [3], is beneficial for the transformation of the needleshaped iron-rich phase into the Chinese scripts. It is generally believed that the needle-shaped iron-rich phase is harmful to the strength and ductility of materials. The influence of Be addition on the quasicrystal-forming ability in Al-based alloys, such as alloys in the Al–Cu–Fe and Al–Mn systems, has been investigated [4]. It was found that Be addition modified the icosahedral phase (i-phase) formation mechanism from peritectic reaction to primary solidification and resulted in the increase of the volume fraction for the i-phase [4]. In addition, the substitution of Al by Be was found to reduce significantly the critical Mn content and cooling rate necessary for the formation of i-phase [4]. Chen et al.[5] demonstrated that the partial substitution of Al by Si in Al80Mn20 (at.%) binary alloy completely suppresses the formation of a pentagonal quasicrystalline T-phase and drastically modifies the microstructure of the i-phase. Consequently, knowledge of the phase diagram and thermodynamic properties in the Be–Si system is of fundamental importance for guiding the design and processing of Al-based quasi-crystal materials and multi-component commercial Al alloys.The phase relationship in the Be–Si system has been subjected to several investigations [6–10]. This binary phase diagram was shown to be a simple eutectic one. Masing and Dahl [6] are responsible for the major contribution to the establishment of the Be–Si phase diagram. By means of thermal analysis technique, they [6] measured the phase transition temperatures for four bi-