Face centred cubic（FCC） TiB ceramic powder synthesized by Ti-boronizing method was used as conductive filler to make ceramic electrically conductive adhesives（ECAs） with the polymer matrix.Electrically conductive ...Face centred cubic（FCC） TiB ceramic powder synthesized by Ti-boronizing method was used as conductive filler to make ceramic electrically conductive adhesives（ECAs） with the polymer matrix.Electrically conductive properties of the ceramic ECAs were studied.The bulk electrical resistivity varied with the powder content of the FCC-TiB in ECAs.The FCC-TiB filled ECAs also showed the percolation behavior that usually occurred for the metal-filled ECAs,the percolation threshold was located at the content of 60%FCC-TiB.A minimum value of 0.1 Ω·cm was obtained at a content of 75%FCC-TiB.In order to check the reliability of mechanical property,tensile test was done to measure the shear strength,and the shear strength dropped with increasing the content of FCC-TiB powders.It is about 12.26 MPa at the content of 70%TiB powders.The Cu filled ECAs were also prepared for comparison.The properties of the oxidation resistance of the two ECAs were evaluated.The results show that the ceramic ECAs have excellent oxidation resistance and better stability compared with the Cu filled ECAs.展开更多
The aging behavior of polyurethane adhesive in medium was investigated and compared by means of scanning electronic microscopy（SEM）, infrared spectroscopy（IR）, interface analysis and shearing strength test. The ex...The aging behavior of polyurethane adhesive in medium was investigated and compared by means of scanning electronic microscopy（SEM）, infrared spectroscopy（IR）, interface analysis and shearing strength test. The experimental results show that the shear strength of polyurethane adhesive in salt water is decreased more quickly than that in water. Na^＋ and Cl^- ions could make the polyurethane adhesive age faster and the interface metal corrosion. The high temperature accelerates the diffusion of water molecule, Na^＋ and Cl^- ions and the degradation of the giant molecule.展开更多
resistance,and adhesive strength of vacuum-arc multi-period NbN/Cu coatings is studied.It was found that in thin layers(about 8 nm,in a constant rotation mode),regardless of the change in the pressure of the nitrogen ...resistance,and adhesive strength of vacuum-arc multi-period NbN/Cu coatings is studied.It was found that in thin layers(about 8 nm,in a constant rotation mode),regardless of the change in the pressure of the nitrogen atmosphere,a metastableδ-NbN phase forms(cubic crystal lattice of the NaCl type).At a layer thickness of^40 nm or more,a phase composition changes from the metastableδ-NbN to the equilibriumε-NbN phase with a hexagonal crystal lattice.In the presence of theε-NbN phase in the niobium nitride layers,the highest adhesive strength is achieved with a value of LС5=96.5 N.Corrosion resistance tests have shown that for all the studied samples the corrosion process has mainly an anodic reaction.The highest corrosion resistance was shown by coatings obtained at a pressure of 7·10-4 Torr,with the smallest bias potential of-50 V and the smallest layer thickness;with a thickness of such a coating of about 10 microns,its service life in the environment of the formation of chloride ions is about a year.展开更多
基金Project (51172088) supported by the National Natural Science Foundation of China
文摘Face centred cubic（FCC） TiB ceramic powder synthesized by Ti-boronizing method was used as conductive filler to make ceramic electrically conductive adhesives（ECAs） with the polymer matrix.Electrically conductive properties of the ceramic ECAs were studied.The bulk electrical resistivity varied with the powder content of the FCC-TiB in ECAs.The FCC-TiB filled ECAs also showed the percolation behavior that usually occurred for the metal-filled ECAs,the percolation threshold was located at the content of 60%FCC-TiB.A minimum value of 0.1 Ω·cm was obtained at a content of 75%FCC-TiB.In order to check the reliability of mechanical property,tensile test was done to measure the shear strength,and the shear strength dropped with increasing the content of FCC-TiB powders.It is about 12.26 MPa at the content of 70%TiB powders.The Cu filled ECAs were also prepared for comparison.The properties of the oxidation resistance of the two ECAs were evaluated.The results show that the ceramic ECAs have excellent oxidation resistance and better stability compared with the Cu filled ECAs.
文摘The aging behavior of polyurethane adhesive in medium was investigated and compared by means of scanning electronic microscopy（SEM）, infrared spectroscopy（IR）, interface analysis and shearing strength test. The experimental results show that the shear strength of polyurethane adhesive in salt water is decreased more quickly than that in water. Na^＋ and Cl^- ions could make the polyurethane adhesive age faster and the interface metal corrosion. The high temperature accelerates the diffusion of water molecule, Na^＋ and Cl^- ions and the degradation of the giant molecule.
文摘resistance,and adhesive strength of vacuum-arc multi-period NbN/Cu coatings is studied.It was found that in thin layers(about 8 nm,in a constant rotation mode),regardless of the change in the pressure of the nitrogen atmosphere,a metastableδ-NbN phase forms(cubic crystal lattice of the NaCl type).At a layer thickness of^40 nm or more,a phase composition changes from the metastableδ-NbN to the equilibriumε-NbN phase with a hexagonal crystal lattice.In the presence of theε-NbN phase in the niobium nitride layers,the highest adhesive strength is achieved with a value of LС5=96.5 N.Corrosion resistance tests have shown that for all the studied samples the corrosion process has mainly an anodic reaction.The highest corrosion resistance was shown by coatings obtained at a pressure of 7·10-4 Torr,with the smallest bias potential of-50 V and the smallest layer thickness;with a thickness of such a coating of about 10 microns,its service life in the environment of the formation of chloride ions is about a year.
