The Flame-Retardant Mechanisms and Preparation of Polymer Composites and Their Potential Application in Construction Engineering

Against the background of people’s increasing awareness of personal safety and property safety, the flame retardancy (FR) of materials has increasingly become the focus of attention in the field of construction engineering. A variety of materials have been developed in research and production in this field. Polymers have many advantages, such as their light weight, low water absorption, high flexibility, good chemical corrosion resistance, high specific strength, high specific modulus and low thermal conductivity, and are often applied to the field of construction engineering. However, the FR of unmodified polymer is not ideal, and new methods to make it more flame retardant are needed to enhance the FR. This article primarily introduces the flame-retardant mechanism of fire retardancy. It summarizes the preparation of polymer flame-retardant materials by adding different flame-retardant agents, and the application and research progress related to polymer flame-retardant materials in construction engineering.

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Research Progress of the Surface Oxidation of Titanium and its Alloys

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.748.188 ◽

2013 ◽

Vol 748 ◽

pp. 188-191

Author(s):

Hui Jun Yu

Keyword(s):

Titanium Alloys ◽

Biomedical Applications ◽

Influence Factors ◽

Surface Oxidation ◽

Research Progress ◽

Corrosion Resistant ◽

Specific Strength ◽

Existing Problems ◽

High Specific Strength ◽

Micro Arc Oxidation

Titanium and titanium alloys possess some attractive properties, such as excellent corrosion and erosion resistance, low densities, high specific strength and modulus, enabling them extensively used in aeronautical, marine, chemical and biomedical applications and so on. Nevertheless, Recent years, the corrosion resistance of titanium and titanium alloys is required to elevate in some fields, proper surface modification such as surface oxidation can solve the problems effectively. In this paper, the recent investigations of thermal oxidation and micro-arc oxidation to improve the corrosion resistant of titanium and its alloys are reviewed. The structures, properties and their influence factors of the coatings are analysed systematically. And the existing problems and the future prospect of the further researches is mentioned.

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Precipitation in Al-Li-Cu Alloys

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100096941 ◽

1981 ◽

Vol 39 ◽

pp. 44-45

Author(s):

J. E. O'Neal ◽

K. K. Sankaran

Keyword(s):

Electron Microscopy ◽

Age Hardening ◽

Precipitation Behavior ◽

Zone Formation ◽

Specific Strength ◽

Hardening Behavior ◽

Cu Alloys ◽

High Specific Strength ◽

Transmission Electron ◽

Structural Applications

Al-Li-Cu alloys combine high specific strength and high specific modulus and are potential candidates for aircraft structural applications. As part of an effort to optimize Al-Li-Cu alloys for specific applications, precipitation in these alloys was studied for a range of compositions, and the mechanical behavior was correlated with the microstructures.Alloys with nominal compositions of Al-4Cu-2Li-0.2Zr, Al-2.5Cu-2.5Li-0.2Zr, and Al-l.5Cu-2.5Li-0.5Mn were argon-atomized into powder at solidification rates ≈ 103°C/s. Powders were consolidated into bar stock by vacuum pressing and extruding at 400°C. Alloy specimens were solution annealed at 530°C and aged at temperatures up to 250°C, and the resultant precipitation was studied by transmission electron microscopy (TEM).The low-temperature (≲100°C) precipitation behavior of the Al-4Cu-2Li-0.2Zr alloy is a combination of the separate precipitation behaviors of Al-Cu and Al-Li alloys. The age-hardening behavior at these temperatures is characteristic of Guinier-Preston (GP) zone formation, with additional strengthening resulting from the coherent precipitation of δ’ (Al3Li, Ll2 structure), the presence of which is revealed by the selected-area diffraction pattern (SADP) shown in Figure la.

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Development of High-Specific-Strength Envelope Materials

AIAA's 3rd Annual Aviation Technology, Integration, and Operations (ATIO) Forum ◽

10.2514/6.2003-6765 ◽

2003 ◽

Cited By ~ 9

Author(s):

Keiji Komatsu ◽

M. Sano ◽

Y. Kakuta

Keyword(s):

Specific Strength ◽

High Specific Strength

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Microstructural Evolution in Al-Ti Multilayered Film with Annealing

Microscopy and Microanalysis ◽

10.1017/s1431927600017505 ◽

1999 ◽

Vol 5 (S2) ◽

pp. 836-837

Author(s):

R. Mitra ◽

W.A. Chiou ◽

A.Madan ◽

R. Hoffman ◽

J.R. Weertman

Keyword(s):

Magnetron Sputtering ◽

Ingot Metallurgy ◽

Multilayered Film ◽

Multilayered Structures ◽

Multilayered Films ◽

Specific Strength ◽

The Past ◽

High Specific Strength ◽

Significant Interest ◽

Deposited Film

There has been a significant interest in the development of dispersion-hardened aluminum for many years for high specific strength and modulus. Such materials are usually processed by powder or ingot metallurgy routes. In this study, Al3 Ti dispersion hardened Al was obtained by annealing Al-Ti multilayers. Al-Ti multilayered films have been characterized in the past by observing the structure of the layers, as well as tensile properties and hardness. This paper reports the structure of Al-Ti multilayers and the evolution of matrix and dispersoid microstructure on annealing.The Al-Ti multilayered structures were prepared by magnetron sputtering using Al and Ti as targets and either Si (100) or NaCl as substrates. The bi-layer thickness was maintained around 16 nm with Ti constituting 12% of the total. The substrate was alternately moved below the Al and Ti targets for the purpose of deposition. The as-deposited film on the substrate and NaCl salts were annealed at 400°C for periods between 1 and 24 h in a vacuum (10−5 torr) furnace.

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Transient dynamic analysis of the high-specific-strength steel jacket with extreme wave and vessel impact load

Acta Scientiarum Technology ◽

10.4025/actascitechnol.v40i1.36633 ◽

2018 ◽

Vol 40 (1) ◽

pp. 36633

Author(s):

Aidin Kazemi Daliri ◽

Sepanta Naimi

Keyword(s):

Dynamic Analysis ◽

Impact Load ◽

Extreme Wave ◽

Transient Dynamic Analysis ◽

Transient Dynamic ◽

Specific Strength ◽

Steel Jacket ◽

High Specific Strength ◽

Vessel Impact

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Influence of the Flux Ratio N2/Ar on the Formation of Mo-N Modification Layers on Ti6Al4V by Plasma Reactive Sputtering

Materials Science Forum ◽

10.4028/www.scientific.net/msf.610-613.1128 ◽

2009 ◽

Vol 610-613 ◽

pp. 1128-1131

Author(s):

Xiu Yan Li ◽

Ying Zhang ◽

Bin Tang ◽

Zhong Xu

Keyword(s):

Substrate Surface ◽

Surface Hardness ◽

Flux Ratio ◽

Reactive Sputtering ◽

Load Bearing Capacity ◽

Specific Strength ◽

The Poor ◽

High Specific Strength ◽

Composition Structure ◽

Oriented Parallel

Ti6Al4V alloy is promising biology material with outstanding properties of low density, high specific strength, and exceptional corrosion resistance. However, one of its disadvantages is the poor tribological property. In this paper Mo-N hard surface modification layers were formed on Ti6Al4V at 900°C substrate temperature by plasma reactive sputtering. The flux ratio N2/Ar is an important parameter and its influence on the composition, structure and hardness of the Mo-N layers is studied. The Mo-N layers are duplex layers, composed of diffusing layer and surface coating. The component of Mo and N elements in the diffusing layer changes gradually which can enhance the load-bearing capacity to the coating and ensure the durability of the coating. With the increase of the flux ratio N2/Ar, the content of N element in the Mo-N layers increases. The Mo-N layers were polycrystalline γ- Mo2N with (200) plane oriented parallel to the substrate surface. The surface hardness of the formed layers is in the range HK1330-1430. The hardness of the Mo-N layers increases with the increase of the flux ratio N2/Ar and the reason is that the content of N element in the Mo-N layers increases.

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Strengthening Evaluation in a Composite Mg-RE Alloy Using TEM

Materials Science Forum ◽

10.4028/www.scientific.net/msf.678.75 ◽

2011 ◽

Vol 678 ◽

pp. 75-84 ◽

Cited By ~ 2

Author(s):

Marcello Cabibbo

Keyword(s):

Electron Microscopy ◽

Metal Matrix ◽

Room Temperature ◽

Strengthening Mechanism ◽

Composite Alloy ◽

Specific Strength ◽

High Specific Strength ◽

Transmission Electron ◽

Sic Ceramic

Magnesium alloys containing rare earth elements are known to have high specific strength and corrosion resistance. The addition of SiC ceramic particles makes the metal matrix composite stronger with better wear and creep resistance and a still good machinability. The role of the reinforcement particles to the enhanced strength can be quantitatively evaluated using transmission electron microscopy (TEM). This paper presents a quantitative strengthening evaluation in a SiC Mg-RE composite alloy. The different contributions were determined by TEM inspections. The microstructure strengthening mechanism was studied after room temperature compression specimens. The way of combining the different contributions and the comparison to the measured yield stress, is also discussed and justified.

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High Specific Strength Carbon Foam Prepared from Sucrose and Multi-Walled Carbon Nanotube

Materials Science Forum ◽

10.4028/www.scientific.net/msf.830-831.545 ◽

2015 ◽

Vol 830-831 ◽

pp. 545-548

Author(s):

Rajaram Narasimman ◽

Sujith Vijayan ◽

Kuttan Prabhakaran

Keyword(s):

Compressive Strength ◽

Carbon Nanotube ◽

Cellular Structure ◽

Carbon Foam ◽

Specific Strength ◽

High Specific Strength ◽

Multi Walled Carbon Nanotube ◽

Uniform Dispersion ◽

Carbon Foams ◽

Maximum Compressive Strength

Multi-walled carbon nanotube (MWNT) reinforced carbon foams were prepared by thermo-foaming of MWNT dispersions in molten sucrose followed by dehydration and carbonization. The rheological studies showed that the uniform dispersion of MWNT was achieved up to 1.5 wt.%. The carbon foams showed cellular structure. The density of the carbon foams increased with an increase in the MWNT concentration up to 0.25 wt.% and then remained more or less constant. The maximum compressive strength of 4.9 MPa was achieved at the MWNT concentration of 0.5 wt.%.

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