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Graphene is a kind of two-dimensional atomic crystal with one atomic layer, which is the basic structure unit of other dimensions of graphite materials, such as zero dimensional fullerenes, one-dimensional carbon nanotubes and three-dimensional graphite. Graphene has a lot of unique electronic and mechanical properties, which have attracted high attention of many scientists in the field of chemistry, materials and other fields. Raman spectroscopy as a sensitive and convenient characterization method, has played a very important role in the study of graphene. Raman spectroscopy is an integral part of graphene research. The application of Raman spectroscopy in graphene characterization in recent years is reviewed in this paper. The characteristic peak of monolayer graphene was first intnduced. Then, through the analysis of the changes of D peak, G peak and 2D peak intensity, position and half peak width of Raman spectra, the number of graphene layers can be quickly and accurately characterized, as well as, the stacking orders, edge chirality and doping degree of graphene were defined. At the same time, the effects of substrate, doping, temperature and laser power on the intensity, position and half width of D peak, G peak and 2D peak of Raman spectra in the process of preparing graphene were also systematically analyzed.

Thermal management systems, controlling the dispersion, storage and conversion of heat, were widely used in various fields of national economy and defence applications etc. Advanced thermal management materials form the material basis of the thermal management system, while the thermal conductivity was the critical property of all the thermal management materials. The application, classification, and physical mechanism of heat conduction of advanced thermal management materials were reviewed in this paper. The research progress and existing problems of thermal interface materials, high thermal conductivity packaging materials, thermal storage materials and thermoelectric materials were introduced. It is pointed out that molecular dynamics, density functional theory and large-scale parallel computing technology will play increasingly import roles in revealing the multi-scale heat transfer mechanism in the homogeneous and composite materials.

There is a growing interest in the application of graphene-based nanocomposites in light-driven technology. Graphene has excellent physical chemical properties, especially the high specific surface area, thermal conductivity and mechanical strength, promoting the development of light-driven technology in remote control intelligently. The light-driven actuator based on graphene nanocomposites provides a kind of bright-future driving technology for precision machinery and optical fields and etc. By reviewing recent advances based on light-driven technology of graphene-based nanocomposites, this paper aims to prospect the research focus on its synthesis method and the ability of graphene to be a filler in light-driven composite and the application prospect in the field of bionic study, micro-robot and biomedical.

Silicate clay minerals possess unique chemistry compositions, micro morphology structures, and physicochemical properties, which make them useful in a broad application in antibacterial fields. Through chemosmosis, some antibacterial elements in silicate clay minerals can directly react with the cell membrane and cytoplasm. By controllable adjustment of the surface charge, silicate clay minerals can be adsorbed to the surface of the bacteria and release the antibacterial agents with controllable amount. The micro morphology structures enable silicate clay minerals to serve as a matrix to load the antibacterial inorganic and organic materials, which can improve the antibacterial effects and undermine the bio-toxicity to prepare the antibacterial nanocomposites with high stability, strong and durable antibacterial effect. The two antibacterial mechanisms of silicate clay minerals including chemiosmosis and physical absorption were reviewed in this paper, the synergistic effects and antibacterial product applications of antibacterial nanocomposites based on silicate clay minerals were further discussed to explore the feasibility of silicate clay minerals in industrial applications of the antibacterial fields.

B4CP/PI polyimide composite films with different powder contents and thicknesses were prepared by particle surface modification and wet mixing machinery-thermal imidization method, using high temperature polyimide as matrix and micro-sized boron carbide (B4C) as thermal neutron absorption material. The thermal neutron radiation shielding property, thermal stability and mechanical property of B4CP/PI polyimide composite films were mainly discussed in this paper. It is shown that the micro-sized B4C functional particles can be well dispersed in PMDA-ODA polyimide matrix, and the thermal stability of B4CP/PI polyimide composite films are significantly improved with the increase of B4C content. However, the mechanical properties of the composite films present the opposite trend; meanwhile, the B4CP/PI polyimide composite films exhibit excellent thermal neutron radiation shielding properties, and the neutron permeability I/I0 presents exponential relationship with the increasing thickness of composite and B4C filler particle content. Therefore,through structural design of the materials,the applications requirements in different fields for materials with high temperature resistant and thermal neutron radiation shielding properties can be met.

Perovskite solar cells(PSCs) have been developed rapidly as one of the most remarkably growing photovoltaic technologies in the last five years. The power conversion efficiency(PCE) of the solar cells has been unprecedentedly increased over the relatively short period. It is of great significance to study the perovskite materials in this kind of solar cells for improving the efficiency. The most focused issues as well as the main progress in varied fabrication techniques and synthesis of new materials in recent years were reviewed in this paper. The characteristics and improvements of varied fabrication techniques are introduced in detail, the necessity and the problems facing for new materials synthesis were analyzed. Finally, a perspective view on reducing the toxicity of perovskite, preparing large-scale perovskite solar cells, and the cost reduction was given to provide the direction for the future research of high-efficiency and stable perovskite solar cells.

The special functions of surface morphology in nature have attracted many scholars' interest, and the control of soft-rigid composites has become a hotspot in recent years. The common soft material surface morphological formation methods, including pre-stretched method, heat treating method and swelling method, were introduced in this paper and a way for the generation of surface morphology was provided. The application of surface morphology in engineering including fluid dynamics, optics, and other fields were introduced, and some ideas for reference in wide engineering application were provided. On the basis of this, the development trend of the active control and generation method of the surface morphology was prospected.

Graphene is an ideal material for energy storage application as its excellent mechanical and physical properties. 3D printed graphene materials will be widely applied in energy storage field for its precisely controllable structure and it is easy to realize large-scale preparation. In this paper, the progress of 3D printed graphene materials synthesis technology and its application in energy storage field were reviewed. The viscosity and printability of graphene ink are key factors for realizing graphene 3D printing. Scalable preparation of graphene ink with facile process, controllable concentration and additive free will be the research focus of graphene 3D printing technologies in the future. The integrated printing of graphene energy storage devices such as graphene supercapacitor, lithium-sulfur battery and lithium ion battery is the development direction in this area.

The current high entropy alloys' studies are most in block, powder, coating, film and other areas. There are few studies of high entropy alloys in other areas and they are lack of unified classification. According to the current high entropy alloys' research situation, The paper has focused on the classification on all kinds of high entropy alloys having been researched, introduced the selecting principle of elements, summarized the preparation methods, reviewed the research institutions, research methods and research contents of high entropy alloys, prospected the application prospect of high entropy alloys, put forward a series of scientific problems of high entropy alloys, including less research on mechanism, incomplete performance research, unsystematic thermal stability study, preparation process parameters to be optimized, lightweight high entropy alloys' design, the expansion on the research field, etc, and the solutions have been given. Those have certain guiding significance for the expansion of the application of high entropy alloys subjects in the future research direction.

Based on years of airworthiness regulations research, combined with the experience of airworthiness certification of civil aviation products, the airworthiness requirement to materials for civil aviation products was analyzed. The key airworthiness requirement for materials is that materials should conform to some material specification to ensure their having the strength and other properties adopted in the design data. The shortcomings of domestic airworthiness management methods for civil aviation materials was discussed and three recommendations for improvement were proposed:(1) conduct individual airworthiness management for civil aviation materials according to CCAR 21.351 through 371 and CCAR 37; (2) develop and promote statistical-based material specification developing methods, to establish material specifications which could ensure material having the strength and other properties adopted in the design data; (3) establish a cooperation mechanism for developing material design value data base for civil aviation materials to reduce the cost of airworthiness certification activities. At the end of this paper, statistical methods used for establishing material specifications were discussed.

SiC whiskers were prepared on the matrix of graphite by using high hydrogenous silicone oil(PSO) as raw material. The effect of surface conditions of graphite and heating temperature on the growth of SiC whisker was mainly studied in this paper. The main factor which affects the nucleation and growth of SiC whisker is the heating temperature, with the heating temperature rising, the production of SiC whisker increases. The surface condition of graphite matrix also influences the growth of SiC whisker. With the nucleation points provided by graphite matrix defects increasing, the production of SiC whisker incleases and SiC whisker starts to overlap with each other. The formation process of SiC whisker includes two steps:nucleation and growth. SiC whisker nucleates at low temperature and grows at high temperature, which follows the VLS (vapor-liquid-solid) growth mechanism.

Surface physicochemical properties of aluminum alloy can be changed by different surface treatment methods, which determines the performance of adhesively bonded joints. This paper reviews the research status on the interfacial bonding strength and corrosion resistance of adhesively bonded aluminum alloys joints from the perspectives of surface roughness, surface micro-structure, surface oxide and coated chemistry properties. Then the problems and development of adhesively bonded aluminum alloys are discussed. The characterization of the aluminum surface physical and chemical properties and the relation model between the surface properties and the adhesive performance are considered to be focused directions for the further research.

Silicon carbide (SiC) ceramics prepared by the conventional process has excellent properties and wide application prospects, but the increased cost of high-temperature preparation process restricts its further development. In contrast, the abundant porous structure of biomass makes itself to be ideal replacement of SiC ceramic prepared at low temperature. This paper reviewed the structure characteristics, preparation methods, pyrolysis mechanism and influence parameters of biomass-based SiC ceramic, and eventually explored the current problems and development trends of the pretreatment of carbon source and silicon source, the pyrolysis process and the application research on the preparation for biomass-based SiC ceramic.

This paper presents the development status and tendency of quantum dot sensitized solar cells. Photoanode research progress and its related technologies are analyzed in detail from the three ways of semiconductor thin films, quantum dot co-sensitization and quantum dot doping, deriving from the approach that the conversion efficiency can be improved by photoanode modification for quantum dot sensitized solar cells. According to the key factors which restrict the cell efficiency, the promising future development of quantum dot sensitized solar cells is proposed,for example,optimizing further the compositions and structures of semiconductor thin films for the photoanodes, exploring new quantum dots with broadband absorption and developing high efficient techniques of interface modification.

The formation process of manufacturing defects in Fiber Reinforced Plastic (FRP) fabricated by automated fiber placement which involves different spatiotemporal scales, the mechanism of defects cannot be achieved by using macroscopic failure theory and experimental analysis methods. To solve these issues, this paper aimed at thermoplastic FRP, the common types of defects and reasons they formed were reported, and the present situation of bubble nucleation, thermo-mechanical coupling, theory of interface strengthening and in-situ consolidation were investigated. More importantly, the shortcomings of the current method for mechanism of defects were pointed out. According to existing multi-scale analysis method and nested relation of material design, multi-scale analysis method of anti-serial nested was presented, furthermore analysis and calculation method of microscopic mechanics parameters were discussed, such as fluidity of matrix, crystallinity, viscoelasticity, hygroscopicity. Finally, multi-scale collaborative design method for process parameters in FRP placement was put forward, based on methods of Grey Relational Analysis (GRA) and Multi-Objective Optimization (MOO). The future research will focus on analysis of the correlation characteristics of processing parameters, manufacturing defects and mechanical properties after application with AFP prototype. The mechanism of defects formation will be then revealed, and simultaneously, processing parameters will be optimized.

This paper focuses on iron-based soft magnetic composites which were synthesized by utilizing the sol-gel method prepared Ni-Zn ferrite particles as insulating compound to coat iron powder, and the influence of NiZnFe2O4 content and molding pressure on the magnetic properties was studied. The morphology, magnetic properties and density of Ni-Zn ferrite insulated compacts were investigated. Scanning electron microscope,line-scan EDX analysis and distribution maps show that the iron particle surface is covered with a thin layer of uniform Ni-Zn ferrites. The existing of the insulating layer can effectively improve the electrical resistivity of soft magnetic composites. Magnetic measurements show that the real part of permeability decreases with the increase of the Ni-Zn ferrite content, and the sample with 3%(mass fraction, the same below) Ni-Zn ferrite has an acceptable real part and minimum imaginary part of permeability in comparison with other samples. Results show that the addition of NiZnFe2O4 can dramatically decrease the internal magnetic loss, the magnetic loss of coated samples decreases by 83.8% as compared with that of uncoated samples at 100kHz. The density of the Fe-3%NiZnFe2O4 compacts reaches 7.14g/cm3 and the saturation magnetization is 1.47T when the molding pressure is 1000MPa.

Graphene oxide nanoribbons (GONRs) nanohybrids were prepared by combining GONRs and other nanoparticles together via the forms of π-π bond or hydrogen bond. This specific combination form can effectively prevent GONRs accumulation, on the other hand, the introduction of new nanoparticles can bring some special properties to the nanohybrids, which is beneficial to give full play to the comprehensive performance of GONRs nanohybrids in polymer modification and other application areas. In this paper, the preparation methods, properties, and application status of GONRs nanohybrids were reviewed in details. Moreover, the structure characteristics, properties, preparation methods and applications of GNRs (as the GONRs reduction product) were also discussed. The related studies have shown that, design and preparation of GONRs nanohybrids is an effective way to the practical application of GONRs, and GNRs as a special two-dimensional variant of graphene, which inherits excellent electrical properties and thermal conductivity from graphene, meanwhile, the special edge effect shows a broader application prospect.

The new requirements of high-frequency magnetic properties are put forward for electronic components with the rapid development of power electronics industry and the use of new electromagnetic materials. The properties of magnetic core, which is the key unit of electronic components, determine the performance of electronic components directly. Therefore, it's necessary to study the high-frequency soft magnetic materials. In this paper, the development history of four types of soft magnetic materials was reviewed. The advantages and disadvantages of each kind of soft magnetic materials and future development trends were pointed out. The emphases were placed on the popular soft magnetic composite materials in recent years. The tendency is to develop high-frequency soft magnetic composite materials with the particle size controllable, uniform coating layer on the core and a mass production method from laboratory to industrialization.

Diamond-like carbon(DLC) films had many unique and outstanding properties such as high thermal conductivity, high hardness, excellent chemical inertness, low friction coefficients and wear coefficients. The properties and combinations were very promising for heat sink, micro-electromechanical devices, radiation hardening, biomedical devices, automotive industry and other technical applications, more research and a lot of attention were attracted in recent years. The research progress of diamond-like films and the nucleation mechanism of film were summarized, and application prospect of DLC films were demonstrated. The aim of this paper is to provide insights on the research trend of DLC films and the industry applications.

As a new type of two-dimensional carbonaceous material, graphene has excellent physical properties and great application potential. The key problem to realize graphene industrialization is to find a large-scale preparing method of graphene with high quality and low cost. In this paper, the advantages and disadvantages of preparation methods for graphene were first reviewed, and then the mechanism, research status and characterization methods of supercritical fluids exfoliated method were introduced in details. And the features of supercritical fluids exfoliated method with the assistance of ultrasonication and pyrene-polymers were summarized. The advantages of supercritical fluids exfoliated method are simple equipment, processing conditions easy to achieve and products with high quality, and a new way of thinking for the industrial production of graphene is provided.

As a typical material of the third-generation semiconductor with wide band gap, high thermal conductivity and high critical breakdown electric field, silicon carbide(SiC) has a huge potential in the applications of photoelectric devices that can work in some extreme conditions, such as in a high temperature or intense radiation environment. Here, the research status of luminescence properties and applications of SiC was summarized. The preparation methods and characteristic luminescence of monocrystal, nanocrystalline and thin film of SiC were presented. Besides, the progress and prospect of SiC luminescence control was also discussed in this paper. Utilizing the emerging technologies, we will be able to modify SiC's properties like luminescence spectrum and efficiency.

The presence of light elements like C, N, O has wide influence on the properties of solar-grade silicon. Since silicon is the dominating raw material of solar cells, the purity of crystalline silicon has significant influence on electrical properties of solar cells. In this paper, the research progress on carbon, nitrogen and oxygen on the presence, distribution, formation mechanism and process control was summarized. An outlook for light elements research in silicon was also proposed, the combination of different purification methods to control and eliminate impurities in silicon is worth paying attention to investigate, and the further research on the behavior of C, N, O in silicon can also improve silicon quality.

Superamphiphobic wear-resistance PPS-based coatings were prepared by a simple spraying method with a pore-forming reagent of NH4HCO3 and nano-filler of carbon nanotubes (CNTs).The surface morphology and the hydrophobicity,oleophobicity of the coating were analyzed by scanning electron microscope (SEM) and contact angle meter.The wear-resistance of the coating was verified by sanding method with given load.The results indicate that a rough surface is obtained after pore-forming,and the porous structures in combination with the CNTs construct the special micro/nano-scale network structures.When the mass fraction of NH4HCO3 is 5%,the contact angles of the coating for water,glycerine and ethylene glycol are 162°,158° and 152°,showing superamphiphobic property.After polished 10000 times by abrasive paper,the coating shows slight friction marks and remains high hydrophobicity,exhibiting excellent wear-resistance.

In the process of thermal spraying remanufacturing,a heterogenerous bonding interface always exists between the coating and matrix due to the materials reason.And the formation and existence of the bonding interface has a significant influence on the coating performance.In this paper,research progress on bonding interface between thermal spraying coating and substrate was summarized,mainly focused on the forming mechanism of bonding interface and its effect on coating performance.The problems on the research of bonding interface between the thermal spraying coating and substrate were analyzed,and aiming at these problems,some suggestions were put forward,such as adopting new technology and approaches to investigate the growing process of the bonding interface in order to reveal its forming mechanism,exploiting new characterization method to realize quantitative characterization of bonding interface morphology and structure so as to build the quantitative relationship between bonding interface and coating properties,and etc. and to lay foundation for the implementation on design and control of the coating properties and life prediction.

Graphene oxide (GO) has wide applications and development prospects in the functional composites owing to its many unique properties, such as two-dimensional structure and large theoretical specific surface areas as well as hydrophilic and polarized interface. The present situation and progress of the graphene oxide composites used in reinforcing and toughening, adsorption separation, photocatalysis and biological medicine were introduced in this paper. The mechanism of producing reinforcing and toughening of polymer and cement based composites caused by forming regular and ordered microstructure regulated with GO nanosheets was mainly summerized. Meanwhile, application principle of the GO composites in the field of adsorption, photocatalysis and biological medicine were analyzed. Finally, the application and development trend of GO composites in reinforcing and toughness as well as adsorption and photocatalysis were pointed out.

Graphene oxide/chitosan is a new type of biocomposites which was developed in recent years, it possesses the unique mechanical, adsorptive, electrochemical and antibacterial properties. The research progress of graphene oxide/chitosan composites was summarized in this paper. The preparation methods of the biocomposites were introduced briefly. Meanwhile, the application of the biocomposites in the field of high mechanical strength of materials, waste water treatment, electrochemical sensor and biomedical materials were illustrated in details. At last, the low cost and large scale preparation, structure and properties of composite materials and its application in new areas of graphene oxide/chitosan biocomposites were prospected.

Research progress of microwave curing on epoxy resin and its composites was summarized on the basis of introducing the principle of microwave curing technology and its advantages. The paper focused on the effect of microwave curing on the curing rate of epoxy resin and its composites as well as the mechanical and thermal properties of cured products. Two suitable composite systems for wave curing of powder-strengthened epoxy and fiber-strengthened epoxy and a few key technological problems for industrial application are introduced. The application prospect of microwave curing on epoxy resin and its composites was also presented.

Some advanced high temperature titanium alloys are usually selected to be manufactured into blade, disc, case, blisk and bling under high temperature environment in compressor and turbine system of a new generation high thrust-mass ratio aero-engine. The latest research progress of 600℃ high temperature titanium alloy, fireproof titanium alloy, TiAl alloy, continuous SiC fiber reinforced titanium matrix composite and their application technology in recent years in China were reviewed in this paper. The key technologies need to be broken through in design, processing and application of new material and component are put forward, including industrial ingot composition of high purified and homogeneous control technology, preparation technology of the large size bar and special forgings, machining technology of blisk and bling parts, material property evaluation and application design technique. The future with the continuous application of advanced high temperature titanium alloys, will be a strong impetus to the development of China's aero-engine technology.

Metamaterials, man-made materials, enable us to design our own "atoms", and thereby to create materials with unprecedented effective properties that have not yet been found in nature. Smart metamaterial is one of those that is an intelligent perceptive to the changes from external environments and simultaneously having the capability to respond to thermal and mechanical stimuli. This paper can provide a review on these smart metamaterials in perspective of science, engineering and industrial products. We divide smart metamaterials according to what they are tuning into: optical, mechanical, thermal and coupled smart metamaterials. The rest of two techniques we addressed are modelling/simulation and fabrication/gene engineering. All of these types smart materials presented here are associated with at least five fundamental research: coupled mechanism of multi-physics fields, man-made design for atom/molecular, metamaterials coupled with natural materials, tunability of metamaterials, and mechanism of sensing metamaterials. Therefore, we give a systematic overview of various potential smart metamaterials together with the upcoming challenges in the intriguing and promising research field.

The microstructure and property degradation of turbine blades in aircraft engines during service would finally pose threat to service safety. But report on systematic research work about microstructure and property degradation of serviced turbine blades is limited. In this paper, the 2nd stage turbine blade made of wrought Ni-based superalloy GH4033 was taken from an aircraft engine and investigated by metallographic analysis and physical and chemical phase analysis after service exposure for about 1600 engine operating hours (EOH). Microstructural features including grain microstructure, γ+γ' matrix and grain boundary (GB) carbides in different locations of the serviced blade were observed and quantitatively characterized. Vickers hardness and stress rupture tests were also conducted. The microstructure characterization indicates that the degradation in grain size, γ' precipitates and GB carbides is rarely observed in the airfoil. The service temperature is estimated to be lower than 700℃ based on the coarsen of γ' phase. The Vickers hardness and rupture lives of different locations in this blade are similar to those in the shank and met the requirement of Chinese Aeronautical Industry Standard HB/Z 91-1985. Therefore, it is suggested that the service exposure of this blade can be continuously prolonged. This study would be helpful for the evaluation of turbine blade made of wrought superalloys containing low volume fraction of γ' precipitates.