Three types of anodic films(unsealed,hot water sealed and agent sealed)were prepared to study the effects of anodic film structure on the adhesive bonding performance of AA5754 automotive sheets.The morphology of the ...Three types of anodic films(unsealed,hot water sealed and agent sealed)were prepared to study the effects of anodic film structure on the adhesive bonding performance of AA5754 automotive sheets.The morphology of the anodic films was examined by using scanning electron microscope(SEM)and the composition was examined by glow discharge optical emission spectroscopy(GDOES).The adhesive bonding strength and the durability in corrosive environment were investigated by using single lap-hear test and salt spray test(SST),respectively.The results showed that the unsealed sample could provide high initial bonding strength,but the durability was poor in corrosive environment.The hot water sealed sample could provide high durability,but the bonding strength was low.In contrast,the agent sealed sample displayed porous structure at outer layer and partially plugged nano pores structure at inner layer,providing both excellent bonding strength and durability.展开更多
Pure commercial titanium was welded with two types of stainless steel,namely SUS 304 austenitic stainless steel and SUS 821L1 duplex stainless steel.The wavy interface of SUS 821L1 was smaller than that of SUS 304.The...Pure commercial titanium was welded with two types of stainless steel,namely SUS 304 austenitic stainless steel and SUS 821L1 duplex stainless steel.The wavy interface of SUS 821L1 was smaller than that of SUS 304.The vortex zone was observed from both longitudinal and transverse directions,and its composition was analyzed.The interface of Ti/SUS 821L11 was able to bear 401−431 MPa shear load while that of Ti/SUS 304 could withstand 352−387 MPa.The weldability window was used to analyze experimental phenomenon.Furthermore,the smoothed particle hydrodynamics(SPH)numerical simulation method was used to simulate the wavy interface.The trend of wavelength and amplitude change with strength and the stand-offs was consistent with the experimental results.展开更多
Based on the data from typical sites in the Jianghuai region,many kinds of soil layer seismic response are modeled by increasing and decreasing the measured values of shear velocity to a certain scale. The seismic res...Based on the data from typical sites in the Jianghuai region,many kinds of soil layer seismic response are modeled by increasing and decreasing the measured values of shear velocity to a certain scale. The seismic response of soil layer sites are calculated using the one-dimensional equivalent linear method in the frequency domain by choosing the Taft,Kobe and El-centro records as the ground motion input. The results show that the impact of shear velocity variability on the surface ground motion is in relation to the soil layer structure and ground motion input parameters such as amplitude and spectral characteristic. With the increase of shear velocity,the PGA( peak ground acceleration)on the surface of site will increase,however,the characteristic period of the acceleration response spectra is decreasing.展开更多
基金Project(2018MXJH17)supported by the Technology Foundation of Aluminum Corporation of China
文摘Three types of anodic films(unsealed,hot water sealed and agent sealed)were prepared to study the effects of anodic film structure on the adhesive bonding performance of AA5754 automotive sheets.The morphology of the anodic films was examined by using scanning electron microscope(SEM)and the composition was examined by glow discharge optical emission spectroscopy(GDOES).The adhesive bonding strength and the durability in corrosive environment were investigated by using single lap-hear test and salt spray test(SST),respectively.The results showed that the unsealed sample could provide high initial bonding strength,but the durability was poor in corrosive environment.The hot water sealed sample could provide high durability,but the bonding strength was low.In contrast,the agent sealed sample displayed porous structure at outer layer and partially plugged nano pores structure at inner layer,providing both excellent bonding strength and durability.
文摘Pure commercial titanium was welded with two types of stainless steel,namely SUS 304 austenitic stainless steel and SUS 821L1 duplex stainless steel.The wavy interface of SUS 821L1 was smaller than that of SUS 304.The vortex zone was observed from both longitudinal and transverse directions,and its composition was analyzed.The interface of Ti/SUS 821L11 was able to bear 401−431 MPa shear load while that of Ti/SUS 304 could withstand 352−387 MPa.The weldability window was used to analyze experimental phenomenon.Furthermore,the smoothed particle hydrodynamics(SPH)numerical simulation method was used to simulate the wavy interface.The trend of wavelength and amplitude change with strength and the stand-offs was consistent with the experimental results.
基金sponsored by the Anhui Natural Science Foundation Project(10040606Q24)the Youth Seismic Research Program of Anhui Province,China(20120707)and(20140301)
文摘Based on the data from typical sites in the Jianghuai region,many kinds of soil layer seismic response are modeled by increasing and decreasing the measured values of shear velocity to a certain scale. The seismic response of soil layer sites are calculated using the one-dimensional equivalent linear method in the frequency domain by choosing the Taft,Kobe and El-centro records as the ground motion input. The results show that the impact of shear velocity variability on the surface ground motion is in relation to the soil layer structure and ground motion input parameters such as amplitude and spectral characteristic. With the increase of shear velocity,the PGA( peak ground acceleration)on the surface of site will increase,however,the characteristic period of the acceleration response spectra is decreasing.
