航空材料学报

2018-05-Catalog

2018, 38(5): .

[Abstract](2196) [PDF 1084KB](22)

Abstract:

Progress on Self-Healing and Structure-Wave Absorbing Integration of Silicon Carbide Ceramic Matrix Composites

Xiaokang MA, Xiaowei YIN, Xiaomeng FAN, Laifei CHENG, Litong ZHANG

2018, 38(5): 1-9.

[Abstract](4102) [FullText HTML] (2200) [PDF 786KB](146)

Abstract:
In order to meet the need of high thrust ratio aero engine working in long term thermal oxidation environment and the stealth requirement of key thermal structural components of aero engine, silicon carbide ceramic matrix composites are developed towards crack self-healing and structure-wave absorbing integration. In this paper, the design principles of silicon carbide ceramic matrix composites in strengthening and toughening, crack self-healing and electromagnetic wave absorption are introduced. The research progress in these three aspects is reviewed. The future development trend of structural and functional CMC-SiC is the combination of high strength and toughness, self-healing antioxidation and electromagnetic wave absorption.

Research Progress in Preparation and Mechanical Properties of Nanoporous Metals

Yuanwei LI, Meng ZHANG, Xiaojian WANG, Wei LI

2018, 38(5): 10-23.

[Abstract](3069) [FullText HTML] (1392) [PDF 1414KB](93)

Abstract:
Nanoporous metals are the of porous metal materials with pore sizes ranging from 0.1-100 nm. Because of its unique porous structure, high specific surface area, and high conductivity, nanoporous metals have wide applications in many fields. In this article, several common methods for preparing nanoporous metals are summarized, they are template method, dealloying method and electrochemical method. The dealloying method is mainly introduced, including the recent advances in liquid metal dealloying and gas phase dealloying. The development status and related research work of nanoporous metals in surface-enhanced Raman scattering, catalysis, and supercapacitor are detailed. Finally, through the discussion of the simulations and experiments of the mechanical properties of nanoporous metals,the research trends and main problems of the mechanical properties of nanoporous metals are analyzed. From now on, realizing the 3D performance of materials through microstructure will become the development trend of smart materials. Nanoporous metal is an important material microstructure, and the technology will develop more and more maturely in the future. In the future research of nanoporous metals, the following two directions will receive wide attention: using a prepared nanoporous metal as a template and using a cheaper alloy as a precursor.

Research Progress in Preparation and Crystallization Technologies of Amorphous ITO Film

Jiaming LI, Liangbao JIANG, Mu CHEN, Xiaoyu LI, Youxiu WEI, Xiaofeng ZHANG, Yibo MA, Yue YAN

2018, 38(5): 24-35.

[Abstract](8092) [FullText HTML] (3188) [PDF 813KB](82)

Abstract:
Transparent conductive oxide films have been widely used in liquid crystal displays, solar cells, electrochromic windows, gas sensors, curtain wall glass, heat-transfer glass for aircraft and high-speed trains (de-icing and defogging). The study of its preparation and treatment methods is also crucial and important. In order to prepare a highly transmissive and highly conductive ITO film, it is generally obtained by two methods: a crystalline high-quality thin film is deposited by a high-temperature preparation method directly, and an amorphous film is deposited at room temperature and then heat-treated. However, for substrates that are not resistant to high temperatures, they cannot be exposed to high temperatures for long periods of time. Therefore, it is significant to study the rapid heat treatment crystallization method, aiming at not only ensuring the application requirements of the ITO film, but also reducing the adverse effect of the crystallization method on the substrate. According to different application backgrounds and application requirements, selecting the appropriate preparation method and crystallization method are the key issues to obtaining highly transmissive and highly conductive films. This paper summarizes the current research progress of crystallization methods of ITO transparent conductive oxide films both at home and abroad. By comparing the mechanism, advantages and disadvantages of different thin film crystallization methods, it is found that the infrared annealing, laser annealing, and flash lamp annealing can achieve rapid crystallization of the thin film, and the temperature of substrate is lower than the temperature of film during the process. These methods are expected to replace the conventional furnace annealing crystallization method used in current commercial production for improving production efficiency, saving production costs, obtaining high-quality and high-performance transparent conductive oxide film. These methods are expected to be more widely used.

Research Progress of Acrylonitrile-butadiene Rubber Nanocomposites Filled with Graphene

Huimin DONG, Weiqi MU, Haiyan SHI, Huanghai QIAN, Ming LU, Jia LIU

2018, 38(5): 36-46.

[Abstract](3317) [FullText HTML] (1469) [PDF 724KB](48)

Abstract:
This article summarizes the preparation and functionalization of graphene, and introduces the fabrication methods of graphene/NBR nanocomposites including emulsion blending, solution blending, and mechanical blending. The mechanical properties, cure characteristics, fatigue properties, electrical conductivity, thermal behavior, tribological properties along with gas barrier properties are reviewed. With the further study of the molecular interaction between graphene and NBR, the structure and properties graphene/NBR are gradually perceived. Finally, it is pointed out that the development of graphene/NBR nanocomposites in the fields of medium corrosion resistance, radiation resistance, damping and flame retardancy has more room to be expanded.

Research Progress in Cemented Carbide with Co-Ni-Al Composite Binder Phase

Jianzhan LONG, Yong DU, Bizhi LU, Weibing ZHANG, Tao XU, Zhongjian ZHANG, Maozhong YI

2018, 38(5): 47-58.

[Abstract](7342) [FullText HTML] (2619) [PDF 2617KB](62)

Abstract:
The application background of Co-Ni-Al composite binder phase in cemented carbide was introduced. The latest research results of Co-based superalloy and the properties of cemented carbide with binder strengthened by ordered phase were briefly described. The application of integrated computational material engineering in the research and development of Co-Ni-Al composite binder was introduced. The progress in the preparation, microstructure characterization and performance of WC-Co-Ni-Al cemented carbides were summarized. The results show that the composition of Co-Ni-Al composite binder has obvious influence on the solid-liquid interface energy and the liquid-phase nucleation driving force of the alloy. Accordingly, the grain size of the binder phase and the grain morphology of WC are affected. Ultimately these factors affect the performance of the alloy. It is pointed out that the performance of cemented carbide strengthened by ordered γ′ phase precipitation can be improved significantly. It is expected to obtain high-performance cemented carbide materials with excellent high-temperature resistance, corrosion resistance and oxidation resistance. It is proposed that the interfacial microstructure, the relationship between C content and precipitation phase and the anti-wear mechanism of cemented carbide with Co-Ni-Al composite binder phase should be emphasized in future.

Preparation and Properties of Laminated Bionic High-strength Composites of B₄C Ceramic/Al

Hanbing WANG, Lishi WANG, Jian ZHANG, Yunhong LIANG, Zhihui ZHANG

2018, 38(5): 59-66.

[Abstract](2911) [FullText HTML] (1353) [PDF 1169KB](26)

Abstract:
Based on the laminar composite structure, the hardness distribution pattern and crack arrest property of Rapana venosa shell, bionic layered composite materials were prepared via hot-pressing sintering by using B₄C/5083Al system and pure 5083Al as materials. The microstructure and mechanical properties were investigated by scanning electron microscope (SEM) and universal tester. The results show that on the macroscopic level, the bionic layered composite material has a multi-layered structure which is composed of hard layer of B₄C/5083Al and flexible layer of 5083Al. The bionic composites exhibit " soft and hard” distribution characteristic of hardness. On the microscopic level, the hard layer of B₄C/5083Al consists of B₄C and 5083Al matrix, and B₄C is staggered and interlinked in 5083Al matrix with combination of "soft and hard" properties. The bionic layered composites own higher compressive strength and impact toughness, and the layered overlapping structure can reset the direction of crack in the next layer, which lead the crack deflection phenomena and high impact resistance.

Microstructure and Properties of a Low-Density Steel with High Strength of 1350 MPa

Zhihua JIANG, Jianjun JIN, Xiaozhen WANG, Chunwen HU, Zhiming NI

2018, 38(5): 67-73.

[Abstract](3675) [FullText HTML] (1411) [PDF 1342KB](24)

Abstract:
A low-density steel Fe-20Mn-10Al-1.0C with high strength of 1350 MPa was developed. The mechanical properties and microstructure evolutions of Fe-20Mn-10Al-1.0C steel under various heat treatment conditions were investigated by means of optical microscopy, X-ray diffraction and high resolution electron microscopy. The results show that the alloy goes through spinodal decomposition leading to the L′1₂ ordered phase-κ′ carbide (Fe, Mn)₃AlC_x formation. After solution-treatment at 950 ℃, diffused precipitates of (Fe, Mn)₃AlC_x with the sizes of 2-5 nm are formed inside the austenite substrate. After the subsequent ageing process, the size of κ′ carbides is increased, and the particles tend to be aligned and agglomerated along the <100> directions with the aging temperature increases. Periodic modulated structures are finally formed into resembling regular "checkered lattice". Ordering effect strengthening by the nano-sized κ′ carbides and elastic misfit strengthening by spinodal decomposition cause a high tensile strength up to 1350 MPa with a good elongation, and the density is lower than 6.80 g/cm³.

Microstructure and Mechanical Properties of ZrC-TaC Ceramic Prepared by Hot Pressing Sintering

Yan ZHANG, Yingkui GUO

2018, 38(5): 74-79.

[Abstract](3582) [FullText HTML] (1548) [PDF 1664KB](37)

Abstract:
Zirconium carbide which is a kind of ultra high temperature ceramics has broad application prospects in the aerospace, nuclear technology, electronics and other fields. In order to improve the sintering properties and mechanical properties of ZrC ceramics, using ZrO₂ powder and TaO₂ powder as raw materials, TaC and ZrC solid solution powder were prepared by carbon thermal reduction, and the hot pressing sintering process was used to prepare ZrC-TaC ceramics. The effect of the sintering temperature on the solid solution behavior, densification behavior, tissue structure and mechanical properties was studied. The results show that the TaC in ZrC solid solubility is enhanced when the temperature is increased from 2000 ℃ to 2050 ℃.When TaC content is increased from 5% to 15%, the density of the composite, vickers hardness, fracture toughness and elastic modulus are decreased monotonously, and the bending strength has no apparent rule.

Formation Mechanism and Restraining Measures of Burning-on of DZ22B Directionally Solidified Blade

Fei LI, Xiaoyan CHEN, Yanjie ZHAO, Fei WANG, Baode SUN, Dongke SUN, Zhenfeng LI

2018, 38(5): 80-87.

[Abstract](2859) [FullText HTML] (1528) [PDF 1161KB](28)

Abstract:
The microstructure and chemical composition of the burning-on layer of the directionally solidified blade of the DZ22B superalloy were studied by means of SEM and EDS. The results show that the metal ceramic like sand defects are formed by a part of ceramic particles covered during the infiltration of metal to shell surface pores. The main component of the burning-on layer composes fused corundum, with some interfacial reaction products containing Cr₂O₃ and HfO₂. According to the results of SEM analysis of blade cross section, the mechanism of the burning-on of the DZ22B directionally solidified blade is mainly caused by thermo mechanical permeation. A certain amount of burning-on inhibitor is added to the shell surface slurry, which significantly improves the penetration resistance of the fused corundum shell surface. The casting verifies that the surface of the DZ22B directionally solidified blade is smooth without burning-on, and the metallic luster on the blade surface is obviously observed.

Precipitate Phases of Electron Beam Welded Joint in Superalloy Dissimilar Materials

Jin LIU, Zhiyi ZHAO

2018, 38(5): 88-95.

[Abstract](2798) [FullText HTML] (1460) [PDF 1387KB](27)

Abstract:
The precipitate phases of electron beam welded joint in GH141/GH907 superalloy dissimilar materials were studied by scanning electron microscopy (SEM), transmission electron microscope (TEM) and energy dispersive spectrometer (EDS). The welded joint contains GH141 heat affected zone, GH907 heat affected zone and weld area. The results indicate that there is no new precipitate phase in the heat affected zones of electron beam welding. Under the current heat treatment process, the precipitate phases of GH141 heat affected zone are square granular γ′ phases which are covered in matrix densely, thick massive MC type carbides with random distribution and the M₆C type carbides which are precipitated mostly in the grain boundaries. Precipitate phases of GH907 heat affected zone are needle shaped ε phases covered in matrix densely and block G phases Nb₃Ni₂Si which are dispersed distribution. Precipitate phases of weld area are different from the two kinds of welding materials. One of them is a new needle shaped phase which has parallel or staggered distribution, and the other one is a tiny square or ellipsoid granular new precipitate phase which is proved to be orthogonal crystal system NbTi₄ phase.

Rare-earth Element doped YSZ/YSZ Multilayer Thermal Barrier Coating with High Infrared Reflectivity

Wei YANG, Yufeng WANG

2018, 38(5): 96-101.

[Abstract](3116) [FullText HTML] (1571) [PDF 1072KB](36)

Abstract:
The operating temperature of advanced aeroturbine engine increases rapidly for higher working efficiency. Thermal barrier coatings (TBCs) with high temperature capability and thermal insulation effect are required. In this work, a novel multilayer TBCs consisting of rare-earth element doped YSZ and YSZ sublayers were designed and fabricated. The influence of microstructure to the phase structure, thermal conductivity and infrared reflectivity of the coatings were investigated. The results show that a preferred orientation of (200) is yielded in the coating. With the increase of layers, the thermal conductivity of the coating decreases and the infrared reflectivity increases respectively. The multilayer coating with 200 sublayers exhibits a thermal conductivity of 1.1-1.16 W/m·K, 11% lower than that of the conventional single layer coating. The infrared reflectivity of the coating reaches as high as 48%-55%.

Prediction for Contact Fatigue Life of Plasma Sprayed Coating Based on Weibull Distribution

Xiaoyu FEI, Guolu LI, Haidou WANG

2018, 38(5): 102-107.

[Abstract](2626) [FullText HTML] (1336) [PDF 682KB](19)

Abstract:
Weibull distribution is one of the most common statistical methods used to deal with and analyze the fatigue life, but in the study of contact fatigue life of coating, most scholars established the Weibull distribution model without multivariate statistical analysis, which affected the accuracy of the model to a certain extent. In this work, NiCrBSi alloy coating was deposited on steel (AISI 1045) substrate using supersonic plasma spraying technique. Rolling contact fatigue (RCF) life of the coating was investigated using a ball-on-disc tester under different loads. The contact fatigue life of the coating was verified by Fan-Montfort test. The results show that the RCF life of different loads accords with Weibull distribution. The map of Weibull distribution failure probability is plotted. The coating failure probability at any number of cycles under the same working conditions can be observed intuitively through the map. The regression equation of RCF life and loading is established, it shows that the logarithm of characteristic life is linear associated with the loading, and the regression model can accurately characterize the contact fatigue life of coatings in a certain range.

Comparative Dynamic Analysis on Different Corrosion Damage Characterizations of ZL105 in Immersion Environment

Guangyao YAN, Zhiguo LIU, Tao LIU

2018, 38(5): 108-115.

[Abstract](2985) [FullText HTML] (1205) [PDF 884KB](13)

Abstract:
Corrosion damage has a severe impact on security and reliability of the aircraft components. It is worthy to study environment suitability of the materials for planes transferring along the coast annually. The corrosion damage of the aluminum alloy ZL105 in the corrosive immersion environment was studied by referring to the environment parameters of the accelerated corrosion test spectrum. In order to obtain the average pitting depth and surface self-corrosion current density, the corrosion damage morphology was observed and electrochemical measurements after every immersion cycle were carried out. By fitting analysis, corrosion dynamics curves of corrosion rate symbolized by average pit depth and surface self-corrosion current density were acquired. Meanwhile, a quantitative comparison was implemented to analyze change rules of the two corrosion rates by using non-dimensional normalization, and it was figured out that the two normalized corrosion rates had a significant correlation and the correlation parameter was 0.969. Differences of the two curves were reasonably explained according to ZL105 corrosion damage morphology observations and the relevant mathematical pitting model.

Effect of Surface Treatment on Durability of GFRP Reinforced Aluminum Structure under Hygrothermal Environment

Zhouhui YU, Peizhong ZHAO, Fangyou HU

2018, 38(5): 116-122.

[Abstract](2932) [FullText HTML] (1418) [PDF 1520KB](22)

Abstract:
The aluminum alloy surface was treated through three different processes. The bonding strength of GFRP-aluminum under hygrothermal environment with different surface treatments was tested and was arranged with the order of anodizing > silane coupling agent > sand blasting. The effects of hygrothermal environment and surface treatment on repair effects were also studied by tensile tests of GFRP and GFRP reinforced aluminum. The results show that the tensile strength, elastic modulus and break elongation of GFRP decrease after wet and heat treatments. After different surface treatments, the initial loads of repaired specimens increase with the order of anodizing > silane coupling agent > sand blasting. The bearing capacities of the specimens repaired by different surface treatments are reduced to different degrees under hygrothermal environment. For sand blasting specimen, the declining of bonding strength of the resin-aluminum is the main cause of the declining of bearing capacity, and damage mainly occurs in the interface. For the silane coupling agent and anodic specimen, damage occurs mainly in the resin-GFRP interface, the mechanical property of resin-aluminum interface is better than that of resin-GFRP.

Influence of Electrical Conductivity of Composites on Ablation Damage Degree Subjected to Lightning Strike

Yao XIAO, Shulin LI, Yuqian WANG, Fei CHANG, Junjie YIN

2018, 38(5): 123-131.

[Abstract](2962) [FullText HTML] (1283) [PDF 1268KB](25)

Abstract:
According to the energy conversion relationship during the lightning strike, a lightning damage analysis model based on coupled electrical-thermal simulation for composites was established. The variation of electrical conductivity of the composite with pyrolysis was considered in the model. By means of the model, the lightning ablation damage of the composite material with multiple changes of conductivity was compared in three directions. The results show that under the same lightning current parameters, the electrical conductivity changes of composite materials in different directions have different effects on the ablation damage caused by lightning strikes. When the electrical conductivity along the fiber direction increases, both the apparent damage area and the damage depth decreased. While the electrical conductivity perpendicular to the fiber direction increases, the apparent damage area increased and the damage depth decreased. When the electrical conductivity along the thickness increases, the apparent damage area increased and the damage depth increased. When the conductivity along any of the three directions increases , the total damage volume of the composite decreased. When the conductivity of each direction increases by 1, 2, 3 orders of magnitude, the greatest changes in damage volume are observed along the fiber direction, which are decreased by 47.83 %, 75.08 % and 97.82 % respectively, followed by changes along the thickness direction, which are decreased by 36.25 %, 53.44 % and 65.54 %, and the least changes are perpendicular to the fiber direction, which are reduced by 8.72. %, 12.58 % and 24.76 %. The increase of the conductivity of the composite material play a significant role in lightning strike protection. A comprehensive assessment of the lightning protection effect requires a combination of two-dimensional damage and three-dimensional damage.

Effect of Impact Damage and Open Hole on Typical Mechanical Properties of CYCOM 7701/7781 Fiberglass Epoxy Composite Lamina

Qingyu GUAN

2018, 38(5): 132-137.

[Abstract](2911) [FullText HTML] (1421) [PDF 533KB](25)

Abstract:
CYCOM 7701/7781 fiberglass epoxy fabric prepreg was used to fabricate the composite lamina specimens through medium temperature curing process. The specimens were categorized into three groups. The tensile strength of unnotched and open-hole specimens, the compressive strength of unnotched and open-hole specimens, and the compressive strength after impact were respectively tested under three conditions of cold temperature dry (CTD), room temperature dry (RTD), and elevated temperature wet (ETW). The effects of impact and open hole on typical mechanical properties of CYCOM 7701/7781 composite lamina were studied. The results show that the open-hole makes the average tensile strength decrease by about 50% under the CTD, RTD and ETW conditions, and decreases the coefficients of variation of the tensile strength. Impact damage and open-hole have similar disadvantageous effects on the average compressive strength under CTD and RTD environment conditions, which decrease the average compressive strength by about 45%-55%, while the impact damage and open-hole have different effects on the compressive strength under ETW condition. The compressive strength is decreased about 50% by the open-hole and about 30% by the impact damage under ETW condition. It is indicating that the effect of open-hole condition is more severe than that of impact damage condition under ETW condition.

Progressive Damage Based Failure Analysis of Open-hole Composite Laminates under Tension

Rupeng LI, Lei CHEN, Xueshu LIU, Xiangqian ZENG, Hang GAO

2018, 38(5): 138-146.

[Abstract](3877) [FullText HTML] (1975) [PDF 1462KB](53)

Abstract:
To investigate the failure behavior of open-hole carbon fiber reinforced plastics (CFRP) under the circumstance of tensile loading, three-dimensional Hashin failure criteria was adopted to predict damage initiation, and a stiffness degradation method based on progressive damage theory was proposed to assess the damage evolution. The subroutine UMAT was developed to numerically analyze the loading capacity and failure behavior of open-hole CFRP laminates under tension. The numerical prediction of ultimate loading capacity and failure procedure are compared with the experimental data, and the results are indentical. Therefore, the effectiveness and accuracy of the proposed method are validated.

Impact Resistance of T800 Carbon Fiber Composite Materials

Li WANG, Shu XIONG, Yan ZHAO, Li YANG

2018, 38(5): 147-152.

[Abstract](3023) [FullText HTML] (1462) [PDF 938KB](50)

Abstract:
The properties such as dent depth, residual compressive strength and compressive failure strain of 3 groups of T800 carbon fiber composite laminates with the same layer ratio and different thicknesses were tested. The results show that there inflection points are existed both in impact energy-dent depth curves and dent depth-residual compression strength curves. The inflection points of the 3 groups are at the depths of 0.70 mm, 0.76 mm and 0.45 mm respectively, which are less than the depth of dent (1.3 mm) corresponding to barely visible impact damage (BVID). With the same ply ratio, the greater the thickness of composite laminates, the better the impact damage resistance.

2018 Vol. 38, No. 5