<div style="text-align:justify;"> The constitutive behaviors of the sintered reactive material PTFE/Al/Si, one new formulation proposed by the author, were studied systematically and found it appears s...<div style="text-align:justify;"> The constitutive behaviors of the sintered reactive material PTFE/Al/Si, one new formulation proposed by the author, were studied systematically and found it appears strain-harden, stain-rate harden and temperature-soften effects, so it is more appropriate to describe the mechanical behavior with the Johnson-Cook model. With the static and dynamic experimental results and using the nonlinear fitting method, the mechanical and physical parameters in the Johnson-Cook model were determined, which supply one basis for the future numerical simulation study. </div>展开更多
To improve the wettability of hypereutectic Al−60Si alloy and enhance the mechanical properties of the joints,Al−60Si alloy was joined by ultrasonic soldering with Sn-9Zn solder,and a sound joint with in-situ Si parti...To improve the wettability of hypereutectic Al−60Si alloy and enhance the mechanical properties of the joints,Al−60Si alloy was joined by ultrasonic soldering with Sn-9Zn solder,and a sound joint with in-situ Si particle reinforcement was obtained.The oxide film of Al−60Si alloy at the interface was identified by transmission electron microscopy(TEM)analysis as amorphous Al_(2)O_(3).The oxide of Si particles in the base metal was also alumina.The oxide film of Al−60Si alloy was observed to be removed by ultrasonic vibration instead of holding treatment.Si particle-reinforced joints(35.7 vol.%)were obtained by increasing the ultrasonication time.The maximum shear strength peaked at 99.5 MPa for soldering at 330℃with an ultrasonic vibration time of 50 s.A model of forming of Si particles reinforced joint under the ultrasound was proposed,and ultrasonic vibration was considered to promote the dissolution of Al and migration of Si particles.展开更多
文摘<div style="text-align:justify;"> The constitutive behaviors of the sintered reactive material PTFE/Al/Si, one new formulation proposed by the author, were studied systematically and found it appears strain-harden, stain-rate harden and temperature-soften effects, so it is more appropriate to describe the mechanical behavior with the Johnson-Cook model. With the static and dynamic experimental results and using the nonlinear fitting method, the mechanical and physical parameters in the Johnson-Cook model were determined, which supply one basis for the future numerical simulation study. </div>
基金financial support from the National Natural Science Foundation of China(Nos.52275385,U2167216)Sichuan Province Science and Technology Support Program,China(No.2022YFG0086).
文摘To improve the wettability of hypereutectic Al−60Si alloy and enhance the mechanical properties of the joints,Al−60Si alloy was joined by ultrasonic soldering with Sn-9Zn solder,and a sound joint with in-situ Si particle reinforcement was obtained.The oxide film of Al−60Si alloy at the interface was identified by transmission electron microscopy(TEM)analysis as amorphous Al_(2)O_(3).The oxide of Si particles in the base metal was also alumina.The oxide film of Al−60Si alloy was observed to be removed by ultrasonic vibration instead of holding treatment.Si particle-reinforced joints(35.7 vol.%)were obtained by increasing the ultrasonication time.The maximum shear strength peaked at 99.5 MPa for soldering at 330℃with an ultrasonic vibration time of 50 s.A model of forming of Si particles reinforced joint under the ultrasound was proposed,and ultrasonic vibration was considered to promote the dissolution of Al and migration of Si particles.
基金financially supported by the National Key Research and Development Program of China (No. 2020YFA0405903)the National Natural Science Foundation of China (Nos. 52001159, 52101141)+1 种基金the Natural Science Foundation of Jiangsu ProvinceChina (No. BK20202010)。
基金financially supported by the Fundamental Research Funds for the Central Universities,China(No.2020CDJDPT001)the Chongqing Natural Science Foundation,China(No.cstc2021jcyj-msxm X0699)。
基金supported by the National Natural Science Foundation,China (No.52074131)the National Key R&D Project,China (No.2022YFC3900500)+2 种基金the International Technology Cooperation Program of Guangdong Academy of Sciences,China (No.2020GDASYL-20200504001)the Open Competition to Select the Best Candidate of Shangrao,China (No.2021A005)the BL13HB beamline of Shanghai Synchrotron Radiation Facility (SSRF)for providing synchrotron radiation beamtime (Nos.2020-SSRF-PT-011937,2021-SSRF-PT-017645).
