The present work is devoted to the development of Fe-（B-Si）-Zr amorphous alloys with high glass-forming ability and good magnetic properties. Using the cluster-plus-glue-atom model proposed for ideal amorphous struc...The present work is devoted to the development of Fe-（B-Si）-Zr amorphous alloys with high glass-forming ability and good magnetic properties. Using the cluster-plus-glue-atom model proposed for ideal amorphous structures, [FeFe11B3Si]（Fe1-xZrx） was determined as the cluster formula of Fe-（B-Si）-Zr alloys. The glass formation and thermal stability of the serial alloys, namely, [FeFel^B3Si]（Fel_xZrx） （x = 0, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.75, and 1.0）, were studied by the combination of copper mold casting, X-ray diffraction, and differential thermal analysis techniques. The maxima of glass-forming ability and thermal stability were found to occur at the compositions of [FeFe11B3Si] （Fe0.6Zr0.4） and [FeFe11B3Si]（Fe0.5Zr0.5）. The alloys can be cast into amorphous rods with 1.5 ram diameter, and upon reheating, the amorphous alloys exhibit a large undercooled liquid span of 37 K. The saturation magnetization of the [FeFe11B3Si]（Fe0.5Zr0.5） amorphous alloy was measured to be 1.4 T.展开更多
Mg-Gd-Y-Zr alloys with high strength fall within narrow composition range.The present paper explains their composition rule by establishing the cluster-plus-glue-atom unit of Gd-containing Mg solid solution with the a...Mg-Gd-Y-Zr alloys with high strength fall within narrow composition range.The present paper explains their composition rule by establishing the cluster-plus-glue-atom unit of Gd-containing Mg solid solution with the aid of Mg matrix and Mg_(5) Gd precipitate phase.First,based on the structural homologue between Gd-containing Mg solid solution and Mg_(5) Gd precipitate phase and in combination with our previously established method for calculating the glue atoms,[Gd-Mg_(12)]Mg_(5) is obtained as the chemical unit of Gd-containing Mg solid solution.Then,seven compositions are designed using different combinations of this unit and that of pure Mg[Mg-Mg_(12)Mg3.After a systematic experimental investigation on the microstructure and mechanical property evolutions as a function of the unit proportions,it is revealed that the Mg-10.1 Gd-3.3 Y-0.9 Zr alloy,being issued from equi-proportion mixing of the two units,shows the strongest tendency of precipitation and reaches the highest strength of 374 MPa after aging.The composition and strength of this alloy are quite close to GW103 K which is well recognized for its general mechanical performance in Mg-Gd-Y-Zr system.展开更多
The alloying effects of the like-atom substitution of Ni and Co for Fe on the various properties of Fe_（70）B_（16.7）Si_（8.3）Ta_5 metallic glass are investigated in this present work. New Fe-based bulk glassy allo...The alloying effects of the like-atom substitution of Ni and Co for Fe on the various properties of Fe_（70）B_（16.7）Si_（8.3）Ta_5 metallic glass are investigated in this present work. New Fe-based bulk glassy alloys, namely Fe_（60–x）Co_xNi_（10）B_（16.7）Si_（8.3）Ta_5（at.%;x = 10, 20 and 30） with critical diameters up to 1.5 mm, were made by means of copper mold casting.A new glass-forming ability indicator, viz., the enthalpy of supercooled liquid, has been introduced for assessment of the glass-forming abilities（GFAs） of these Fe-based multi-component alloys. Nano-indentation results indicate that the calculated elastic modulus and hardness of the bulk glassy alloys are lower than those of the Fe_（70）B_（16.7）Si_（8.3）Ta_5 alloy.Among these bulk glassy alloys, Fe_（70）B_（16.7）Si_（8.3）Ta_5 exhibits the large elastic modulus and hardness with values of 178 ± 1GPa and 12.9 ± 0.1 GPa, respectively. All the bulk glassy alloys exhibit good soft magnetic properties with high saturation magnetization Bs^0.75–1.04 T but low coercive force Hc^0.2–5.2 A/m.展开更多
The present work is devoted to investigating the microstructure,magnetism and magnetocaloric effects of Si- and Mn-rich FeMn(P,Si) alloys.The Mn-substituted alloys with Fe_(2-x)Mn_xP_(0.4)Si_(0.6)(x=1.25,1.30,1.35,1.4...The present work is devoted to investigating the microstructure,magnetism and magnetocaloric effects of Si- and Mn-rich FeMn(P,Si) alloys.The Mn-substituted alloys with Fe_(2-x)Mn_xP_(0.4)Si_(0.6)(x=1.25,1.30,1.35,1.40,1.45 and 1.50) were prepared by high-energy ball milling and solid-state reaction.Experimental results show that the alloys crystallized into a majority Fe_2P-type hexagonal structure,coexisting with minor amounts of(Mn,Fe)_3Si and(Mn,Fe)_5Si_3 phases.The Curie temperature decreased linearly from 321 to 266 K with increasing Mn content from 1.25 to 1.50 in Fe_(2-x)Mn_xP_(0.4)Si_(0.6) alloys.The first-order magnetic phase transition became weakened and the second-order magnetic phase transition became dominated with increasing Mn content.Fe_(0.75)Mn_(1.25)P_(0.4)Si_(0.6) alloy presents a maximum isothermal magnetic-entropy changes of 7.2 J(kg K)^(-1) in a magnetic field change of 0-1.5 T.The direct measurement shows that Fe_(0.7)Mn_(1.3)P_(0.4)Si_(0.6) and Fe_(0.65)Mn_(1.35)P_(0.4)Si_(0.6) alloys exhibit a maximum adiabatic temperature change of 1.8 K in a magnetic field change of 0-1.48 T.The thermal hysteresis for all alloys is less than 4 K.These experimental results reveal that Fe_(2-x)Mn_xP_(0.4)Si_(0.6) alloys could be a candidate material for magnetic refrigeration.展开更多
Composition homogenization in solid solution is important for industrial alloys. In the present work, a solute homogenization model is proposed based on the chemical short-range-order tendency in Mg-Gd- based alloys. ...Composition homogenization in solid solution is important for industrial alloys. In the present work, a solute homogenization model is proposed based on the chemical short-range-order tendency in Mg-Gd- based alloys. After a calculation using the cluster-plus-glue-atom model, the stable Mg-Gd structural unit is derived, [Gd-Mg12 ]Mg6, where one solute Gd is nearest-neighbored with twelve Mg atoms to form the characteristic hcp cluster [Gd-Mg12 ] and this cluster is matched with six Mg glue atoms. Such a local unit is then mixed with [Mg-Mg12 ]Mg3, the stable unit for pure Mg. Assuming that the Gd-containing units are arranged in fcc- or bcc-like lattice points and the Mg units in their octahedral interstices, three proportions between the two units are obtained, 1：1, 2：3, and 1：3, which constitute three solute homogenization modes. The prevailing Mg-Gd-based alloys are consequently classified into three groups, respectively exemplified by GW103 K （Mg-10Gd-3Y-0.4Zr, wt%）, GW83 K （Mg-SGd-3Y-0.4Zr）, and GW63 K （Mg-6Gd- 3Y-0.4Zr）. Mg-Gd-Y-Zr alloys were designed following the model （where Y and Zr were also added in substitution for Gd） and prepared by permanent-mould casting. According to their mechanical properties, the 1：3 alloy （Mg-5.9Gd-1.6Y-0.4Zr） shows the best comprehensive properties （ultimate tensile strength 305 MPa, yield strength 186 MPa, elongation 9.0%） in solution plus ageing state.2017 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science ＆ Technology.展开更多
A series of Zr_(63.5-x)Ti_(x)Al_(9)Fe_(4.5)Cu_(23)(x=0,1.5,3.0,4.5,6.0;at%) bulk metallic glasses(BMGs) were designed and produced by means of copper mold suction casting.The effect of Ti addition on the glass-forming...A series of Zr_(63.5-x)Ti_(x)Al_(9)Fe_(4.5)Cu_(23)(x=0,1.5,3.0,4.5,6.0;at%) bulk metallic glasses(BMGs) were designed and produced by means of copper mold suction casting.The effect of Ti addition on the glass-forming ability(GFA) and mechanical properties of Zr_(63.5-x)Ti_(x)Al_(9)Fe_(4.5)Cu_(23) alloys was first investigated.The glassforming ability and room-temperature plasticity of BMGs increase first and then reduced with Ti content increasing.At x=3.0,the Zr_(60.5)Ti_(3)Al_(9)Fe_(4.5)Cu_(23) BMG showed a critical glass formation diameter of 10 mm and excellent room-temperature compressive plasticity(εP=4.7%) by using the samples with dimensions of Φ3 mm × 6 mm.Meanwhile,the BMG also showed better biocompatibility and biocorrosion resistance compared with Ti6 A14 V alloy.Under the imitated human body condition,the corrosion current density(Icorr) of BMG was 6.61 × 10^(-10) A·cm^(-2),which is two orders of magnitude lower than that of conventional Ti6Al4V alloy.Moreover,the CCD-986 sk cell viabilities are,respectively,65.4% and 46.6% on the BMG and Ti6 A14 V alloy,indicating better biocompatibility of BMG.The Zr_(60.5)Ti_(3)Al_(9)Fe_(4.5)Cu_(23) BMG with larger GFA,excellent mechanical properties,biocompatibility and biocorrosion resistance is considered as a potential material in biomedical device fields.展开更多
Bulk amorphous formation in Ti-Cu-based multicomponent alloys, free of Ni, Pd and Be elements, were studied using the cluster-plus-glue-atom model. The basic cluster formula was revealed as [Ti9Cu6]Cu3 to explain the ...Bulk amorphous formation in Ti-Cu-based multicomponent alloys, free of Ni, Pd and Be elements, were studied using the cluster-plus-glue-atom model. The basic cluster formula was revealed as [Ti9Cu6]Cu3 to explain the best binary glass forming composition Ti50Cu50=Ti9Cu9, where the CN14 rhombi-dodecahedron Ti9Cu6 was the principal cluster in the devitrification phase CuTi. This basic cluster formula was further alloyed with Zr and Sn and a critical glass forming ability was reached at （Ti7.2Zr1.8）（Cus.72Sn0.28） and （Ti7.2Zr1.8）（Cu8.45Sn0.55） up to 5 mm in diameter by suction casting, which was the largest in Ti-Cu- based and Ni-, Pd- and Be-free alloys.展开更多
基金financially supported by the Natural Science Foundation of China (Nos. 51131002, 51041011 and 50901012)the Fundamental Research Funds for the Central Universities (No. DUT12LAB08)the Scientific Research Foundation for the Returned Overseas Chinese Scholars by the Ministry of Education of China
文摘The present work is devoted to the development of Fe-（B-Si）-Zr amorphous alloys with high glass-forming ability and good magnetic properties. Using the cluster-plus-glue-atom model proposed for ideal amorphous structures, [FeFe11B3Si]（Fe1-xZrx） was determined as the cluster formula of Fe-（B-Si）-Zr alloys. The glass formation and thermal stability of the serial alloys, namely, [FeFel^B3Si]（Fel_xZrx） （x = 0, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.75, and 1.0）, were studied by the combination of copper mold casting, X-ray diffraction, and differential thermal analysis techniques. The maxima of glass-forming ability and thermal stability were found to occur at the compositions of [FeFe11B3Si] （Fe0.6Zr0.4） and [FeFe11B3Si]（Fe0.5Zr0.5）. The alloys can be cast into amorphous rods with 1.5 ram diameter, and upon reheating, the amorphous alloys exhibit a large undercooled liquid span of 37 K. The saturation magnetization of the [FeFe11B3Si]（Fe0.5Zr0.5） amorphous alloy was measured to be 1.4 T.
基金financially supported by the National Key Research and Development Program of China(No.2016YFB0701201)the Natural Science Foundation of China(No.11674045)。
文摘Mg-Gd-Y-Zr alloys with high strength fall within narrow composition range.The present paper explains their composition rule by establishing the cluster-plus-glue-atom unit of Gd-containing Mg solid solution with the aid of Mg matrix and Mg_(5) Gd precipitate phase.First,based on the structural homologue between Gd-containing Mg solid solution and Mg_(5) Gd precipitate phase and in combination with our previously established method for calculating the glue atoms,[Gd-Mg_(12)]Mg_(5) is obtained as the chemical unit of Gd-containing Mg solid solution.Then,seven compositions are designed using different combinations of this unit and that of pure Mg[Mg-Mg_(12)Mg3.After a systematic experimental investigation on the microstructure and mechanical property evolutions as a function of the unit proportions,it is revealed that the Mg-10.1 Gd-3.3 Y-0.9 Zr alloy,being issued from equi-proportion mixing of the two units,shows the strongest tendency of precipitation and reaches the highest strength of 374 MPa after aging.The composition and strength of this alloy are quite close to GW103 K which is well recognized for its general mechanical performance in Mg-Gd-Y-Zr system.
基金supported by the National Natural Science Foundation of China(Nos.51671045 and 51601073)the State Key Laboratory of Solidification Processing in NWPU(No.SKLSP201607)the Start-up Cost in Jiangsu University of Science and Technology(No.1062931608)
文摘The alloying effects of the like-atom substitution of Ni and Co for Fe on the various properties of Fe_（70）B_（16.7）Si_（8.3）Ta_5 metallic glass are investigated in this present work. New Fe-based bulk glassy alloys, namely Fe_（60–x）Co_xNi_（10）B_（16.7）Si_（8.3）Ta_5（at.%;x = 10, 20 and 30） with critical diameters up to 1.5 mm, were made by means of copper mold casting.A new glass-forming ability indicator, viz., the enthalpy of supercooled liquid, has been introduced for assessment of the glass-forming abilities（GFAs） of these Fe-based multi-component alloys. Nano-indentation results indicate that the calculated elastic modulus and hardness of the bulk glassy alloys are lower than those of the Fe_（70）B_（16.7）Si_（8.3）Ta_5 alloy.Among these bulk glassy alloys, Fe_（70）B_（16.7）Si_（8.3）Ta_5 exhibits the large elastic modulus and hardness with values of 178 ± 1GPa and 12.9 ± 0.1 GPa, respectively. All the bulk glassy alloys exhibit good soft magnetic properties with high saturation magnetization Bs^0.75–1.04 T but low coercive force Hc^0.2–5.2 A/m.
基金supported by the National Natural Science Foundation of China(51671045 and 51601073)the Fundamental Research Funds for the Central Universities(DUT16ZD209)+1 种基金the National Magnetic Confinement Fusion Science Program(2013GB107003 and 2015GB105003)the State Key Laboratory of Solidification Processing in Northwestern Polytechnical University(SKLSP201607)
文摘The present work is devoted to investigating the microstructure,magnetism and magnetocaloric effects of Si- and Mn-rich FeMn(P,Si) alloys.The Mn-substituted alloys with Fe_(2-x)Mn_xP_(0.4)Si_(0.6)(x=1.25,1.30,1.35,1.40,1.45 and 1.50) were prepared by high-energy ball milling and solid-state reaction.Experimental results show that the alloys crystallized into a majority Fe_2P-type hexagonal structure,coexisting with minor amounts of(Mn,Fe)_3Si and(Mn,Fe)_5Si_3 phases.The Curie temperature decreased linearly from 321 to 266 K with increasing Mn content from 1.25 to 1.50 in Fe_(2-x)Mn_xP_(0.4)Si_(0.6) alloys.The first-order magnetic phase transition became weakened and the second-order magnetic phase transition became dominated with increasing Mn content.Fe_(0.75)Mn_(1.25)P_(0.4)Si_(0.6) alloy presents a maximum isothermal magnetic-entropy changes of 7.2 J(kg K)^(-1) in a magnetic field change of 0-1.5 T.The direct measurement shows that Fe_(0.7)Mn_(1.3)P_(0.4)Si_(0.6) and Fe_(0.65)Mn_(1.35)P_(0.4)Si_(0.6) alloys exhibit a maximum adiabatic temperature change of 1.8 K in a magnetic field change of 0-1.48 T.The thermal hysteresis for all alloys is less than 4 K.These experimental results reveal that Fe_(2-x)Mn_xP_(0.4)Si_(0.6) alloys could be a candidate material for magnetic refrigeration.
基金supported financially by the National Key Research and Development Program of China (No. 2016YFB0701201)the Natural Science Foundation of China (No. 11674045)
文摘Composition homogenization in solid solution is important for industrial alloys. In the present work, a solute homogenization model is proposed based on the chemical short-range-order tendency in Mg-Gd- based alloys. After a calculation using the cluster-plus-glue-atom model, the stable Mg-Gd structural unit is derived, [Gd-Mg12 ]Mg6, where one solute Gd is nearest-neighbored with twelve Mg atoms to form the characteristic hcp cluster [Gd-Mg12 ] and this cluster is matched with six Mg glue atoms. Such a local unit is then mixed with [Mg-Mg12 ]Mg3, the stable unit for pure Mg. Assuming that the Gd-containing units are arranged in fcc- or bcc-like lattice points and the Mg units in their octahedral interstices, three proportions between the two units are obtained, 1：1, 2：3, and 1：3, which constitute three solute homogenization modes. The prevailing Mg-Gd-based alloys are consequently classified into three groups, respectively exemplified by GW103 K （Mg-10Gd-3Y-0.4Zr, wt%）, GW83 K （Mg-SGd-3Y-0.4Zr）, and GW63 K （Mg-6Gd- 3Y-0.4Zr）. Mg-Gd-Y-Zr alloys were designed following the model （where Y and Zr were also added in substitution for Gd） and prepared by permanent-mould casting. According to their mechanical properties, the 1：3 alloy （Mg-5.9Gd-1.6Y-0.4Zr） shows the best comprehensive properties （ultimate tensile strength 305 MPa, yield strength 186 MPa, elongation 9.0%） in solution plus ageing state.2017 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science ＆ Technology.
基金supported by the National Natural Science Foundation of China (Nos.51901116 and 51671045)the Science Challenge Project (No.TZ2016004)+1 种基金the Fundamental Research Funds for the Central Universities (Nos.DUT16ZD209 and DUT18GF112)the National Magnetic-Confinement Fusion Science Program (Nos.2013GB107003 and 2015GB105003)。
文摘A series of Zr_(63.5-x)Ti_(x)Al_(9)Fe_(4.5)Cu_(23)(x=0,1.5,3.0,4.5,6.0;at%) bulk metallic glasses(BMGs) were designed and produced by means of copper mold suction casting.The effect of Ti addition on the glass-forming ability(GFA) and mechanical properties of Zr_(63.5-x)Ti_(x)Al_(9)Fe_(4.5)Cu_(23) alloys was first investigated.The glassforming ability and room-temperature plasticity of BMGs increase first and then reduced with Ti content increasing.At x=3.0,the Zr_(60.5)Ti_(3)Al_(9)Fe_(4.5)Cu_(23) BMG showed a critical glass formation diameter of 10 mm and excellent room-temperature compressive plasticity(εP=4.7%) by using the samples with dimensions of Φ3 mm × 6 mm.Meanwhile,the BMG also showed better biocompatibility and biocorrosion resistance compared with Ti6 A14 V alloy.Under the imitated human body condition,the corrosion current density(Icorr) of BMG was 6.61 × 10^(-10) A·cm^(-2),which is two orders of magnitude lower than that of conventional Ti6Al4V alloy.Moreover,the CCD-986 sk cell viabilities are,respectively,65.4% and 46.6% on the BMG and Ti6 A14 V alloy,indicating better biocompatibility of BMG.The Zr_(60.5)Ti_(3)Al_(9)Fe_(4.5)Cu_(23) BMG with larger GFA,excellent mechanical properties,biocompatibility and biocorrosion resistance is considered as a potential material in biomedical device fields.
基金supported by the National Natural Science Foundation of China(Grant Nos. 51131002 and 51171035)the Fundamental Research Funds for the Central Universities(Grant No. DUT12LAB08)
文摘Bulk amorphous formation in Ti-Cu-based multicomponent alloys, free of Ni, Pd and Be elements, were studied using the cluster-plus-glue-atom model. The basic cluster formula was revealed as [Ti9Cu6]Cu3 to explain the best binary glass forming composition Ti50Cu50=Ti9Cu9, where the CN14 rhombi-dodecahedron Ti9Cu6 was the principal cluster in the devitrification phase CuTi. This basic cluster formula was further alloyed with Zr and Sn and a critical glass forming ability was reached at （Ti7.2Zr1.8）（Cus.72Sn0.28） and （Ti7.2Zr1.8）（Cu8.45Sn0.55） up to 5 mm in diameter by suction casting, which was the largest in Ti-Cu- based and Ni-, Pd- and Be-free alloys.
