检索结果-南通市图书馆

Microstructure evolution,mechanical properties and fracture behavior of Al-xSi/AZ91D bimetallic composites prepared by a compound casting

引用

Journal of Magnesium and Alloys 2024年第5期12卷 1944-1964页

作者： Guangyu Li wenming jiang Feng Guan Junwen Zhu Yang Yu Zitian Fan State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China

In this paper,the effect of the Si content on microstructure evolution,mechanical properties,and fracture behavior of the Al-xSi/AZ91D bimetallic composites prepared by compound casting was investigated *** obtained results showed that all the Al-xSi/AZ91D bimetallic composites had a metallurgical reaction layer(MRL),whose thickness increased with increasing Si content for the hypoeutectic Al-Si/AZ91D composites,while the hypereutectic Al-Si/AZ91D composites were *** MRL included eutectic layer(E layer),intermetallic compound layer(IMC layer)and transition region layer(T layer).In the IMC layer,the hypereutectic Al-Si/AZ91D composites contained some Si solid solution and flocculent Mg_(2)Si+Al-Mg IMCs phases not presented in the hypoeutectic Al-Si/AZ91D ***,increasing Si content,the thickness proportion of the T layer increased,forming an inconsistent preferred orientation of the *** shear strengths of the Al-xSi/AZ91D bimetallic composites enhanced with increasing Si content,and the Al-15Si/AZ91D composite obtained a maximum shear strength of 58.6 MPa,which was 73.4% higher than the Al-6Si/AZ91D *** fractures of the Al-xSi/AZ91D bimetallic composites transformed from the T layer into the E layer with the increase of the Si *** improvement of the shear strength of the Al-xSi/AZ91D bimetallic composites was attributed to the synergistic action of the Mg_(2)Si particle reinforcement,the reduction of oxidizing inclusions and the ratio of Al-Mg IMCs as well as the orientation change of the MRL.

关键词： Al/Mg bimetallic composites Si content Mg_(2)Si reinforcement Microstructure Mechanical properties Fracture behavior

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Novel technologies for the lost foam casting process

引用

Frontiers of Mechanical Engineering 2018年第1期13卷 37-47页

作者： wenming jiang Zitian FAN State Key Laboratory of Material Processing and Die & MouldTechnology Huazhong University of Science and Technology Wuhan430074 China

Lost foam casting （LFC） is a green precision casting process categorized as a near net forming technology. Yet, despite its popularity, it still suffers from some technological problems, such as poor filling ability of the castings, coarse and non-dense microstructure, low mechanical properties for the A1 and Mg LFC processes, and defective carburization for the low carbon steel LFC process. These drawbacks restrict the development and widespread application of the LFC process. To solve these problems, the present study developed several novel LFC technologies, namely, LFC technologies under vacuum and low pressure, vibration solidification, and pressure solidification conditions; expendable shell casting techno- logy; and preparation technology of bimetallic castings based on the LFC process. The results showed that the LFC under vacuum and low pressure evidently improved the filling ability and solved the oxidization problem of the alloys, which is suitable for producing complex and thin- wall castings. The vibration and pressure solidifications increased the compactness of the castings and refined the microstructure, significantly improving the mechanical properties of the castings. The expendable shell casting technology could solve the pore, carburization, and inclusion defects of the traditional LFC method, obtaining castings with acceptable surface quality. Moreover, the A1/Mg and A1/A1 bimetallic castings with acceptable metallurgical bonding were successfully fabricated using the LFC process. These proposed novel LFC technologies can solve the current technological issues and promote the technological progress of the LFC process.

关键词： LFC under vacuum and low pressure vibra-tion solidification pressure solidification expendable shellcasting bimetallic castings

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Gating system optimization of low pressure casting A356 aluminum alloy intake manifold based on numerical simulation

引用

China Foundry 2014年第2期11卷 119-124页

作者： jiang wenming Fan Zitian School of Mechanical&Electrical Engineering Wuhan Institute of Technology State Key Laboratory of Material Processing and Die&Mould Technology Huazhong University of Science and Technology

To eliminate the shrinkage porosity in low pressure casting of an A356 aluminum alloy intake manifold casting, numerical simulation on fi lling and solidifi cation processes of the casting was carried out using the ProCAST software. The gating system of the casting is optimized according to the simulation results. Results show that when the gating system consists of only one sprue, the fi lling of the molten metal is not stable; and the casting does not follow the sequence solidifi cation, and many shrinkage porosities are observed through the casting. After the gating system is improved by adding one runner and two in-gates, the fi lling time is prolonged from 4.0 s to 4.5 s, the fi lling of molten metal becomes stable, but this casting does not follow the sequence solidifi cation either. Some shrinkage porosity is also observed in the hot spots of the casting. When the gating system was further improved by adding risers and chill to the hot spots of the casting, the shrinkage porosity defects were eliminated completely. Finally, by using the optimized gating system the A356 aluminum alloy intake manifold casting with integrated shape and smooth surface as well as dense microstructure was successfully produced.

关键词： low pressure casting A356 aluminum alloy numerical simulation optimization intake manifold

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

卧式紧凑型旋流气浮装置旋流筒结构优化数值模拟研究

引用

工业水处理 2024年第6期44卷 179-188页

作者：龚俊张磊谢勰海类游蒋文明中石化胜利油田海洋采油厂山东东营257237 中石化石油工程设计有限公司山东东营257026 长庆油田分公司规划计划部陕西西安710018 中国石油大学(华东)储运与建筑工程学院山东青岛266580

由于油田开发采出液含水率上升和海上平台空间的限制,亟需紧凑型污水处理设备用于对海上油田含油污水处理。对此设计了卧式紧凑型旋流气浮装置,通过Fluent数值模拟方法对该装置旋流筒区域的流场分布及油水分离性能开展了系统研究,探究... 详细信息

由于油田开发采出液含水率上升和海上平台空间的限制,亟需紧凑型污水处理设备用于对海上油田含油污水处理。对此设计了卧式紧凑型旋流气浮装置,通过Fluent数值模拟方法对该装置旋流筒区域的流场分布及油水分离性能开展了系统研究,探究了旋流筒结构、入口管径、含油污水入口速度和入口含油率等因素对油水分离效果的影响。结果表明,在入口管径为20 mm,含油污水入口速度为2 m/s时,采用导流叶片的旋流筒结构能获得较好的流场分布;含油污水入口速度越大切向速度衰减越严重;旋流筒在高度为100~300 mm时切向速度衰减较大,在高度为300~650 mm内衰减较小;相同含油污水入口速度下,增大入口管径能使旋流筒内油相体积分数增大;增大含油污水入口速度反而会导致旋流筒内油相体积分数减小;旋流筒内油相体积分数呈“U”型分布,且随入口含油率增大而增大,与入口含油率成正比。

关键词：紧凑型气浮装置气浮旋流结构优化数值模拟

来源：

维普期刊数据库博看期刊

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

L1_(2)型Al_(67)Cu_(8)Ti_(25)细化剂的制备及其对铝合金组织的影响

引用

特种铸造及有色合金 2024年第7期44卷 940-946页

作者：陈旭席卫国陈吉程婧璠蔡启舟蒋文明华中科技大学材料科学与工程学院材料成形与模具技术全国重点实验室武汉430074

采用单质粉末通过高能球磨和真空烧结制备了L1_(2)型Al_(67)Cu_(8)Ti_(25)金属间化合物,并将其破碎后与Al粉进行混合制备了Al-25Al_(67)Cu_(8)Ti_(25)复合细化剂。研究了球磨时间、烧结温度对制备L1_(2)型Al_(67)Cu_(8)Ti_(25)金属间化... 详细信息

采用单质粉末通过高能球磨和真空烧结制备了L1_(2)型Al_(67)Cu_(8)Ti_(25)金属间化合物,并将其破碎后与Al粉进行混合制备了Al-25Al_(67)Cu_(8)Ti_(25)复合细化剂。研究了球磨时间、烧结温度对制备L1_(2)型Al_(67)Cu_(8)Ti_(25)金属间化合物的影响。以纯铝和Al-5Cu-Mn铸造铝合金为对象,研究了复合细化剂对α-Al宏观和微观组织的影响及作用机制。结果表明,球磨粉末在600℃下烧结可制备单相的L1_(2)型Al_(67)Cu_(8)Ti_(25)化合物颗粒,随着球磨时间增加,烧结形成的化合物颗粒的平均尺寸减小至11μm,形貌趋于球形。Al-25Al_(67)Cu_(8)Ti_(25)复合细化剂对α-Al具有较好的细化效果,加入0.25%的Al_(67)Cu_(8)Ti_(25)细化剂后,纯铝及Al-5Cu-Mn合金的晶粒尺寸分别细化至224μm和137μm。L1_(2)型Al_(67)Cu_(8)Ti_(25)化合物是α-Al的有效形核质点,与α-Al的错配度为2.35%,相比于Al3Ti,其错配度更小,异质形核能力更强。

关键词： L1_(2)型Al_(67)Cu_(8)Ti_(25)金属间化合物显微组织晶粒细化异质形核

来源：

维普期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

旋流后置型超声速分离器激波控制方法数值模拟

引用

石油与天然气化工 2024年第4期53卷 8-18页

作者：蒋文明韩晨玉门惠云刘杨周媛媛山东省油气储运安全重点实验室中国石油大学(华东)储运与建筑工程学院中海石油(中国)有限公司天津分公司

目的超声速分离是一种基于收缩-扩张喷管的新型气体净化与燃料气加工技术。旋流后置型超声速分离器中的旋流器通常设置在扩压段前,易诱发正激波并破坏分离器内部低温环境,同时,激波难以控制。因此,拟通过优化超声速分离器结构的方式削... 详细信息

目的超声速分离是一种基于收缩-扩张喷管的新型气体净化与燃料气加工技术。旋流后置型超声速分离器中的旋流器通常设置在扩压段前,易诱发正激波并破坏分离器内部低温环境,同时,激波难以控制。因此,拟通过优化超声速分离器结构的方式削弱激波的影响。方法①基于热力学和空气动力学的原理,提出了一种适用于旋流后置型超声速分离器的激波控制理论;②根据该理论设计了一种能够控制激波的跨旋流结构,建立了该结构的普适性设计公式;③通过数值模拟研究,分析了跨旋流结构的倾斜角度、渐扩段长度、旋流器的叶片扭转角度3个重要结构参数对激波控制的影响。结果当跨旋流结构的倾斜角度为3.3°、渐扩段长度为107 mm、旋流器的叶片扭转角度为120°时,分离器具有最佳性能。结论相比传统的旋流后置型分离器,添加跨旋流结构可以保证流体流通面积在渐扩段持续增加,从而实现对激波的有效控制,以提高分离器的冷凝和分离效率。

关键词：超声速流动激波控制纯化旋流后置数值模拟跨旋流结构

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Enhanced mechanical properties of 6082 aluminum alloy via SiC addition combined with squeeze casting

引用

Journal of Materials Science & Technology 2021年第29期88卷 119-131页

作者： wenming jiang Junwen Zhu Guangyu Li Feng Guan Yang Yu Zitian Fan State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan430074China State Key Laboratory of High Performance Complex Manufacturing Central South University410083 ChangshaChina

In order to improve mechanical properties of 6082 aluminum alloy,the SiC_(p)/Al 6082 composites were prepared by the addition of the micron-sized SiC_(p)articles combined with the squeeze *** effects of the SiC_(p)content and squeeze casting on the microstructure and mechanical properties of the 6082 aluminum alloy were investigated by SEM,EDS,TEM,tensile testing and hardness testing analysis *** results exhibited that the SiC_(p)content and squeeze casting had a significant impact on the microstructure and mechanical properties of the 6082 aluminum *** addition of the SiC_(p)refined the grain size of the 6082 aluminum alloy while caused the increase of the porosity with increasing the SiC_(p)content,especially in the permanent mold casting *** to the permanent mold casting,the squeeze casting obviously reduced pore defects,refined grain size and made the SiC_(p)distribute evenly as well as bond tightly with the Al *** tensile strength,yield strength,elongation,elastic modulus and hardness of the 6082 aluminum alloy obtained with the SiC_(p)and squeeze casting were remarkably improved,and the optimal mechanical properties were obtained with a 2 wt.%SiC_(p),and they increased 10.73%,72.7%,193.9%,23.5%and 25.2%,respectively,compared to those of the6082 aluminum alloy obtained without SiC_(p)and squeeze *** fracture surface of the SiC_(p)/Al 6082 composites obtained with the squeeze casting was dense and exhibited a ductile fracture mode.

关键词： 6082 aluminum alloy SiC_(p) Aluminum matrix composites Squeeze casting Microstructure Mechanical properties

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Research on cracking mechanism of the thin shell mould in expendable pattern shell casting during pattern removal process

引用

China Foundry 2010年第3期7卷 230-235页

作者： jiang wenming Fan Zitian Liao Defeng Zhao Zhong State Key Laboratory of Material Processing and Die ＆ Mould Technology Huazhong University of Science and Technology Wuhan 430074 Hubei China

Aiming at the cracking phenomenon of the thin shell mould in the expendable pattern shell casting during the pattern removing process, some systemic researches are *** influence of the pattern removing method and temperature on the pattern removing were *** shell mould cracking mechanism was analyzed by using thermo-gravimetric analysis (TGA), and combining the temperature field and the volume change of the expanded polystyrene (EPS) foam pattern being *** results indicated that the shell mould was not easily cracked when the pattern removing process was carried out with the furnace being heated little by little because of the shell slowly shrinking with dehydration and shell strength gradually *** shell mould was soon destroyed when it was set directly into the furnace at above 400 oC because of the thin shell mould rapidly shrinking and the foam pattern ***, the shell mould had no cracking when it had been preheated for a long time even if the furnace temperature was above 400 oC and the shell was put into the furnace ***, when the shell mould was directly set into the furnace at lower temperatures, 250 to 300 ℃, the shell would shrink slowly and the foam pattern would stay at the maximum expansion stage temperature of 100 to 110 ℃ for a long time; and the shell mould would experience an expansion force from the foam pattern for a long *** expansion force is related to the pattern removing temperature, holding time, foam pattern thickness and ***, the foam pattern with higher density could make the shell crack.

关键词： expendable pattern shell casting pattern removing cracking shrinkage expansion force

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Influences of friction drag on spontaneous condensation in water vapor supersonic flows

引用

Science China(Technological Sciences) 2009年第9期52卷 2653-2659页

作者： jiang wenming LIU ZhongLiang LIU HengWei PANG HuiZhong BAO LingLing Education Ministry Key Lab of Enhanced Heat Transfer&Energy Conversation and Beijing Education Key Lab of Heat Transfer&Energy Conversion College of Environmental and Energy EngineeringBeijing University of TechnologyBeijing 100124China

A mathematical model was developed to investigate the water vapor spontaneous condensation under supersonic flow conditions. A numerical simulation was performed for the water vapor condensable supersonic flows through Laval nozzles under different flow friction conditions. The comparison between numerical and experimental results shows that the model is accurate enough to investigate the supersonic spontaneous condensation flow of water vapor inside Laval nozzles. The influences of flow friction drag on supersonic spontaneous condensation flow of water vapor inside Laval nozzles were investigated. It was found that the flow friction has a direct effect on the spontaneous condensation process and therefore it is important for an accurate friction prediction in designing this kind of Laval nozzles.

关键词： spontaneous condensation supersonic flow friction drag nozzle

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Improving mechanical properties of AZ91D magnesium/A356 aluminum bimetal prepared by compound casting via a high velocity oxygen fuel sprayed Ni coating

引用

Journal of Magnesium and Alloys 2022年第4期10卷 1075-1085页

In this paper,a Ni coating was deposited on the surface of the A356 aluminum alloy by high velocity oxygen fuel spraying to improve the performance of the AZ91D magnesium/A356 aluminum bimetal prepared by a compound *** effects of the Ni coating as well as its thickness on microstructure and mechanical properties of the AZ91D/A356 bimetal were systematically researched for the first *** demonstrated that the Ni coating and its thickness had a significant effect on the interfacial phase compositions and mechanical properties of the AZ91D/A356 *** 10μm’s Ni coating cannot prevent the generation of the Al-Mg intermetallic compounds(IMCs)at the interface zone of the AZ91D/A356 bimetal,while the Ni coating with the thickness of 45μm and 190μm can avoid the formation of the Al-Mg *** the Ni coating was 45μm,the Ni coating disappeared and transformed into Mg-Mg_(2)Ni eutectic structures+Ni_(2)Mg_(3)Al particles at the interface *** a thickness of 190μm’s Ni coating,part of the Ni coating remained and the interface layer was composed of the Mg-Mg_(2)Ni eutectic structures+Ni_(2)Mg_(3)Al particles,Mg_(2)Ni layer,Ni solid solution(SS)layer,Al_(3)Ni_(2) layer,Al_(3)Ni layer and sporadic Al_(3)Ni+Al-Al_(3)Ni eutectic structures from AZ91D side to A356 side in *** interface layer consisting of the Mg-Ni and Al-Ni IMCs obtained with the Ni coating had an obvious lower hardness than the Al-Mg *** shear strength of the AZ91D/A356 bimetal with a Ni coating of 45μm thickness enhanced 41.4%in comparison with that of the bimetal without Ni coating,and the fracture of the bimetal with 45μm’s Ni coating occurred between the Mg matrix and the interface layer with a mixture of brittle fracture and ductile fracture.

关键词： Magnesium/aluminum bimetal Microstructure Mechanical properties Ni coating Compound casting High velocity oxygen fuel spraying

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：