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Journal of Materials Science & Technology 2008年第1期24卷 131-135页

作者： Zhipeng GUO Shoumei XIONG Sang-Hyun Cho Jeong-Kil Choi Key Laboratory for Advanced Manufacturing by Materials Processing Technology Department of Mechanical Engineering Tsinghua University Beijing 100084 China Advanced Material R＆D Center Korean Institute of Industrial Technology 994-32 Dongchun-Dong Yonsu-Ku Inchon Korea

A method based on die casting experiments and mathematic modeling is presented for the determination of the heat flow density （HFD） and interfacial heat transfer coefficient （IHTC） during the high pressure die casting （HPDC） process.Experiments were carried out using step shape casting and a commercial magnesium alloy,am50.Temperature profiles were measured and recorded using thermocouples embedded inside the die. Based on these temperature readings,the HFD and IHTC were successfully determined and the calculation results show that the HFD and IHTC at the metal-die interface increases sharply right after the fast phase injection process until approaching their maximum values,after which their values decrease to a much lower level until the dies are opened.Different patterns of heat transfer behavior were found between the die and the casting at different thicknesses.The thinner the casting was,the more quickly the HFD and IHTC reached their steady states.Also,the values for both the HFD and IHTC values were different between die and casting at different thicknesses.

关键词：： Interfacial heat transfer coefficient High pressure die casting process am50 Magnesium alloy

Direct electroless Ni-P deposition on am50 magnesium alloy from sulfate bath

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中国有色金属学会会刊：英文版 2006年第A2期16卷 65-69页

作者：李光玉牛丽媛江中浩谷长栋连建设 Key Laboratory of Automobile Materials Ministry of Education College of Materials Science and Engineering Jilin University Changchun 130025 China

A bright electroless Ni-P deposition on am50 magnesium alloy in a sulfate plating bath was proposed by using direct plating process with non-chromate pretreatment. The electroless Ni-P plating on am50 magnesium alloy has an admirable appearance and good adhesion. The results indicate that the electroless Ni-P deposition with non-chromate pretreatment has better adhesion than that of zinc immersion coating. Anodic polarization curves indicate that the electroless Ni-P deposition obtained from the sulfate bath has similar corrosion-resistance to that obtained from basic nickel carbonate bath. The deposition process generates less pollutant by a non-chromate plating bath and is suitable for the magnesium alloys manufacture because of its low cost. The hardness of the electroless Ni-P plated am50 is about HV 720.6 and HV 969.7 after heat treatments at 180 degrees C for 2 h. The wear resistance of Ni-P plated magnesium alloy specimens is about 5 to 9 times as high as that of bare magnesium alloys.

关键词：硫酸盐电镀槽镁合金 am50 Ni-P沉积无电极直接沉积

Critical mechanical properties and FEA simulation for crashworthiness assessment of a coarse-grained cast am50 alloy

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Journal of Magnesium and Alloys 2015年第3期3卷 188-196页

作者： S.Xu C.H.M.Simha M.Gesing J.Liang J.Lo CanmetMATERIALS Natural Resources Canada183 Longwood Rd SHamiltonOntario L8P 0A5Canada

A coarse-grained am50 alloy was used as a model alloy for investigation of constitutive behaviour,Charpy toughness and effect of stress state on deformation and failure of cast Mg alloys.The results provide critical mechanical properties of a cast am50 alloy for crashworthiness assessment and development of finite element simulation techniques.For cast Mg alloys,the effect of strain rate and temperature is larger on tensile strength than on compressive strength because twinning is more extensive in compression than in tension.The effect of strain rate on compressive strength is negligible because twinning activity of the cast Mg alloy is dominant.The load vs.deflection of Charpy specimens were measured for modelling,and the effect of loading rate and temperature on load of Charpy specimens is very small because part of the specimen is in compression.The equivalent strain to fracture of the cylindrical round notched tension specimen decreases with increasing stress triaxiality;though for the flat-grooved plane strain specimen,the equivalent fracture strain remains constant over the range of stress triaxiality investigated.Because the two different specimen geometries give rise to different Lode angle values,the test results show that the Lode angle parameter is an important parameter for deformation and fracture of Mg alloys.Finite element simulations of loading of the cylindrical notched-tension and Charpy specimens were carried out using a Lode-angle dependent von Mises model,and were found to provide a reasonable description of the load-displacement curves measured in the tests.For the flat-grooved plane strain specimens,the computations under-predicted the force-displacement response measured.

关键词： Effect of strain rate and temperature Tensile and compressive Crash Simulation am50

Understanding of the influence of process parameters on the heat transfer behavior at the metal/die interface in high pressure die casting process

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Science China(Technological Sciences) 2009年第1期52卷 172-175页

作者： Allison John Research & Advanced Engineering Department Scientific Research Laboratory Ford Motor Company

The current paper focuses on the influence of the process parameters on the peak values of the inter-facial heat transfer coefficient (IHTC) at metal/die interface during high pressure die casting (HPDC) process. A "step shape" casting and am50 alloy were used during the experiment. The IHTC was de-termined by solving the inverse thermal problem based on the measured temperature inside the die. Results show that the initial die surface temperature (IDST, TDI) has a dominant influence while the casting pressure and fast shot velocity have a secondary influence on the IHTC peak values. By curve fitting, it was found that the IHTC peak value (hmax) changes as a function of the IDST in a manner of hmax =eαTγDI. Such relationship between the IHTC peak value and the IDST can also be found when the casting alloy is ADC12, indicating that this phenomenon is a common characteristic in the HPDC process.

关键词： high pressure die casting interfacial heat transfer coefficient am50 ADC12

am50-x(Zn,Y)镁合金的显微组织、力学性能与凝固行为

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金属学报 2016年第9期52卷 1115-1122页

作者：王峰马德志王志毛萍莉刘正沈阳工业大学材料科学与工程学院沈阳110870

将Zn和Y元素以原子比为6∶1的形式加入am50合金中,并采用金属型铸造成形,利用OM,SEM,EDS,XRD,热分析法及拉伸实验研究了am50-x(Zn,Y)(x=0,2,3,4,5,质量分数,%)合金的显微组织、凝固行为及力学性能.结果表明:向am50合金中按原子比为6∶1... 详细信息

将Zn和Y元素以原子比为6∶1的形式加入am50合金中,并采用金属型铸造成形,利用OM,SEM,EDS,XRD,热分析法及拉伸实验研究了am50-x(Zn,Y)(x=0,2,3,4,5,质量分数,%)合金的显微组织、凝固行为及力学性能.结果表明:向am50合金中按原子比为6∶1的形式加入Zn和Y元素后,组织得到明显细化,组织中并未形成Mg3Zn6Y准晶相,而是形成了颗粒状的Al6YMn6相和细小的Al2Y相,其中Al6YMn6相尺寸随着Zn和Y元素含量的增加而增大;当x≥3时,在组织中b相的周围逐渐形成层片状的F-Mg21(Zn,Al)17相,且其数量逐渐增加.热分析结果表明,F-Mg21(Zn,Al)17相约在354℃通过包晶反应形成,其中a-Mg和b相析出温度随着x的增加而降低.由于Al6YMn6相、Al2Y相和F-Mg21(Zn,Al)17相的形成,使得b相的尺寸减小、数量减少;当x=4时,合金组织最为细小,且合金力学性能达到最优,其抗拉强度、屈服强度和伸长率分别为206.63 MPa,92.50 MPa和10.04%.

关键词：镁合金 am50 显微组织热分析力学性能

Sb对am50-Y镁合金组织和力学性能的影响

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稀有金属材料与工程 2013年第1期42卷 99-103页

作者：刘子利周桂斌刘希琴朱晓春李健南京航空航天大学江苏南京210016 江苏中翼汽车新材料科技有限公司江苏常熟215542

研究合金元素Sb对am50-Y合金显微组织和力学性能的影响。结果表明,加入Sb后,合金晶粒明显细化,同时形成弥散分布的YSb相。YSb相作为异质形核核心,促进了细小弥散分布的Al2Y颗粒相的形成。随着Sb含量的增加,合金室温和150℃高温抗拉强度... 详细信息

研究合金元素Sb对am50-Y合金显微组织和力学性能的影响。结果表明,加入Sb后,合金晶粒明显细化,同时形成弥散分布的YSb相。YSb相作为异质形核核心,促进了细小弥散分布的Al2Y颗粒相的形成。随着Sb含量的增加,合金室温和150℃高温抗拉强度、延伸率及室温冲击韧性先上升后下降。当Sb含量为0.6%时,合金综合力学性能最好:合金室温抗拉强度、延伸率和冲击韧性分别为257MPa、9.9%和26J·cm-2,与未添加Sb合金相比分别提高了13.7%、15.9%和14.9%;合金的高温抗拉强度和延伸率达到203MPa和11.9%,分别提高了12.8%和15.5%。

关键词： am50 Y Sb 显微组织力学性能

铸态与挤压态am50-4%(Zn,Y)合金组织及力学性能

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材料导报 2020年第20期34卷 20076-20080页

作者：王柏宁王峰王志周乐毛萍丽刘正沈阳工业大学材料科学与工程学院沈阳110870

在am50合金中加入质量分数为4%的(Zn,Y)(Zn、Y原子比为6),通过OM、XRD、SEM/EDS、EBSD和拉伸试验研究了铸态am50、铸态及挤压态am50-4%(Zn,Y)合金的组织和力学性能。结果表明:将Zn、Y加入am50合金后,组织主要由α-Mg、β-Mg 17(Al,Zn)1... 详细信息

在am50合金中加入质量分数为4%的(Zn,Y)(Zn、Y原子比为6),通过OM、XRD、SEM/EDS、EBSD和拉伸试验研究了铸态am50、铸态及挤压态am50-4%(Zn,Y)合金的组织和力学性能。结果表明:将Zn、Y加入am50合金后,组织主要由α-Mg、β-Mg 17(Al,Zn)12和Φ-Mg 21(Zn,Al)17相以及少量Al 6YMn 6和Al 2Y相组成。添加Zn、Y元素使am50合金组织细化,β相的数量减少且形貌改善,铸态力学性能提高。在370℃对am50-4%(Zn,Y)合金进行热挤压变形后,固溶到基体中的β-Mg 17(Al,Zn)12相沿晶界析出,而Φ相并未析出。同时,少量的Al 6YMn 6和Al 2Y相仍弥散分布于合金基体中。此外,EBSD分析表明,挤压后晶粒细化至7.32μm,且呈现出典型的挤压织构。由于晶粒细化、沉淀强化以及挤压合金的典型织构,挤压态am50-4%(Zn,Y)合金的力学性能得到进一步提高,其抗拉强度、屈服强度和伸长率分别达到303 MPa、193 MPa和13%。

关键词：镁合金 am50 挤压变形微观组织力学性能

合金材料以及工艺参数对压铸过程中铸件／铸型界面换热系数的影响

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金属学报 2008年第4期44卷 433-439页

作者：郭志鹏熊守美曹尚铉崔正吉清华大学机械工程系先进成形制造教育部重点实验室北京100084 韩国生产技术研究院新材料研究开发中心韩国仁川

采用铝合金ADC12以及镁合金am50为铸件材料,并采用"阶梯"铸件进行了压铸实验.以压铸过程实际测得的温度作为输入参数,利用自行编制的热传导反算程序计算了压铸过程铸件/铸型间的换热系数.结果表明:不同合金材料对界面换热系数的影响主... 详细信息

采用铝合金ADC12以及镁合金am50为铸件材料,并采用"阶梯"铸件进行了压铸实验.以压铸过程实际测得的温度作为输入参数,利用自行编制的热传导反算程序计算了压铸过程铸件/铸型间的换热系数.结果表明:不同合金材料对界面换热系数的影响主要表现在换热系数的数值以及保持较高数值所持续的时间上,而对换热系数曲线的形状影响不大;随着高速速度的增大,较薄"阶梯"与铸型之间的换热系数增大;对于较厚"阶梯",随着铸型初始温度的上升,换热系数不断减小.随着铸造压力的增大,最厚"阶梯"与铸型之间换热系数逐渐增大,但铸造压力只在镁合金am50实验条件下表现出了明显的影响规律.

关键词：界面换热系数压铸 ADCl2 am50 工艺参数

热处理及挤压比对am50镁合金组织和力学性能的影响

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铸造 2005年第11期54卷 1076-1078页

作者：于宝义乔日金时海芳包春玲宋鸿武刘正于海朋沈阳工业大学材料学院辽宁沈阳110023 辽宁工程技术大学辽宁阜新123000

研究了热处理以及不同挤压比对am50镁合金组织和力学性能的影响。结果表明:挤压变形可显著地细化镁合金晶粒并提高镁合金的力学性能,经过挤压前固溶处理后,网状的β-Mg17Al12相完全溶解,然后通过挤压过程中发生形变诱发析出第二相来强... 详细信息

研究了热处理以及不同挤压比对am50镁合金组织和力学性能的影响。结果表明:挤压变形可显著地细化镁合金晶粒并提高镁合金的力学性能,经过挤压前固溶处理后,网状的β-Mg17Al12相完全溶解,然后通过挤压过程中发生形变诱发析出第二相来强化合金,可获得良好的力学性能。

关键词： am50 挤压比热处理组织与性能

Si对am50力学性能和高温蠕变性能的影响

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材料研究学报 2004年第6期18卷 630-634页

作者：黄晓锋王渠东卢晨丁文江上海交通大学轻合金精密成型国家工程研究中心

在基体合金am50中分别加入Si和Ca,研究了Si和Ca对am50-xSi合金的微观组织、力学性能及蠕变性能的影响.结果表明:加入Si后,合金高温蠕变性能随Si量的增加而增加并超过了AS41的水平;在am50-xSi中加入微量Ca以后,合金中的Mg2Si相得到细化,... 详细信息

在基体合金am50中分别加入Si和Ca,研究了Si和Ca对am50-xSi合金的微观组织、力学性能及蠕变性能的影响.结果表明:加入Si后,合金高温蠕变性能随Si量的增加而增加并超过了AS41的水平;在am50-xSi中加入微量Ca以后,合金中的Mg2Si相得到细化,从汉字状转变成颗粒状,室温及150℃拉伸性能明显提高.

关键词：金属材料 am50 蠕变显微组织力学性能