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Temperature change and stress distribution analysis of die surface in Al-alloy die casting process and experimental study on die heat check 被引量:6
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作者 Hu Xinping Zhao Guoqun Wu Bingyao 《China Foundry》 SCIE CAS 2008年第1期47-53,共7页
The temperature change of the die surface in practical aluminum alloy die casting process was analyzed,and a 2D model was formulated on the basis of a deep concave round cavity without sliding core to analyze thestres... The temperature change of the die surface in practical aluminum alloy die casting process was analyzed,and a 2D model was formulated on the basis of a deep concave round cavity without sliding core to analyze thestress distributions along the die surface in detail. Equipment was designed to test the thermal state of the die steelin different thermal loading conditions. The results of stress analysis showed that, the value of thermal stress (maximum1.5 GPa) caused in the die filling and die spraying stages was larger than the mechanical stress (maximum 85 MPa)caused in the die locking stage. The results of the thermal check experiment showed that there were three stages ofdie dissolving, and that the stress distribution shown by the samples' cracking routine was close to the die surfacestress analysis. 展开更多
关键词 die temperature die stress die filling die locking die spraying die casting
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“三创五育”背景下“双一流”高校本科人才培养的DIE模式初探及评价
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作者 许章华 张超飞 +2 位作者 罗敏 杨远垚 刘智才 《高等理科教育》 2024年第2期53-61,共9页
针对新时代背景下“双一流”高校人才培养的发展需求,在“三创五育”理念指导下,解析基于产学研合作理论引入的DIE模式的内涵,系统阐述了DIE理念贯彻下的教学系统设计并付诸实践,旨在打破教学系、研究所、企业之间的壁垒,为学生学习、... 针对新时代背景下“双一流”高校人才培养的发展需求,在“三创五育”理念指导下,解析基于产学研合作理论引入的DIE模式的内涵,系统阐述了DIE理念贯彻下的教学系统设计并付诸实践,旨在打破教学系、研究所、企业之间的壁垒,为学生学习、实践提供更多样化的渠道。问卷调查结果表明DIE模式在本科生团队协作、学术创造、自信心树立等方面有切实作用,为培养全面发展的高素质本科人才提供了参考。 展开更多
关键词 “三创五育” die模式 “双一流”高校 本科人才培养
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基于DIES项目经验的中—德—东盟职业教育多边合作模式刍议
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作者 李小红 《广西教育学院学报》 2024年第4期17-27,共11页
德国DIES项目主要通过与亚洲、拉丁美洲和非洲等发展中国家的高校开展合作对话、成立联盟、能力建设和质量保障等举措,推动发展中国家的高等教育发展,促进文明互鉴、相互理解和跨国教育合作。当前,德国职业教育全球认可,国际推广布局整... 德国DIES项目主要通过与亚洲、拉丁美洲和非洲等发展中国家的高校开展合作对话、成立联盟、能力建设和质量保障等举措,推动发展中国家的高等教育发展,促进文明互鉴、相互理解和跨国教育合作。当前,德国职业教育全球认可,国际推广布局整体,战略引领路径有效;中国需要通过职业教育多边合作提升国际影响力;中—德、中国—东盟职业教育合作成效显著,模式成熟;中—德—东盟职业教育多边合作可行且必要。基于德国DIES项目的经验,建议整合中国、德国与东盟国家的优势,建立多边合作机制,推进数字化建设,创新中—德—东盟职业教育多边合作模式,促进中—德—东盟职业资格框架对接,密切中—德—东盟产业合作,从而促进三方职业教育与产业对接。 展开更多
关键词 dieS项目 中—德—东盟合作 职业教育多边合作 职业教育国际化
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Opportunities and challenges of Chinese die-casting market
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作者 Caifei SONG 《China Foundry》 SCIE CAS 2004年第1期23-27,共5页
The present status and perspectives of Chinese die-casting market were commented. In 2003, the total output of die castings in the whole country was 708000 tons, in which the outputs of Al-alloy, Zn-alloy, Mg-alloy, C... The present status and perspectives of Chinese die-casting market were commented. In 2003, the total output of die castings in the whole country was 708000 tons, in which the outputs of Al-alloy, Zn-alloy, Mg-alloy, Cu-alloy die castings were 474600 tons, 222000 tons, 5800 tons, 5600 tons, respectively, each accounted for 67%, 31.35%, 0.85%, 0.8% of the total. The annual sale volume of die-casting machines was approximately 1800. And the gross output value of dies approached RMB 38 billion, in which die-casting dies accounted for about 10%. In the die-casting industry of the entire country, the foreign capital enterprises, public-run enterprises, township and village enterprises, private enterprises accounted for over 80% of the total die-casting enterprises. Super huge die-casting groups are forming. 展开更多
关键词 die-casting market die-casting component die-casting equipment die-casting die die-casting alloys
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Approach Based on Response-Surface Method to Optimize Lining of Dies Used in 3D Free-Bending Forming Technology
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作者 Cheng Cheng Jiaxin Guo +2 位作者 Ali Abd El‑Aty Jie Tao Xunzhong Guo 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第5期307-331,共25页
In three-dimensional free-bending forming(3D-FBF),the tube is not overly constrained,and the plastic deformation behavior and forming quality of the bent tube are significantly affected by the critical structure of th... In three-dimensional free-bending forming(3D-FBF),the tube is not overly constrained,and the plastic deformation behavior and forming quality of the bent tube are significantly affected by the critical structure of the forming die lining.However,the effects of die-lining structural parameters on the tube quality,and a method to determine the combination of die-lining structural parameters is yet to be devised.This study aims to propose a new framework that allows one to understand the effects of various die-lining structural parameters on tube quality and to propose the best combination of die-lining structural parameters.First,finite-element modeling is performed to simulate 3D-FBF and examine the effects of individual die-lining structures on the quality of tube formation.The simulation results show that the deformation-zone length and die gap are positively correlated with the tube-section distortion and wall-thickness variation,whereas it shows an opposite trend with respect to the bending radius.Additionally,the lining chamfer radius of the bending die and the guide lining chamfer radius minimally affect the tube forming quality.Subsequently,the optimal die-lining structure is obtained using the response-surface method.The tube cross-sectional distortion rate reduced from 2.73 to 2.53%after the die lining is optimized.Additionally,the average inner-wall thickness reduced to 1.06 mm,whereas the average outer-wall thickness increased to 0.97 mm.This paper proposes a method for optimizing the forming-die-lining mechanism and for improving the tube forming quality in 3D-FBF. 展开更多
关键词 die lining Forming quality Response surface method Cross-sectional distortion Wall thickness
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Thin-walled and large-sized magnesium alloy die castings for passenger car cockpit:Application,materials,and manufacture
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作者 Lei Zhan Yu-meng Sun +6 位作者 Yang Song Chun-hua Kong Kai Ma Bai-xin Dong Hong-yu Yang Shi-li Shu Feng Qiu 《China Foundry》 SCIE EI CAS CSCD 2024年第5期525-545,共21页
In order to effectively reduce energy consumption and increase range mile,new energy vehicles represented by Tesla have greatly aroused the application of integrated magnesium(Mg)alloy die casting technology in automo... In order to effectively reduce energy consumption and increase range mile,new energy vehicles represented by Tesla have greatly aroused the application of integrated magnesium(Mg)alloy die casting technology in automobiles.Previously,the application of Mg alloys in automobiles,especially in automotive cockpit components,is quite extensive,while it has almost disappeared for a period of time due to its relatively high cost,causing a certain degree of information loss in the application technology of Mg alloy parts in automobiles.The rapid development of automotive technology has led to a higher requirement for the automotive components compared with those traditional one.Therefore,whatever the components themselves,or the Mg alloy materials and die casting process have to face an increasing challenge,needing to be upgraded.In addition,owing to its high integration characteristics,the application of Mg alloy die casting technology in large-sized and thin-walled automotive parts has inherent advantages and needs to be expanded urgently.Indeed,it necessitates exploring advance Mg alloys and new product structures and optimizing die casting processes.This article summarizes and analyzes the development status of thin-walled and large-sized die casting Mg alloy parts in passenger car cockpit and corresponding material selection methods,die casting processes as well as mold design techniques.Furthermore,this work will aid researchers in establishing a comprehensive understanding of the manufacture of thin-walled and large-sized die casting Mg alloy parts in automobile cockpit.It will also assist them in developing new Mg alloys with improved comprehensive performance and new processes to meet the high requirements for die casting automotive components. 展开更多
关键词 Mg alloys thin wall large size automotive part die casting
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Compression properties of cost-efficient porous expanded clay reinforced AA7075 syntactic foams fabricated by industrial-oriented die casting technology
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作者 İsmail Cem Akgün Çağın Bolat Ali Gökşenli 《China Foundry》 SCIE EI CAS CSCD 2024年第1期60-70,共11页
In today’s manufacturing industries,hard competition between rival firms makes it compulsory for researchers to design lighter and cheaper machine components due to the megatrends of cost-effectiveness and anti-pollu... In today’s manufacturing industries,hard competition between rival firms makes it compulsory for researchers to design lighter and cheaper machine components due to the megatrends of cost-effectiveness and anti-pollution.At this point,aluminum syntactic foams(ASFs)are new-generation engineering composites and come into the upfront as a problem-solver.Owing to their features like low density,sufficient elongation,and perfect energy absorption ability,these advanced foams have been considerably seductive for many industrial sectors nowadays.In this study,an industrial-oriented automatic die casting technology was used for the first time to manufacture the combination of AA7075/porous expanded clay(PEC).Micro evaluations(optical and FESEM)reveal that there is a homogenous particle distribution in the foam samples,and inspections are compatible with the other ASF studies.Additionally,T6 aging heat treatment was operated on one half of the produced foams to explore the probable impact of aging on the compressive responses.Attained results show that PEC particles can be an alternative to expensive hollow spheres used in the previous works.Besides,a favorable relationship is ascertained between the aging treatment and mechanical properties such as compression strength and plateau strength. 展开更多
关键词 die casting porous materials metal matrix sytanctic foams expanded clay compressive deformation
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Effect of slow shot speed on externally solidified crystal,porosity and tensile property in a newly developed high-pressure die-cast Al-Si alloy
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作者 Wen-ning Liu Wei Zhang +6 位作者 Peng-yue Wang Yi-xian Liu Xiang-yi Jiao Ao-xiang Wan Cheng-gang Wang Guo-dong Tong Shou-mei Xiong 《China Foundry》 SCIE EI CAS CSCD 2024年第1期11-19,共9页
The effect of slow shot speed on externally solidified crystal(ESC),porosity and tensile property in a newly developed high-pressure die-cast Al-Si alloy was investigated by optical microscopy(OM),scanning electron mi... The effect of slow shot speed on externally solidified crystal(ESC),porosity and tensile property in a newly developed high-pressure die-cast Al-Si alloy was investigated by optical microscopy(OM),scanning electron microscopy(SEM)and laboratory computed tomography(CT).Results showed that the newly developed AlSi9MnMoV alloy exhibited improved mechanical properties when compared to the AlSi10MnMg alloy.The AlSi9MnMoV alloy,which was designed with trace multicomponent additions,displays a notable grain refining effect in comparison to the AlSi10MnMg alloy.Refining elements Ti,Zr,V,Nb,B promote heterogeneous nucleation and reduce the grain size of primaryα-Al.At a lower slow shot speed,the large ESCs are easier to form and gather,developing into the dendrite net and net-shrinkage.With an increase in slow shot speed,the size and number of ESCs and porosities significantly reduce.In addition,the distribution of ESCs is more dispersed and the net-shrinkage disappears.The tensile property is greatly improved by adopting a higher slow shot speed.The ultimate tensile strength is enhanced from 260.31 MPa to 290.31 MPa(increased by 11.52%),and the elongation is enhanced from 3.72%to 6.34%(increased by 70.52%). 展开更多
关键词 hypoeutectic Al-Si alloy high pressure die casting POROSITY externally solidified crystal tensile property
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Characteristics and distribution of microstructures in high pressure die cast alloys with X-ray microtomography:A review
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作者 Hai-dong Zhao Xue-ling Wang +2 位作者 Qian Wan Wen-hui Bai Fei Liu 《China Foundry》 SCIE EI CAS CSCD 2024年第5期427-444,共18页
Al and Mg alloy high pressure die castings(HPDC)are increasingly used in automotive industries.The microstructures in the castings have decisive effect on the casting mechanical properties,in which the microstructure ... Al and Mg alloy high pressure die castings(HPDC)are increasingly used in automotive industries.The microstructures in the castings have decisive effect on the casting mechanical properties,in which the microstructure characteristics are fundamental for the investigation of the microstructure-property relation.During the past decade,the microstructure characteristics of HPDC Al and Mg alloys,especially micro-pores andα-Fe,have been investigated from two-dimensional(2D)to threedimensional with X-ray micro-computed tomography(μ-CT).This paper provides an overview of the current understanding regarding the 3D characteristics and formation mechanisms of microstructures in HPDC alloys,their spatial distributions,and the impact on mechanical properties.Additionally,it outlines future research directions for the formation and control of heterogeneous microstructures in HPDC alloys. 展开更多
关键词 high pressure die casting microstructure three-dimensional characteristics DISTRIBUTION Al and Mg alloys
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Survey of the 4th China International Diecasting Exhibition
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作者 Xianzeng PAN(Shenzhen MG Technology Co., Ltd., Shenzhen 518111, P. R. China) 《China Foundry》 SCIE CAS 2004年第2期147-151,共5页
Die casting machines, dies, die castings, peripheral equipments, die lubricants, raw materials for die casting, melting & holding furnaces, cleaning equipments, etc. were exhibited during the 4th China Internation... Die casting machines, dies, die castings, peripheral equipments, die lubricants, raw materials for die casting, melting & holding furnaces, cleaning equipments, etc. were exhibited during the 4th China International Die Casting Exhibition, which was surveyed in the paper. 展开更多
关键词 die casting machine die die casting peripheral equipment die lubricant raw material melting furnace cleaning equipment
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高中“Die”的用法小结
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作者 王新珍 《教育教学论坛》 2010年第1期99-100,共2页
die的各种形式及用法,die相关近义词组的辨析运用。
关键词 die DEAD DEATH die o屿die from die down与die away die off与die OUT
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Dietary approach in the treatment of nonalcoholic fatty liver disease 被引量:2
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作者 Silvia Marinho Ferolla Luciana Costa Silva +4 位作者 Maria de Lourdes Abreu Ferrari Aloísio Sales da Cunha Flaviano dos Santos Martins Cláudia Alves Couto Teresa Cristina Abreu Ferrari 《World Journal of Hepatology》 2015年第24期2522-2534,共13页
Nonalcoholic fatty liver disease(NAFLD) has been identified as one of the most prevalent chronic liver disease in adults and children populations. NAFLD is usually associated with the metabolic syndrome(MS), which is ... Nonalcoholic fatty liver disease(NAFLD) has been identified as one of the most prevalent chronic liver disease in adults and children populations. NAFLD is usually associated with the metabolic syndrome(MS), which is chiefly related to insulin resistance and its consequences. Insulin resistance has a crucial role in the pathogenesis of hepatic steatosis and potentially nonalcoholic steatohepatitis(NASH). Because of the contemporary epidemics of MS and obesity, the burden of NAFLD is also expected to rise. Unhealthy diets, such as the so-called western diet, are enriched in fructose, trans-fatty acids and saturated fat and seem to be associated with the development of NAFLD. In human studies, certain dietary sugars, particularly fructose, are used as a substrate for lipogenesis leading to hepatic fatty infiltration, inflammation, and possibly fibrosis. Other investigations have shown that fat consumption especially cholesterol and trans/saturated fatty acids are also steatogenic and seem to increase visceral adiposity. The identification of specific dietary components that favor the development of NASH could be important for the management of this disorder. This review focuses on the effects of different dietary approaches to prevent and treat NAFLD emphasizing the macronutrients and energy composition. 展开更多
关键词 Fatty liver dietary carbohydrates dietary fats die
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语义构建中的认知识解因素——以die of X和die from X为个案
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作者 戴志军 《黑河学院学报》 2023年第3期123-125,共3页
语义构建离不开认知识解因素。die of和die from可以与同样的表达式搭配,即die of X和die from X。就规约意义而言,die of X通常表达客观的、直接的原因,而die from X通常表达客观的、间接的原因。但在die of X和die from X语义构建过程... 语义构建离不开认知识解因素。die of和die from可以与同样的表达式搭配,即die of X和die from X。就规约意义而言,die of X通常表达客观的、直接的原因,而die from X通常表达客观的、间接的原因。但在die of X和die from X语义构建过程中,通过认知识解,客观的、直接的原因会被识解为主观的、间接原因,客观的、间接的原因会被构建为主观的、直接的原因。 展开更多
关键词 die of X die from X 语义构建 认知识解
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Determination of wax pattern die profile for investment casting of turbine blades 被引量:8
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作者 董一巍 卜昆 +1 位作者 窦杨青 张定华 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第2期378-387,共10页
In order to conform to dimensional tolerances, an efficient numerical method, displacement iterative compensation method, based on finite element methodology (FEM) was presented for the wax pattern die profile desig... In order to conform to dimensional tolerances, an efficient numerical method, displacement iterative compensation method, based on finite element methodology (FEM) was presented for the wax pattern die profile design of turbine blades. Casting shrinkages at different positions of the blade which was considered nonlinear thermo-mechanical casting deformations were calculated. Based on the displacement iterative compensation method proposed, the optimized wax pattern die profile can be established. For a A356 alloy blade, substantial reduction in dimensional and shape tolerances was achieved with the developed die shape optimization system. Numerical simulation result obtained by the proposed method shows a good agreement with the result measured experimentally. After four times iterations, compared with the CAD model of turbine blade, the total form error decreases to 0.001 978 mm from the orevious 0.515 815 mm. 展开更多
关键词 turbine blade numerical simulation displacement field wax pattern die profile investment casting
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Simulation of extrusion process of complicated aluminium profile and die trial 被引量:11
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作者 何钊 王赫男 +1 位作者 王孟君 李光耀 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第7期1732-1737,共6页
The arbitrary Lagrangian-Eulerian(ALE) adaptive remeshing technology and the HyperXtrude software of transient finite element simulations were used on analogue simulation of aluminium extrusion processing.The field ... The arbitrary Lagrangian-Eulerian(ALE) adaptive remeshing technology and the HyperXtrude software of transient finite element simulations were used on analogue simulation of aluminium extrusion processing.The field distributions of strain rate,stress,temperature and velocity of metal flow were obtained.The results are basically consistent with the experiment,which indicates that this method may successfully predict the defects in the actual extrusion process. 展开更多
关键词 transient finite element simulations complicated aluminium profile arbitrary Lagrangian-Eulerian(ALE) method die trial
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Low cycle fatigue behavior of T4-treated Al-Zn-Mg-Cu alloys prepared by squeeze casting and gravity die casting 被引量:6
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作者 郑成坤 张卫文 +1 位作者 张大童 李元元 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第11期3505-3514,共10页
Gravity die casting(GC) and squeeze casting(SC) T4-treated Al-7.0Zn-2.5Mg-2.1Cu alloys were employed to investigate the microstructures,mechanical properties and low cycle fatigue(LCF) behavior.The results show that m... Gravity die casting(GC) and squeeze casting(SC) T4-treated Al-7.0Zn-2.5Mg-2.1Cu alloys were employed to investigate the microstructures,mechanical properties and low cycle fatigue(LCF) behavior.The results show that mechanical properties of SC specimens are significantly better than those of GC specimens due to less cast defects and smaller secondary dendrite arm spacing(SDAS).Excellent fatigue properties are obtained for the SC alloy compared with the GC alloy.GC and SC alloys both exhibit cyclic stabilization at low total strain amplitudes(less than 0.4%) and cyclic hardening at higher total strain amplitudes.The degree of cyclic hardening of SC samples is greater than that of GC samples.Fatigue cracks of GC samples dominantly initiate from shrinkage porosities and are easy to propagate along them,while the crack initiation sites for SC samples are slip bands,eutectic phases and inclusions at or near the free surface. 展开更多
关键词 Al-Zn-Mg-Cu alloy squeeze casting gravity die casting microstructure mechanical properties low cycle fatigue
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Oxide distribution and microstructure in welding zones from porthole die extrusion 被引量:4
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作者 张新明 冯迪 +1 位作者 史兴宽 刘胜胆 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第3期765-772,共8页
The oxide distribution and microstructure in longitudinal and transverse welding zones during the billet-to-billet extrusion process through porthole die were adequately investigated by means of finite element method,... The oxide distribution and microstructure in longitudinal and transverse welding zones during the billet-to-billet extrusion process through porthole die were adequately investigated by means of finite element method,scanning electron microscopy and optical microscopy.The results indicate that the oxides exist at the interface between the matrix and transverse welding zone rather than longitudinal welding seam.The longitudinal welding zone reveals a darker band including the largest grain with irregular shape due to the abnormal grain growth under the heavy shear deformation and high temperature.The transverse welding zone consists of equiaxed recrystallized grains which are a little finer than those in the longitudinal welding seam. 展开更多
关键词 porthole die extrusion welding oxide distribution welding microstructure
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Extrusion force analysis of aluminum pipe fabricated by CASTEX using expansion combination die 被引量:2
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作者 曹富荣 温景林 +3 位作者 丁桦 王昭东 于传平 夏飞 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第11期3621-3631,共11页
To determine the extrusion force of pipe fabricated by continuous casting and extrusion (CASTEX) using an expansion combination die, the metallic expansion combination die was divided into diversion zone, expansion zo... To determine the extrusion force of pipe fabricated by continuous casting and extrusion (CASTEX) using an expansion combination die, the metallic expansion combination die was divided into diversion zone, expansion zone, flow dividing zone, welding chamber, and sizing zone, and the corresponding stress formulae in various zones were established using the slab method. The deformation zones of CASTEX groove were divided into liquid and semisolid zone, solid primary gripping zone, and solid gripping zone, and the formulae of pipe extrusion forces were established. Experiments were carried out on the self-designed CASTEX machine to obtain the aluminum pipe and measure its extrusion force using the expansion combination die. The experimental results of radial extrusion force for aluminum pipe are in good agreement with the calculated ones. 展开更多
关键词 continuous casting and extrusion continuous extrusion expansion combination die aluminum pipe stress analysis extrusion force
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Vacuum assisted high-pressure die casting of AZ91D magnesium alloy at different slow shot speeds 被引量:8
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作者 王青亮 熊守美 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第10期3051-3059,共9页
The effects of vacuum assistance on the microstructure and mechanical properties of high-pressure die cast AZ91 D alloy at different slow shot speeds were evaluated. Plate-shaped castings of AZ91 D alloy were carried ... The effects of vacuum assistance on the microstructure and mechanical properties of high-pressure die cast AZ91 D alloy at different slow shot speeds were evaluated. Plate-shaped castings of AZ91 D alloy were carried out on a TOYO BD-350V5 cold chamber die casting machine incorporated with a self-improved TOYO vacuum system. It was found that the vacuum pressure in the die cavity at the beginning of mold filling increases with the increase of slow shot speed, following a cubic polynomial curve, resulting in a decline in the porosity-reduction ability of vacuum assistance with the increase of slow shot speed. The externally solidified crystal(ESC) contents in conventional and vacuum die castings behave similar against the slow shot speed. The tensile properties of vacuum die castings were strongly influenced by the ESC content at relative low slow shot speeds. With the increase of slow shot speed, the influence of the gas porosity level in vacuum die castings would get prominent. 展开更多
关键词 vacuum die casting slow shot speed POROSITY externally solidified crystals
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Application of ultra-smooth composite diamond film coated WC-Co drawing dies under water-lubricating conditions 被引量:5
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作者 沈彬 孙方宏 +2 位作者 张志明 沈荷生 郭松寿 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第1期161-169,共9页
A specific revised HFCVD apparatus and a novel process combining HFCVD and polishing technique were presented to deposit the micro-and nano-crystalline multilayered ultra-smooth diamond(USCD) film on the interior-ho... A specific revised HFCVD apparatus and a novel process combining HFCVD and polishing technique were presented to deposit the micro-and nano-crystalline multilayered ultra-smooth diamond(USCD) film on the interior-hole surface of WC-Co drawing dies with aperture ranging from d1.0 mm to 60 mm.Characterization results indicate that the surface roughness values(Ra) in the entry zone,drawing zone and bearing zone of as-fabricated USCD coated drawing die were measured as low as 25.7,23.3 and 25.5 nm,respectively.Furthermore,the friction properties of USCD films were examined in both dry sliding and water-lubricating conditions,and the results show that the USCD film presents much superior friction properties.Its friction coefficients against ball-bearing steel,copper and silicon nitride balls(d4 mm),is always lower than that of microcrystalline diamond(MCD) or WC-Co sample,regardless of the lubricating condition.Meanwhile,it still presents competitive wear resistance with the MCD films.Finally,the working lifetime and performance of as-fabricated USCD coated drawing dies were examined under producing low-carbon steel pipes in dry-sliding and water-lubricating conditions.Under the water-lubricating drawing condition,its production significantly increases by about 20 times compared with the conventional WC-Co drawing dies. 展开更多
关键词 CVD diamond coated drawing die ultra-smooth composite diamond(USCD) film friction properties water-lubricating drawing dry sliding water lubrication
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