The thermo-mechanical response of micro-architectured tungsten coatings is characterized in the temperature range of 293 to 673 K using both in situ micro-compression experiments inside a scanning electron microscope (SEM) as well as image-based crystal plasticity finite element method (CPFEM) simulations. The experiments were conducted on micropillar-like specimens that were focus ion beam milled into the coatings, while the simulations were conducted on columnar-grained micropillar simulation cells constructed based on the statistics of the coating’s microstructure. The experimental results show that the stress–strain response and deformation mode exhibit a strong temperature-dependence. At room temperature, catastrophic failure is observed shortly after yield and is manifested in the form of intergranular fracture and buckling of individual columnar grains. With increasing temperature, this catastrophic failure is gradually suppressed and the material exhibits a steadier strain hardening response at 693 K. The CPFEM simulations are also shown to be in good agreement with the experimental results, and these simulations indicate that the material response is strongly influenced by the local crystallographic anisotropy and microstructure inhomogeneity. Furthermore, the simulations capture the underlying mechanisms that control the temperature-dependent transition in deformation mode. The current results highlight that the micro-architectured microstructure offers a great combination of excellent mechanical strength and structural integrity at elevated temperatures, which is of importance for high temperature applications.

微结构钨涂层的热机械响应特征是在293至673 K的温度范围内使用两种原位扫描电子显微镜（SEM）内的微压缩实验以及基于图像的晶体可塑性有限元方法（CPFEM）模拟。实验是在聚焦离子束铣削成涂层的类微柱状试样上进行的，而模拟是在基于涂层微结构统计数据构建的柱状晶粒微柱状模拟单元上进行的。实验结果表明，应力应变响应和变形模式表现出强烈的温度依赖性。在室温下，在屈服后不久就观察到灾难性的破坏，并表现为晶间断裂和单个柱状晶粒屈曲的形式。随着温度的升高，这种灾难性的破坏逐渐得到抑制，材料在693 K时表现出更稳定的应变硬化响应。CPFEM模拟也与实验结果非常吻合，这些模拟表明材料响应受到局部晶体学的强烈影响。各向异性和微观结构的不均匀性。此外，仿真还捕获了控制变形模式下与温度有关的过渡的基本机制。当前结果表明，微结构微结构在高温下具有出色的机械强度和结构完整性的良好组合，这对于高温应用至关重要。这些模拟表明，材料响应受局部晶体各向异性和微观结构不均匀性的强烈影响。此外，仿真还捕获了控制变形模式下与温度有关的过渡的基本机制。当前结果表明，微结构微结构在高温下具有出色的机械强度和结构完整性的良好组合，这对于高温应用至关重要。这些模拟表明，材料响应受局部晶体各向异性和微观结构不均匀性的强烈影响。此外，仿真还捕获了控制变形模式下与温度有关的过渡的基本机制。当前结果表明，微结构微结构在高温下具有出色的机械强度和结构完整性的良好组合，这对于高温应用至关重要。