In this paper, high-zirconium Zr66＋2xAl9-x（Ni1/3Cu2/3）25-x （x=0,1,2 at.%） bulk metallic glasses with high strength and large duc- tility were fabricated by copper mould casting. The effects of zirconium content o...In this paper, high-zirconium Zr66＋2xAl9-x（Ni1/3Cu2/3）25-x （x=0,1,2 at.%） bulk metallic glasses with high strength and large duc- tility were fabricated by copper mould casting. The effects of zirconium content on the glass-forming ability （GFA）, thermal properties and mechanical properties were investigated using X-ray diffractometer （XRD）, differential scanning calorimeter （DSC）, and mechanical testing system in compressive and three-point bending modes, respectively. The high-zirconium BMGs show the critical diameters of 3-5 ram, the supercooled liquid region ranging from 70 K to 99 K, and the yield strength of over 1700 MPa. The Zr70Al7（Ni1/3Cu2/3）23 BMG exhibits a large compressive plastic strain up to 21% and a high notch toughness value of 60.6 MPa m1/2. The increase in Zr content results in the decrease in GFA and thermostability, and in the improvement of plasticity under compressive and three-point bending conditions. The superior plasticity of high-zirconium BMGs is at- tributed to their high Poisson＇s ratio and small elastic modulus ratioμl/B.展开更多
Zr-based bulk metallic glass(BMG) composites with in situ formed Y 2 O 3 particle reinforcements were synthesized by proper additions of Y to ultrahigh-oxygen-containing glass-forming alloy precursors.Microstructures,...Zr-based bulk metallic glass(BMG) composites with in situ formed Y 2 O 3 particle reinforcements were synthesized by proper additions of Y to ultrahigh-oxygen-containing glass-forming alloy precursors.Microstructures,thermal stabilities,and mechanical properties of the composites were investigated.Glass formation was greatly enhanced by Y additions in the alloys and the resultant particles were homogenously distributed in the glassy matrix,allowing for the fabrication of oxide dispersion strengthened BMG composites.The compressive strength and hardness increased by 10% and 20%,respectively,with the introduction of Y 2 O 3 particles.These results are significant for the design and production of Zr-based BMGs and BMG composites with improved properties using commercial high-oxygen content raw materials under industrial conditions.展开更多
文摘In this paper, high-zirconium Zr66＋2xAl9-x（Ni1/3Cu2/3）25-x （x=0,1,2 at.%） bulk metallic glasses with high strength and large duc- tility were fabricated by copper mould casting. The effects of zirconium content on the glass-forming ability （GFA）, thermal properties and mechanical properties were investigated using X-ray diffractometer （XRD）, differential scanning calorimeter （DSC）, and mechanical testing system in compressive and three-point bending modes, respectively. The high-zirconium BMGs show the critical diameters of 3-5 ram, the supercooled liquid region ranging from 70 K to 99 K, and the yield strength of over 1700 MPa. The Zr70Al7（Ni1/3Cu2/3）23 BMG exhibits a large compressive plastic strain up to 21% and a high notch toughness value of 60.6 MPa m1/2. The increase in Zr content results in the decrease in GFA and thermostability, and in the improvement of plasticity under compressive and three-point bending conditions. The superior plasticity of high-zirconium BMGs is at- tributed to their high Poisson＇s ratio and small elastic modulus ratioμl/B.
基金supported by the National Basic Research Program of China (2007CB613900)the National Natural Science Foundation of China(51071008)the Innovation Foundation of BUAA for PhD Graduate sand Fundamental Research Funds for the Central Universities
文摘Zr-based bulk metallic glass(BMG) composites with in situ formed Y 2 O 3 particle reinforcements were synthesized by proper additions of Y to ultrahigh-oxygen-containing glass-forming alloy precursors.Microstructures,thermal stabilities,and mechanical properties of the composites were investigated.Glass formation was greatly enhanced by Y additions in the alloys and the resultant particles were homogenously distributed in the glassy matrix,allowing for the fabrication of oxide dispersion strengthened BMG composites.The compressive strength and hardness increased by 10% and 20%,respectively,with the introduction of Y 2 O 3 particles.These results are significant for the design and production of Zr-based BMGs and BMG composites with improved properties using commercial high-oxygen content raw materials under industrial conditions.
