EAGER: Composites with Constrained Phase Transforming Ceramic Inclusions

该项目探索了一个全新的、高度新颖的范例，由PI发明，用于创造新材料，这些材料表现出远远超过任何先前已知材料所表现出的实际重要的机械性能。这种特性的例子是刚度（在负载下抵抗变形的能力）和阻尼（消散振动和声音的能力）。发起人的初步理论研究表明，这种方法具有巨大的潜力，他们的初步实验研究表明，按照这种新范式创建的研究样本的刚度是以前已知的最硬材料钻石的十倍。该范例涉及将一种本身不稳定的材料嵌入另一种稳定的材料中，并仔细调整两种材料的特性，以便最终组合的材料显示出所需的极端特性。目前的研究旨在提供必要的进一步的理论和实验科学进展，以证实这种新型材料确实具有广泛应用的潜力。这项研究很重要，因为所涉及的范式在所有现有方法中具有最大的潜力，可以显着改善材料的多种机械性能。它的潜在影响远远超出了要进行的具体工作，因为利用有限制的不稳定的想法很可能导致以前在许多其他领域无法实现的制度。这项工作也具有重要的教育意义，因为它向学生展示了通过批判性思维实现看似不可能的潜力。技术细节：提议的工作建立在最近的理论和实验突破的基础上，这些突破表明含有负刚度相的复合材料：(1)理论上预测具有刚度，阻尼和压电性能远远超过任何已知材料；(2)可以被证明是整体稳定的，因此可以避开过去半个世纪以来一直被认为限制复合材料性能的整体材料响应边界，因为这些边界假设所有组件材料必须具有正刚度；(3)可以用部分约束的相变陶瓷夹杂物来制造，并且在实验室测试中可以显示出其刚度是金刚石的十倍，阻尼大大超过任何一种相。该研究涉及理论稳定性和复合材料行为分析与实验室制造和测试的密切协调。该项目的目标是扩展提议器在应变、温度和稳定性方面的稳健性和操作范围。初步的实验室复合材料由金属基体中的部分受限相变陶瓷夹杂物组成，并为这种新型材料创造方法的有效性和实用性提供了令人信服的额外理论和实验证实。这项研究是重要的，及时的和潜在的变革，因为它涉及到一个全新的和新颖的材料创造范式，并且pi不知道任何其他材料创造范式具有如此巨大的材料性能改进的潜力，特别是如此重要的，多样的和众多的性能，如刚度，阻尼和压电性（很可能还有几个额外的）。人们认为，这种迫切需要的支持将产生令人信服的理论和实验证据，证明所创造的材料可以在使其广泛适用的条件下加以利用。该项目还具有多个重要的教育方面：从广义上讲，它将教会学生通过批判性的跳出思维来实现看似不可能的潜力。此外，直接参与该项目的本科生和研究生将学习全新的研究技术，包括使用调谐约束亚稳态的思想来创建材料。

NON-TECHNICAL DESCRIPTIONThis project explores a completely new and highly novel paradigm, invented by the PI, for the creation of new materials that exhibit practically-important mechanical properties far in excess of those exhibited by any previously-known materials. Examples of such properties are stiffness (the ability to resist deformation under load) and damping (the ability to dissipate vibration and sound). Preliminary theoretical studies by the proposers indicate the great potential of this approach, and their preliminary experimental studies have shown that a research sample created following this new paradigm exhibits stiffness ten times that of diamond, the previously-known stiffest material. The paradigm involves embedding a material that would be unstable by itself in another, stable material and carefully tuning the properties of the two materials so that the resulting combined material exhibits the desired extreme properties. The present research is directed toward providing the necessary further theoretical and experimental scientific advances needed to confirm that such novel materials do indeed have the potential for wide utility. This research is important because the paradigm involved has the greatest potential of all existing approaches for dramatically improving multiple mechanical properties of materials. It has potential impact far beyond the specific work to be carried out, because the idea of employing constrained instability could well lead to regimes previously inaccessible in many other fields. The work also has great educational importance, in that it demonstrates to students the potential for achieving the seemingly impossible by critical outside the box thinking.TECHNICAL DETAILSThe proposed work builds on recent theoretical and experimental breakthroughs by the proposers which showed that composite materials containing a negative-stiffness phase: (1) are theoretically predicted to have stiffness, damping and piezoelectric properties far exceeding those of any known material; (2) can be proved to be stable overall, and thus can evade the bounds on overall material response that have been believed for the past half-century to limit composite material performance, since these bounds assume all component materials must have positive stiffnesses; (3) can be fabricated using partially-constrained phase-transforming ceramic inclusions and can be shown in laboratory testing to exhibit stiffness ten times that of diamond and damping greatly exceeding that of either phase. The research involves close coordination of theoretical stability and composite material behavior analyses with laboratory fabrication and testing. The goals of the project are to extend the robustness and operational range, in strain, temperature and stability, of the proposers? preliminary laboratory composite materials comprised of partially-constrained phase-transforming ceramic inclusions in a metal matrix, and to provide convincing additional theoretical and experimental confirmation of the validity and utility of this novel material creation approach. This research is important, timely and potentially transformational because it involves a completely new and novel material creation paradigm, and the PIs are unaware of any other material creation paradigm having such potential for dramatic improvement in material properties, and especially such important, diverse and numerous properties as stiffness, damping and piezoelectricity (and very possibly several additional ones). It is thought that this EAGER support will result in convincing theoretical and experimental evidence that the materials created can be utilized under the conditions that would give them wide applicably. The project also has multiple important educational aspects: broadly, it will teach students the potential for achieving the seemingly impossible by critical outside the box thinking. Furthermore, the undergraduate and graduate students working directly on the project will learn completely novel research techniques involved with creating materials employing the idea of tuned constrained metastability.