The variation of bonding ratio in the press bonding of TC4 alloy at temperatures from 850 to 900℃,pressures from 10 to 30 MPa,and time from 5 to 15 min was investigated.The bonding ratio increases with the increase o...The variation of bonding ratio in the press bonding of TC4 alloy at temperatures from 850 to 900℃,pressures from 10 to 30 MPa,and time from 5 to 15 min was investigated.The bonding ratio increases with the increase of temperature,time and pressure.The maximum bonding ratio,i.e.98 %,can be obtained at 900℃,30 MPa and 15 min.The significance and interaction of bonding parameters with the bonding ratio were investigated.The results demonstrate that the effect of pressure on the bonding ratio is the most effective and the effect of temperature is secondary,while the effect of time is not very powerful.The interaction of bonding parameter on the bonding ratio exists but that is distinguishing in different bonding parameter ranges.It is concluded that increasing pressure can be considered as the primary method to increase the bonding ratio.展开更多
Two-dimensional self-assemblies of four partially fluorinated molecules, 1,4-bis(2,6-difluoropyridin-4-yl)benzene, 4,4'-bis(2,6-difluoropyridin-4-yl)-1,1'-biphenyl, 4,4'-bis(2,6-difluoropyridin-4-yl)-1,1':4...Two-dimensional self-assemblies of four partially fluorinated molecules, 1,4-bis(2,6-difluoropyridin-4-yl)benzene, 4,4'-bis(2,6-difluoropyridin-4-yl)-1,1'-biphenyl, 4,4'-bis(2,6-difluoropyridin-4-yl)-1,1':4',1'-terphenyl and 4,4'-bis(2,6-difluoropyridin-3-yl)-1,1'-biphenyl, involving weak intermolecular C-H···F and C-H···N hydrogen bonds were systematically investigated on Au(111) with low-temperature scanning tunneling microscopy. The inter-molecular connecting modes and binding sites were closely related to the backbones of the building blocks, i.e., the molecule length determines its binding sites with neighboring molecules in the assemblies while the attaching positions of the N and F atoms dictate its approaching and docking angles. The experimental results demonstrate that multiple weak hydrogen bonds such as C-H···F and C-H···N can be efficiently applied to tune the molecular orientations and the self-assembly structures accordingly.展开更多
基金financially supported by the National Natural Science Foundation of China (No.51275416)
文摘The variation of bonding ratio in the press bonding of TC4 alloy at temperatures from 850 to 900℃,pressures from 10 to 30 MPa,and time from 5 to 15 min was investigated.The bonding ratio increases with the increase of temperature,time and pressure.The maximum bonding ratio,i.e.98 %,can be obtained at 900℃,30 MPa and 15 min.The significance and interaction of bonding parameters with the bonding ratio were investigated.The results demonstrate that the effect of pressure on the bonding ratio is the most effective and the effect of temperature is secondary,while the effect of time is not very powerful.The interaction of bonding parameter on the bonding ratio exists but that is distinguishing in different bonding parameter ranges.It is concluded that increasing pressure can be considered as the primary method to increase the bonding ratio.
基金supported by NSFC(Nos.21333001,21133001,21261130090),ChinaNRF CREATE-SPURc project(No.R-143-001-205-592),Singapore
文摘Two-dimensional self-assemblies of four partially fluorinated molecules, 1,4-bis(2,6-difluoropyridin-4-yl)benzene, 4,4'-bis(2,6-difluoropyridin-4-yl)-1,1'-biphenyl, 4,4'-bis(2,6-difluoropyridin-4-yl)-1,1':4',1'-terphenyl and 4,4'-bis(2,6-difluoropyridin-3-yl)-1,1'-biphenyl, involving weak intermolecular C-H···F and C-H···N hydrogen bonds were systematically investigated on Au(111) with low-temperature scanning tunneling microscopy. The inter-molecular connecting modes and binding sites were closely related to the backbones of the building blocks, i.e., the molecule length determines its binding sites with neighboring molecules in the assemblies while the attaching positions of the N and F atoms dictate its approaching and docking angles. The experimental results demonstrate that multiple weak hydrogen bonds such as C-H···F and C-H···N can be efficiently applied to tune the molecular orientations and the self-assembly structures accordingly.