This research has investigated the in-situ Ti alloying of aluminum alloys and its application to A356 alloys and wheels through the evaluation of microstructure and mechanical properties. The results showed that stabl...This research has investigated the in-situ Ti alloying of aluminum alloys and its application to A356 alloys and wheels through the evaluation of microstructure and mechanical properties. The results showed that stable titanium content can be obtained by adding a small quantity of TiO2 into electrolyte of pure aluminum. Under this approach, a greater than 95% absorptivity of titanium was achieved, and the microstructure of the specimens was changed to fine equiaxed grains from coarse columnar grains in the pure aluminum. In comparison with the tradition A356 alloys and wheels, the corresponding microstructure in the testing A356 alloys and wheels was finer. Although the tensile strength was similar between the testing and the tradition A356 alloys and wheels, the ductility of the former (testing) is superior to that of the later (tradition), leading to an excellent combination of strength and ductility from the testing alloys and wheels.展开更多
Although dielectric elastomer(DE)with substantial actuated strain(AS)has been reported 20 years ago,its scientific understanding remains unclear.The most accepted theory of DE,which is proposed in 2000,holds the view ...Although dielectric elastomer(DE)with substantial actuated strain(AS)has been reported 20 years ago,its scientific understanding remains unclear.The most accepted theory of DE,which is proposed in 2000,holds the view that AS of DE is induced by the Maxwell stress.According to this theory,materials have similar ratios of permittivity and Young’s modulus should have similar AS,while the experimental results are on contrary to this theory,and the experimental AS has no relationship with ideal AS.Here,a new dipole-conformation-actuated strain cross-scale model is proposed,which can be generally applied to explain the AS of DE without pre-strain.According to this model,several characteristics of an ideal DE are listed in this work and a new DE based on polyphosphazene(PPZ)is synthesized.The AS of PPZ can reach 84%without any pre-strain.At last,a PPZ-based all soft artificial heart(ASAH)is built,which works in the similar way with natural myocardium,indicating that this material has great application potential and possibility in the construction of an ASAH for heart failure(HF)patients.展开更多
文摘This research has investigated the in-situ Ti alloying of aluminum alloys and its application to A356 alloys and wheels through the evaluation of microstructure and mechanical properties. The results showed that stable titanium content can be obtained by adding a small quantity of TiO2 into electrolyte of pure aluminum. Under this approach, a greater than 95% absorptivity of titanium was achieved, and the microstructure of the specimens was changed to fine equiaxed grains from coarse columnar grains in the pure aluminum. In comparison with the tradition A356 alloys and wheels, the corresponding microstructure in the testing A356 alloys and wheels was finer. Although the tensile strength was similar between the testing and the tradition A356 alloys and wheels, the ductility of the former (testing) is superior to that of the later (tradition), leading to an excellent combination of strength and ductility from the testing alloys and wheels.
基金supported by the Basic Science Center Program of the National Natural Science Foundation of China (51988102)the National Key Research and Development Program of China (2017YFB0306903)+2 种基金the Major Program of National Natural Science Foundation of China (51790501)the Innovative Research Groups (51221002 and 51521062)the National Natural Science Foundation of China (52003024)
文摘Although dielectric elastomer(DE)with substantial actuated strain(AS)has been reported 20 years ago,its scientific understanding remains unclear.The most accepted theory of DE,which is proposed in 2000,holds the view that AS of DE is induced by the Maxwell stress.According to this theory,materials have similar ratios of permittivity and Young’s modulus should have similar AS,while the experimental results are on contrary to this theory,and the experimental AS has no relationship with ideal AS.Here,a new dipole-conformation-actuated strain cross-scale model is proposed,which can be generally applied to explain the AS of DE without pre-strain.According to this model,several characteristics of an ideal DE are listed in this work and a new DE based on polyphosphazene(PPZ)is synthesized.The AS of PPZ can reach 84%without any pre-strain.At last,a PPZ-based all soft artificial heart(ASAH)is built,which works in the similar way with natural myocardium,indicating that this material has great application potential and possibility in the construction of an ASAH for heart failure(HF)patients.