The key parameters of the adhesive layer of a reinforcing patch are of great significance and affect the ability to suppress crack propagation in an Al–Li alloy patch-reinforced structure.This paper proposes a method...The key parameters of the adhesive layer of a reinforcing patch are of great significance and affect the ability to suppress crack propagation in an Al–Li alloy patch-reinforced structure.This paper proposes a method to determine the key parameters of the adhesive layer of adhesively bonded joints in the Al–Li alloy patch-reinforced structure.A zero-thickness cohesive zone model(CZM)was selected to simulate the adhesive layer’s fracture process,and an orthogonal simulation was designed to compare against the test results.A three-dimensional progressive damage model of an Al–Li alloy patch-reinforced structure with single-lap adhesively bonded joints was developed.The simulation’s results closely agree with the test results,demonstrating that this method of determining the key parameters is likely accurate.The results also verify the correctness of the cohesive strength and fracture energy,the two key parameters of the cohesive zone model.The model can accurately predict the strength and fracture process of adhesively bonded joints,and can be used in research to suppress crack propagation in Al–Li alloy patch-reinforced structures.展开更多
To study the combustion performance of aluminum-based micro-cell composite fuel aluminum@ammonium perchlorate(Al@AP),in hydroxyl-terminated polybutadiene(HTPB)solid propellant,the Al@AP was added to HTPB solid propell...To study the combustion performance of aluminum-based micro-cell composite fuel aluminum@ammonium perchlorate(Al@AP),in hydroxyl-terminated polybutadiene(HTPB)solid propellant,the Al@AP was added to HTPB solid propellant instead of Al powder and part of AP.Firstly,the ignition and energy performance of Al@AP were investigated and the effects of Al@AP on the combustion,process and mechanical properties of HTPB solid propellant were studied by means of sphere explosion test system,adiabatic oxygen bomb calorimeter test,standard test engine test,residual active Al test,viscosity test,and tensile test.In addition,the combustion mechanism of Al@AP in HTPB solid propellant was analyzed.The results indicate that Al@AP composites offer faster ignition response than simple physical blends,and the heat of HTPB solid propellant increases from 7385 J·g^(-1) to 7834 J·g^(-1) when 21.3%Al@AP was used instead of aluminium powder.The amount of residue decreases from 3.88%to 2.10%in mass fraction,the content of active Al in residue decrease from 6.14%to 2.57%,and the particle size d_(50) of residue decrease from 298μm to 62μm.The combustion efficiency of HTPB solid propellant improves from 94.0%to 94.6%.The mechanical and process properties of HTPB propellant containing Al@AP can satisfy the application.展开更多
The samples consisting of 100nm Al or Ag film on optical glass substrate were irradiated by a beam of Xe 5×10<sup>15</sup> to 2×10<sup>16</sup> cm<sup>-2</sup> with energy...The samples consisting of 100nm Al or Ag film on optical glass substrate were irradiated by a beam of Xe 5×10<sup>15</sup> to 2×10<sup>16</sup> cm<sup>-2</sup> with energy 320 keV. The adhesion of films on substrates was tested by Xe<sup>+</sup> irradiation. Optical character was measured by spectrophotometer. The ion mixing amount was measured by RBS. The results showed that after ion irradiating the adhesion of the film on the glass is enhanced. The adherent strength is greater than 10 kg/cm<sup>2</sup>. The thermal stability of the films is good. The irradiated film is more optically efficient, the surface is smooth and rendered more corrosion resistance. The mechanism of the film adhesion was discussed.展开更多
基金Project(51575535)supported by the National Natural Science Foundation of ChinaProject(2015CX002)supported by the Innovation-driven Plan in Central South University,China+2 种基金Project(zzyjkt2013-09B)supported by the Fund of the State Key Laboratory of High Performance Manufacturing,ChinaProject(2017zzts638)supported by the Fundamental Research Funds for the Central Universities,ChinaProject(2016RS2015)supported by the Scientific and Technological Leading Talent Projects of Hunan Province,China
文摘The key parameters of the adhesive layer of a reinforcing patch are of great significance and affect the ability to suppress crack propagation in an Al–Li alloy patch-reinforced structure.This paper proposes a method to determine the key parameters of the adhesive layer of adhesively bonded joints in the Al–Li alloy patch-reinforced structure.A zero-thickness cohesive zone model(CZM)was selected to simulate the adhesive layer’s fracture process,and an orthogonal simulation was designed to compare against the test results.A three-dimensional progressive damage model of an Al–Li alloy patch-reinforced structure with single-lap adhesively bonded joints was developed.The simulation’s results closely agree with the test results,demonstrating that this method of determining the key parameters is likely accurate.The results also verify the correctness of the cohesive strength and fracture energy,the two key parameters of the cohesive zone model.The model can accurately predict the strength and fracture process of adhesively bonded joints,and can be used in research to suppress crack propagation in Al–Li alloy patch-reinforced structures.
文摘To study the combustion performance of aluminum-based micro-cell composite fuel aluminum@ammonium perchlorate(Al@AP),in hydroxyl-terminated polybutadiene(HTPB)solid propellant,the Al@AP was added to HTPB solid propellant instead of Al powder and part of AP.Firstly,the ignition and energy performance of Al@AP were investigated and the effects of Al@AP on the combustion,process and mechanical properties of HTPB solid propellant were studied by means of sphere explosion test system,adiabatic oxygen bomb calorimeter test,standard test engine test,residual active Al test,viscosity test,and tensile test.In addition,the combustion mechanism of Al@AP in HTPB solid propellant was analyzed.The results indicate that Al@AP composites offer faster ignition response than simple physical blends,and the heat of HTPB solid propellant increases from 7385 J·g^(-1) to 7834 J·g^(-1) when 21.3%Al@AP was used instead of aluminium powder.The amount of residue decreases from 3.88%to 2.10%in mass fraction,the content of active Al in residue decrease from 6.14%to 2.57%,and the particle size d_(50) of residue decrease from 298μm to 62μm.The combustion efficiency of HTPB solid propellant improves from 94.0%to 94.6%.The mechanical and process properties of HTPB propellant containing Al@AP can satisfy the application.
文摘The samples consisting of 100nm Al or Ag film on optical glass substrate were irradiated by a beam of Xe 5×10<sup>15</sup> to 2×10<sup>16</sup> cm<sup>-2</sup> with energy 320 keV. The adhesion of films on substrates was tested by Xe<sup>+</sup> irradiation. Optical character was measured by spectrophotometer. The ion mixing amount was measured by RBS. The results showed that after ion irradiating the adhesion of the film on the glass is enhanced. The adherent strength is greater than 10 kg/cm<sup>2</sup>. The thermal stability of the films is good. The irradiated film is more optically efficient, the surface is smooth and rendered more corrosion resistance. The mechanism of the film adhesion was discussed.
