The micro-alloying effects of Y on the microstructure, mechanical properties, and bio-corrosion behavior of Mg69-xZn27Ca4Yx（x= 0, 1, 2 at.%） alloys were investigated through X-ray diffraction, compressive tests,elec...The micro-alloying effects of Y on the microstructure, mechanical properties, and bio-corrosion behavior of Mg69-xZn27Ca4Yx（x= 0, 1, 2 at.%） alloys were investigated through X-ray diffraction, compressive tests,electrochemical treatments, and immersion tests. The Mg69Zn27Ca4 alloy was found to be absolutely amorphous, and its glass-forming ability decreased with the addition of Y. The Mg68Zn27Ca4Y1 alloy exhibited an ultrahigh compressive strength above 1010 MPa as well as high capacity for plastic strain above 3.1%.Electrochemical and immersion tests revealed that these Y-doped MgeZ neC a alloys had good bio-corrosion resistance in simulated body fluid（SBF） at 37℃. The results of the cytotoxicity test showed high cell viabilities for these alloys, which means good bio-compatibility.展开更多
Ti47Cu38-xZr7.5Fe2.5Sn2 Si1 Ag2 Tax(x=1-4;at%,the same below)bulk metallic glasses(BMGs)with good bio-corrosion resistance and mechanical properties were fabricated by copper mold casting.Critical diameter of the Ti-b...Ti47Cu38-xZr7.5Fe2.5Sn2 Si1 Ag2 Tax(x=1-4;at%,the same below)bulk metallic glasses(BMGs)with good bio-corrosion resistance and mechanical properties were fabricated by copper mold casting.Critical diameter of the Ti-based BMGs with 1 at%-4 at%Ta was 3 mm.The Ta-incorporated Ti-based BMGs exhibit higher open current potential and parallel passive current density in comparison with those of Ti-6 Al-4 V alloy in 0.9 wt%NaCl and Hank’s solution,implying their good corrosion resistance.The pitting corrosion potential of the Ti-based BMGs gradually increases up to about 1.25 V with Ta addition increasing up to 4 at%in 0.9 wt%NaCl solution.Among the present Ti-based BMGs,the alloy bearing2 at%Ta exhibits the optimal integration of mechanical properties,including the compressive fracture strength exceeding 2000 MPa,relative low Young’s modulus of98 GPa,plastic strain of 3.4%and high hardness of HV599.The Ta-bearing Ti-based bulk metallic glasses with integration of relative high GFA,good mechanical properties and high bio-corrosion resistance are beneficial for biomedical applications.展开更多
Mg?1Zn?0.5Ca alloys were prepared by traditional steel mould casting and water-cooled copper mould injection casting at higher cooling rate. Microstructure, mechanical properties and bio-corrosion resistance of two al...Mg?1Zn?0.5Ca alloys were prepared by traditional steel mould casting and water-cooled copper mould injection casting at higher cooling rate. Microstructure, mechanical properties and bio-corrosion resistance of two alloys were contrastively investigated. Grain size reduces remarkably and microstructure becomes homogenous when raising cooling rate. The bio-corrosion behaviour in 3.5% sodium chloride solution (3.5% NaCl) and Hank’s solution at 37°C was investigated using electrochemical polarization measurement and the results indicate that the alloy prepared at higher cooling rates has better corrosion resistance in both types of solution. Further mass loss immersion test in Hank’s solution reveals the same result. The reason of corrosion resistance improvement is that raising cooling rate brings about homogeneous microstructure, which leads to micro-galvanic corrosion alleviation. The tensile test results show that yield strength, ultimate tensile strength and elongation are improved by raising cooling rate and the improvement is mainly due to grain refinement.展开更多
基金support of the National Natural Science Foundation of China (No. 51271206), Chinathe National Basic Research Program of China (No. 2013 CB632201), Chinathe Program for New Century Excellent Talents in University (No. NCET-11-0554), China
文摘The micro-alloying effects of Y on the microstructure, mechanical properties, and bio-corrosion behavior of Mg69-xZn27Ca4Yx（x= 0, 1, 2 at.%） alloys were investigated through X-ray diffraction, compressive tests,electrochemical treatments, and immersion tests. The Mg69Zn27Ca4 alloy was found to be absolutely amorphous, and its glass-forming ability decreased with the addition of Y. The Mg68Zn27Ca4Y1 alloy exhibited an ultrahigh compressive strength above 1010 MPa as well as high capacity for plastic strain above 3.1%.Electrochemical and immersion tests revealed that these Y-doped MgeZ neC a alloys had good bio-corrosion resistance in simulated body fluid（SBF） at 37℃. The results of the cytotoxicity test showed high cell viabilities for these alloys, which means good bio-compatibility.
基金financially supported by the National Natural Science Foundation of China(Nos.51671008 and 51701008)the Aeronautical Science Foundation of China(No.2013ZE51060)China Postdoctoral Science Foundation(No.2017M620575)。
文摘Ti47Cu38-xZr7.5Fe2.5Sn2 Si1 Ag2 Tax(x=1-4;at%,the same below)bulk metallic glasses(BMGs)with good bio-corrosion resistance and mechanical properties were fabricated by copper mold casting.Critical diameter of the Ti-based BMGs with 1 at%-4 at%Ta was 3 mm.The Ta-incorporated Ti-based BMGs exhibit higher open current potential and parallel passive current density in comparison with those of Ti-6 Al-4 V alloy in 0.9 wt%NaCl and Hank’s solution,implying their good corrosion resistance.The pitting corrosion potential of the Ti-based BMGs gradually increases up to about 1.25 V with Ta addition increasing up to 4 at%in 0.9 wt%NaCl solution.Among the present Ti-based BMGs,the alloy bearing2 at%Ta exhibits the optimal integration of mechanical properties,including the compressive fracture strength exceeding 2000 MPa,relative low Young’s modulus of98 GPa,plastic strain of 3.4%and high hardness of HV599.The Ta-bearing Ti-based bulk metallic glasses with integration of relative high GFA,good mechanical properties and high bio-corrosion resistance are beneficial for biomedical applications.
基金Project(20921002)supported by the Innovative Research Groups of the National Natural Science Foundation of ChinaProject(21221061)supported by the National Natural Science Foundation of China+1 种基金Project(201105007)supported by the Science and Technology Program of Jilin Province,ChinaProject(20140325003GX)supported by the Science and Technology Support Project of Jilin Province,China
文摘Mg?1Zn?0.5Ca alloys were prepared by traditional steel mould casting and water-cooled copper mould injection casting at higher cooling rate. Microstructure, mechanical properties and bio-corrosion resistance of two alloys were contrastively investigated. Grain size reduces remarkably and microstructure becomes homogenous when raising cooling rate. The bio-corrosion behaviour in 3.5% sodium chloride solution (3.5% NaCl) and Hank’s solution at 37°C was investigated using electrochemical polarization measurement and the results indicate that the alloy prepared at higher cooling rates has better corrosion resistance in both types of solution. Further mass loss immersion test in Hank’s solution reveals the same result. The reason of corrosion resistance improvement is that raising cooling rate brings about homogeneous microstructure, which leads to micro-galvanic corrosion alleviation. The tensile test results show that yield strength, ultimate tensile strength and elongation are improved by raising cooling rate and the improvement is mainly due to grain refinement.
