超高温陶瓷材料极端环境下塑性力学性能测试技术与表征方法

Ultra-high temperature ceramics（UHTCs）have great application potential in aerospace field and other fields, owing their excellent performance such as high temperature resistance , oxidation resistance and low thermal conductivity. While, it incapable to effectively evaluate and predict the mechanical properties of materials in high temperature environment. Especially the plastic mechanical behavior of ceramic material is not clear, which seriously limiting its engineering applications. To solve these problems, systematic research are carry out in this project. Firstly, plastic deformation measurement methods and characterization methods are established. Secondly, the micro-mechanism model is established to describe the plastic deformation of UHTCs. Based on these measurement methods the effect of the temperature and loading rate on plastic deformation are researched. In the end, the theoretical models are established, which can effectively describe the temperature-dependent strength model and plasticity constitutive relation of UHTCs. Meanwhile, in this project we will provide a new plastic deformation measurement method of ultra-high temperature ceramic materials, which is beneficial to the experimental study of high temperature mechanical properties of UHTCs. At the same time, the established mechanical model can be used as physical model in simulation research method. Thus, this project will effectively promote the research on UHTCs.

超高温陶瓷材料具有耐高温、抗氧化、低热导率等优异性能，在航空航天等领域具有巨大的应用前景。但目前还不能有效评价和预测陶瓷材料在高温环境下的力学性能，特别是陶瓷材料发生高温塑性变形时的力学行为还不明确，严重限制了其工程应用。为此，本项目首先建立其在高温环境下的塑性变形测量手段及表征方法，并基于该方法建立超高温陶瓷材料发生塑性变形的微观机制模型；然后，开展温度及加载速率等主要因素对塑性变形影响的研究工作；最后，建立能够有效描述和预测超高温陶瓷材料破坏的温度相关性强度模型和塑性本构模型。开展本项目有望提供一种针对超高温陶瓷材料塑性变形的测量及表征方法，为超高温陶瓷材料高温力学性能实验研究提供新的技术手段；同时建立的力学模型能够为陶瓷材料高温力学性能的数值模拟方法提供物理模型，将有效地推动超高温陶瓷材料的研究进展。

本项提出了逆序计算、分块匹配和基于应变片导向的偏导径向基算法相结合的方法进行应变计算，提高非接触变形测量精度；探索了激光涂覆加热的热场分布情况，并发展了针对超高温陶瓷的激光切割技术，在试验标表征方面通过试验测试的方法研究了几种典型的陶瓷材料包括ZrB2-SiC，多孔Yb2SiO5超高温有氧环境下的力学性能，建立超高温陶瓷材料在不同温度下的断裂强度及本构模型；建立了考虑氧化反应对陶瓷材料温度相关性力学性能预测模型；提出了一种只需四组试验即可有效预测材料的韧脆转变温度的方法。通过本项目在试验方法、高温陶瓷实验研究数据及理论研究结果为超高温陶瓷在关键耐热部件上的应用推广提供有益参考。本项目资助发表论文4篇，培养硕士研究生1名。项目投入经费28万，支出272,747.79元 ，各项支出基本与预算相符。剩余经费0.7252.21万元，剩余经费计划用于本项目研究的后续支出。