Nanjing University of Aeronautics and Astronautics

About: Nanjing University of Aeronautics and Astronautics is a education organization based out in Nanjing, China. It is known for research contribution in the topics: Computer science & Microstructure. The organization has 33704 authors who have published 37321 publications receiving 438855 citations. The organization is also known as: Nanjing College of Aviation Industry & Nanjing Aeronautical Institute.

A quantitative multidamage monitoring method for large-scale complex composite:

Abstract: Modern structures on aircraft make increasing use of large-scale composite structures. Quantitative damage monitoring for composites, including damage occurrence, number, localization, and size estimation, will help reduce maintenance costs, improve fleet management efficiency through condition-based maintenance, and potentially more rapidly enable new material systems and structural concepts by integrating health monitoring into the design itself. With the advantage of easily interpretable, intuitive, and accurate imaging result, the delay-and-sum imaging algorithm is frequently researched and applied to damage monitoring. However, when it is applied to multidamage monitoring in large-scale composites, the consumed time and computation resource are too much for pixel value calculation. Besides, due to the material anisotropy and existence of bolt holes and stiffeners in the researched complex carbon fiber composite laminate, propagation mechanism of Lamb wave is quite complicated, which makes the convent...

Static analysis of frame structures by the differential quadrature element method

Abstract: In this paper a new version of Differential Quadrature Method (DQM) is proposed and then extended to analyse frame structures. The new method, called the Differential Quadrature Element Method (DQEM), retains all advantages of the earlier version of the differential quadrature method and overcomes some critical shortcomings existing in the original DQM. The proposed method is, however, different from the Quadrature Element Method (QEM) proposed earlier by Striz et al. The methodology is explained in details herein via a differential quadrature beam element and some numerical examples are given to show the efficiency of the present method. © 1997 by John Wiley & Sons, Ltd.

Laser metal deposition of TiC/Inconel 718 composites with tailored interfacial microstructures

Abstract: Laser metal deposition (LMD) was applied to deposit Inconel 718 metal matrix composites reinforced with TiC particles. The influence of laser energy input per unit length on constitution phases, microstructures, hardness, and wear performance of LMD-processed TiC/Inconel 718 composites was studied. It revealed that the LMD-processed composites consisted of γ Ni–Cr solid solution matrix, the intermetallic precipitation phase γ′, and the TiC reinforcing phase. For the laser energy input per unit length of 80–120 kJ/m, a coherent interfacial layer with the thickness of 0.8–1.4 μm was formed between TiC reinforcing particles and the matrix, which was identified as (Ti,M)C (M=Nb and Mo) layer. Its formation was due to the reaction of the strong carbide-forming elements Nb and Mo of the matrix with the dissolved Ti and C on the surface of TiC particles. The microstructures of the TiC reinforcing phase experienced a successive change as laser energy input per unit length increased: Relatively coarsened poly-angular particles (80 kJ/m) – surface melted, smoothened TiC particles (≥100 kJ/m) – fully melted/precipitated, significantly refined TiC dendrites/particles (160 kJ/m). Using the laser energy input per unit length ≥100 kJ/m produced the fully dense composites having the uniformly dispersed TiC reinforcing particles. Either the formation of reinforcement/matrix interfacial layer or the refinement in TiC dendrites/particles microstructures enhanced the microhardness and wear performance of TiC/Inconel 718 composites.

Co3O4 nanoneedle arrays as a multifunctional “super-reservoir” electrode for long cycle life Li–S batteries

Abstract: Lithium–sulfur (Li–S) batteries are highly attractive as energy storage devices due to their low cost and high energy density. The undesired capacity degradation caused by the polysulfide shuttle, however, has hindered their commercialization. Herein, a Co3O4 nanoneedle array on carbon cloth (CC@Co3O4) nanocomposite has been prepared and demonstrated for the first time as a multifunctional “super-reservoir” electrode to prolong the cycle life of Li–S batteries. Owing to the polar surface of the Co3O4 nanoneedle array, soluble lithium polysulfides (Li2Sn, 4 < n < 8) can be effectively absorbed and then transformed to insoluble Li2S2/Li2S which evenly covers the surface of the Co3O4 nanoneedle during the discharge process. Further, during the charge process, the Co3O4 nanoneedle can catalyze the electrochemical transformation of Li2S2/Li2S into soluble polysulfides. A high initial capacity of 1231 mA h g−1 at 0.5C and a slow capacity decay of 0.049%/cycle at 2.0C over 500 cycles were achieved; excellent rate performance was also obtained.