Exploitation of new materials processing in a mega-gravity field
Exploitation of new materials processing in a mega-gravity field
复制标题
超重力场新材料加工开发
DOI：
10.1016/s0094-5765(00)00150-8
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发表时间：
2001
影响因子：
3.5
通讯作者：
T. Mashimo
中科院分区：
文献类型：
--
作者：
T. Mashimo
强加速场（兆重力）可以导致甚至原子的沉降，并预计会产生独特的一维晶体应变状态，即多组分凝聚态中分子或晶体状态的不稳定性。然而，在巨重力场下的材料科学研究目前尚未得到开发，而微重力已在许多领域得到了广泛的应用。我们发展了凝聚态物质中原子沉降的自洽理论，以及在高温下产生超过100万（1×106）g加速度的超离心装置。最近，我们首次通过原子的沉积形成了原子尺度的梯度结构，并观察到在兆重力场下合金中的晶体生长。人们期望，兆重力的可用性可能会为我们提供新的和强大的选择，在材料加工方面的控制组成，甚至同位素，形成原子尺度的梯度结构或非化学计量结构，并控制原子或分子的有序性。
A strong acceleration field (mega-gravity) can cause the sedimentation of even atoms and is expected to create an unique one-dimensional crystal strain state, i.e. an instability in molecular or crystalline state in multi-component condensed matter. However, materials science research under the mega-gravity field has now remained unexploited, while microgravity has been much used in many fields. We developed a self-consistent theory for sedimentation of atoms in condensed matter, and an ultracentrifuge apparatus to generate an acceleration of over 1 million (1×106)g at high temperature. Recently, we for the first time formed an atomic-scale-graded structure by the sedimentation of atoms, and observed crystal growth in an alloy under a mega-gravity field. It is expected that the availability of mega-gravity may offer us new and powerful options in materials processing in terms of controlling compositions even of isotopes, of forming atomic-scale-graded structure or nonstoichiometric structure, and of controlling the ordering of atoms or molecules.