石墨烯纳米片(GnPs)和膨胀石墨(EG)作为轻质高导热碳材料被用于增强棕榈酸-硬脂酸(PA-SA)相变材料的热性能。以聚乙烯吡咯烷酮作为分散稳定剂,通过混溶共混和超声处理方法制备了GnPs和EG的含量分别为1wt%,2wt%,4wt% and 8wt%的PA-SA/GnPs和PA-SA/EG复合相变材料。扫描电子显微镜和傅里叶红外光谱表征了GnPs,EG和复合相变材料的微观和化学结构。
分段式风电叶片是解决长叶片运输和制造困难的有效方案,本文综述了分段式风电叶片相关的基础研究和技术发展概况,分析了大型复合材料分段式叶片的连接构造特点和技术优势,展望了分段式风电叶片技术和应用发展趋势,同时介绍了中科院工程热物理所在风电叶片技术研究的最新进展。
从实验及数值模拟两个方面研究梯度波纹缺陷对复合材料层合板刚度影响。采用VARI成型工艺制作复合材料梯度波纹板试样,通过压缩测试测得其杨氏模量和泊松比,并观察试样的失效形式。利用有限元分析软件ANSYS构建复合材料梯度波纹板模型,预测复合材料波纹板的刚度,研究波纹比对刚度的影响。研究结果表明:梯度波纹对复合材料的刚度影响较大,尤其是Ex的下降趋势非常明显,在轴向压缩载荷作用下,试样首先发生分层破坏,
基于ABAQUS有限元分析软件,对受轴向压缩的开口复合材料曲壳、圆柱壳进行渐进失效分析。采用三维Hashin准则和Ye准则作为层合板纤维损伤、基体损伤、分层损伤开始的判据,并以基于连续介质损伤力学的非线性刚度退化模型模拟材料损伤的演化过程。此渐进失效模型通过编写用户材料子程序UMAT实现。分析了开口附近纤维损伤、基体损伤、分层损伤的开始与扩展过程。数值模拟结果与试验结果对比,最终失效载荷误差小于1
将智能材料黏贴在叶片表面或嵌入叶片内部形成新的结构,智能材料作为传感器和作动器,通过机电耦合抑制叶片的振动.在压电陶瓷第一压电方程的基础上,把风电叶片简化成柔性悬臂梁,仿真所用悬臂梁的弹性模量为Eb=7×109 Pa,密度ρb=1600kg/m3,其几何尺寸为长度Lb=0.5m,宽度b=0.024m,厚度tb =0.002m,建立了压电智能悬臂梁状态空间的动力学模型,针对此系统利用最优控制理论进行
X-ray Computed Tomography (XCT) is a powerful technology that can accurately image the internal structures of composite and heterogeneous materials in three-dimensions (3D).We report in this study thr
The additives of carbon nano-particles may improve properties of carbon fibber-reinforced composites (CFRCs).So, it is very important for material and property researches as well as structural manufac
Sandwich composites are widely utilized in various environments and applications.In-service and environmental stresses can cause unwanted defects such as impact damage, crushed core, skin missing, dis
Composite stiffened-structure consists of the skin and stringer has been widely used in aircraft fuselage and wings.Due to the complexity of the structure, the insufficient of curing pressure led to c
Quantitatively detecting crack defects in thermal carrier coatings (TBC) materials using often presents a challenge for the traditional nondestructive testing methods due to the properties of porosity