The semisolid A356 alloy strip was prepared by a novel continuous micro fused-casting process. The microstructure evolution and mechanical property of A356 aluminum alloy strip with different nozzle temperatures were ...The semisolid A356 alloy strip was prepared by a novel continuous micro fused-casting process. The microstructure evolution and mechanical property of A356 aluminum alloy strip with different nozzle temperatures were investigated. The nozzle temperature had great influences on the microstructure and property primarily accompanied with the crystal change in the fused-casting area through the cooling conditions. The results showed that the semisolid A356 alloy strip samples fabricated by micro fused-casting demonstrated good performances and uniform structures with the nozzle temperature at 593 ℃ and the stirring velocity at 700 r/min. The fine grains of the primary α-Al phase with average grain size of 51 μm and shape factor up to 0.71 were obtained under the micro fused-casting process, and the ultimate average vickers hardness came up to 83.39±0.89 HV, and the tensile strength and elongation of the A356 alloy strip reached 245.32 MPa and 7.85%, respectively.展开更多
A novel semisolid micro fused-casting(MFC) for preparing A356 alloy strips is proposed, and the effects of process parameters of pouring temperature on the microstructure and properties of A356 alloy strips are invest...A novel semisolid micro fused-casting(MFC) for preparing A356 alloy strips is proposed, and the effects of process parameters of pouring temperature on the microstructure and properties of A356 alloy strips are investigated. MFC means that the semisolid metal slurry was pressed out from the outlet of bottom of crucible to the movable plate, and directly solidified and formed layer by layer. The microstructure and properties of A356 semisolid alloy slurry were influenced by the cooling conditions. Results show that the aluminu alloy A356 strip samples fabricated by micro fused-casting had good performances and uniform structures with the pouring temperature at 595 ℃ and the substrate movement speed at 18 mm/s. The fine grains of the primary a-Al phase with average grain size of 53 μm and shape factor up to 0.72 was obtained, the ultimate tensile strength of the aluminum alloy A356 strip reaches 243.79±3.91 MPa, while the average vickers hardness is 82.65±1.86 HV.展开更多
A novel semisolid continuous Micro Fused-Casting additive manufacturing technology for producing a ZL101 alloy strip was developed, Micro Fused-Casting means that the semisolid metal slurry was pressed out from the ou...A novel semisolid continuous Micro Fused-Casting additive manufacturing technology for producing a ZL101 alloy strip was developed, Micro Fused-Casting means that the semisolid metal slurry was pressed out from the outlet of bottom of crucible to the movable plate. The degree of sub-cooling was easily provided by movement of substrate in the micro fused-casting area. Under the aid of 3 D manufacturing software, the ZL101 alloy strip was solidified and formed layer by layer. The microstructure and properties of ZL101 semisolid slurry were improved by the cooling conditions. The results showed that the ZL101 alloy strip samples fabricated by Micro Fused-Casting had uniform structures and good performances with the substrate movement speed at 20 mm/s and the temperature at 590 ℃, the ultimate tensile strength and elongation of the ZL101 alloy strip reached 242.59 MPa and 7.71%, while the average Vickers hardness was 82.55 HV.展开更多
A novel micro fused-casting(MFC)process is developed for semisolid aluminum alloy slurry.The microstructure evolution and properties of semisolid ZL101 aluminum alloy slurry with difierent pouring temperature by MFC a...A novel micro fused-casting(MFC)process is developed for semisolid aluminum alloy slurry.The microstructure evolution and properties of semisolid ZL101 aluminum alloy slurry with difierent pouring temperature by MFC are investigated in this paper.During the cooling process,the effects of the pouring temperature on microstructure and properties is primarily analyzed.The microstructure of the semisolid ZL101 aluminum alloy is more homogeneous and the grain is smaller under proper pouring temperature.Temperature of liquids and solids of ZL101 aluminum alloy is measured by difierential scanning calorimetry(DSC).Distribution and characteristics of the microstructure of samples are examined by optical microscope(OM),scanning electron microscopy(SEM)equipped with energy dispersive spectrometer(EDS).The results show that the ZL101 semisolid slurry fabricated by MFC presents uniform shape and good grain size under the pouring temperature of 594°C and the stirring velocity of 600 r/min,and the fine grains of the primary a-Al phase with average grain size of 55μm and shape factor up to 0.67 were obtained.Besides,the ultimate tensile strength and the average Vickers hardness for semisolid ZL101 aluminum slurry are 178.19±1.37 MPa and 86.15±1.16 HV,respectively.展开更多
目的 观察真实世界益气活血法治疗脑梗死气虚血瘀证的疗效及影响因素。方法 本研究纳入2019年1月至2023年2月于北京中医药大学东直门医院通州院区脑病科就诊的226例脑梗死气虚血瘀证患者,给予中药益气活血法(补阳还五汤或小续命汤加减)...目的 观察真实世界益气活血法治疗脑梗死气虚血瘀证的疗效及影响因素。方法 本研究纳入2019年1月至2023年2月于北京中医药大学东直门医院通州院区脑病科就诊的226例脑梗死气虚血瘀证患者,给予中药益气活血法(补阳还五汤或小续命汤加减)治疗2周后观察美国国立卫生研究院卒中量表(National Institute of Health stroke scale, NIHSS)评分、改良Rankin评分(Modified Rankin scale,MRS)和日常生活活动能力表评分(Barthel Index of Activities of Daily Living, BI)并进行疗效的多因素分析。结果 中药益气活血法可改善脑梗死气虚血瘀证患者的NIHSS评分、MRS评分和BI评分,而影响NIHSS评分、MRS评分和BI评分的主要因素为年龄、合并疾病数量、基线MRS评分和BI评分。合并高血压影响NIHSS评分疗效,合并高血压、冠状动脉粥样硬化性心脏病、高脂血症和糖尿病等对MRS评分疗效无影响。结论 患者年龄、合并疾病数量、基线MRS评分、基线BI评分是影响中药益气活血法治疗脑梗死气虚血瘀证疗效的因素。展开更多
基金Funded by the National Natural Science Foundation of China(No.51341009)。
文摘The semisolid A356 alloy strip was prepared by a novel continuous micro fused-casting process. The microstructure evolution and mechanical property of A356 aluminum alloy strip with different nozzle temperatures were investigated. The nozzle temperature had great influences on the microstructure and property primarily accompanied with the crystal change in the fused-casting area through the cooling conditions. The results showed that the semisolid A356 alloy strip samples fabricated by micro fused-casting demonstrated good performances and uniform structures with the nozzle temperature at 593 ℃ and the stirring velocity at 700 r/min. The fine grains of the primary α-Al phase with average grain size of 51 μm and shape factor up to 0.71 were obtained under the micro fused-casting process, and the ultimate average vickers hardness came up to 83.39±0.89 HV, and the tensile strength and elongation of the A356 alloy strip reached 245.32 MPa and 7.85%, respectively.
文摘A novel semisolid micro fused-casting(MFC) for preparing A356 alloy strips is proposed, and the effects of process parameters of pouring temperature on the microstructure and properties of A356 alloy strips are investigated. MFC means that the semisolid metal slurry was pressed out from the outlet of bottom of crucible to the movable plate, and directly solidified and formed layer by layer. The microstructure and properties of A356 semisolid alloy slurry were influenced by the cooling conditions. Results show that the aluminu alloy A356 strip samples fabricated by micro fused-casting had good performances and uniform structures with the pouring temperature at 595 ℃ and the substrate movement speed at 18 mm/s. The fine grains of the primary a-Al phase with average grain size of 53 μm and shape factor up to 0.72 was obtained, the ultimate tensile strength of the aluminum alloy A356 strip reaches 243.79±3.91 MPa, while the average vickers hardness is 82.65±1.86 HV.
基金Funded by the National Natural Science Foundation of China(No.51341009)
文摘A novel semisolid continuous Micro Fused-Casting additive manufacturing technology for producing a ZL101 alloy strip was developed, Micro Fused-Casting means that the semisolid metal slurry was pressed out from the outlet of bottom of crucible to the movable plate. The degree of sub-cooling was easily provided by movement of substrate in the micro fused-casting area. Under the aid of 3 D manufacturing software, the ZL101 alloy strip was solidified and formed layer by layer. The microstructure and properties of ZL101 semisolid slurry were improved by the cooling conditions. The results showed that the ZL101 alloy strip samples fabricated by Micro Fused-Casting had uniform structures and good performances with the substrate movement speed at 20 mm/s and the temperature at 590 ℃, the ultimate tensile strength and elongation of the ZL101 alloy strip reached 242.59 MPa and 7.71%, while the average Vickers hardness was 82.55 HV.
基金Funded by the National Natural Science Foundation of China(No.51341009)。
文摘A novel micro fused-casting(MFC)process is developed for semisolid aluminum alloy slurry.The microstructure evolution and properties of semisolid ZL101 aluminum alloy slurry with difierent pouring temperature by MFC are investigated in this paper.During the cooling process,the effects of the pouring temperature on microstructure and properties is primarily analyzed.The microstructure of the semisolid ZL101 aluminum alloy is more homogeneous and the grain is smaller under proper pouring temperature.Temperature of liquids and solids of ZL101 aluminum alloy is measured by difierential scanning calorimetry(DSC).Distribution and characteristics of the microstructure of samples are examined by optical microscope(OM),scanning electron microscopy(SEM)equipped with energy dispersive spectrometer(EDS).The results show that the ZL101 semisolid slurry fabricated by MFC presents uniform shape and good grain size under the pouring temperature of 594°C and the stirring velocity of 600 r/min,and the fine grains of the primary a-Al phase with average grain size of 55μm and shape factor up to 0.67 were obtained.Besides,the ultimate tensile strength and the average Vickers hardness for semisolid ZL101 aluminum slurry are 178.19±1.37 MPa and 86.15±1.16 HV,respectively.
文摘目的 观察真实世界益气活血法治疗脑梗死气虚血瘀证的疗效及影响因素。方法 本研究纳入2019年1月至2023年2月于北京中医药大学东直门医院通州院区脑病科就诊的226例脑梗死气虚血瘀证患者,给予中药益气活血法(补阳还五汤或小续命汤加减)治疗2周后观察美国国立卫生研究院卒中量表(National Institute of Health stroke scale, NIHSS)评分、改良Rankin评分(Modified Rankin scale,MRS)和日常生活活动能力表评分(Barthel Index of Activities of Daily Living, BI)并进行疗效的多因素分析。结果 中药益气活血法可改善脑梗死气虚血瘀证患者的NIHSS评分、MRS评分和BI评分,而影响NIHSS评分、MRS评分和BI评分的主要因素为年龄、合并疾病数量、基线MRS评分和BI评分。合并高血压影响NIHSS评分疗效,合并高血压、冠状动脉粥样硬化性心脏病、高脂血症和糖尿病等对MRS评分疗效无影响。结论 患者年龄、合并疾病数量、基线MRS评分、基线BI评分是影响中药益气活血法治疗脑梗死气虚血瘀证疗效的因素。
