喷射成形Al11.4Zn2.6Mg1.7Cu合金沉积、预热和挤压3种状态的显微组织分析

利用金相、XRD、SEM、TEM等测试方法对喷射成形工艺制备的Al11.4Zn2.6Mg1.7Cu超高强铝合金材料沉积、预热和挤压3种不同状态的显微组织演变进行了分析。结果表明:沉积坯件和预热坯件的显微组织都由等轴晶粒组成,晶粒平均尺寸分别约为23和24μm,没有发生明显变化,经过热挤压后,晶粒沿挤压方向拉长;合金在沉积、预热、挤压3种不同状态,一次析出相主要组成为MgZn2,Al2Cu和Al2CuMg相,没有发生变化。沉积坯件晶内呈针状、类球状和块状等形态的MgZn2相经过热挤压之后在一定程度上被破碎,尺寸变小,弥散分布于晶内;原来存在晶界上的尺寸稍大的Al2CuMg相经过热挤压之后被剧烈破碎,由在沉积态中主要呈现的骨骼状变为尺寸细小的不规则形态,并沿挤压方向分布;Al11.4Zn2.6Mg1.7Cu超高强铝合金中添加的主要合金元素在沉积、预热、挤压3种状态中的分布规律没有发生变化。     

7B04铝合金预拉伸厚板的微观组织与性能

研究了7B04铝合金材料在不同热处理状态下的微观组织和性能。结果表明,目前的单级固溶处理（470℃×80min）并未使合金内一次析出相充分回溶,经物相分析确定残留相为MgZn2,S（Al2CuMg）,T（Mg32（Al,Zn）49）及Al7Cu2Fe相等。T6状态下晶内析出相为细小GP区和η′相,晶界析出相为半连续状态,无明显的晶间无析出带（PFZ）存在,合金的抗拉强度达595MPa,电导率为31.7%IACS;在T7（115℃×7h＋160℃×12h）状态下,晶内的析出相为GP区、η′和η相,尺寸约为5～20nm,晶界有不连续的较为粗大相析出,有明显的PFZ存在,此时抗拉强度为532MPa,电导率为37.0%IACS;采用RRA处理可使合金获得较高强度和较高电导率,抗拉强度和电导率分别为575MPa和36.3%IACS,此时晶内析出相为η′和η相,晶界析出物粗大呈完全不连续分布,有明显PFZ存在。     

喷射沉积AlZn11Mg2Cu1合金的固溶处理制度研究

对喷射沉积法制备的Al Zn11Mg2Cu1合金在465℃、485℃、500℃三种固溶温度下进行了合金组织和性能的研究。结果表明,试验合金适宜的固溶处理制度为485℃,保温1h,水淬。分析表明,喷射沉积制备的合金的晶粒度为4~5 m,晶粒比较均匀。用TEM对峰时效态的试验合金进行了微观组织分析,合金经固溶处理和时效处理后,沉淀相首先沿晶界析出,然后在晶内析出,其尺寸一般为5~10nm。     

Al?Zn?Mg?Cu?Zr?(Sc)合金搅拌摩擦焊接头组织和性能

利用光学显微镜、透射电子显微镜、显微硬度计和万能拉伸试验机等分析手段,表征了Al?Zn?Mg?Cu?Zr?(Sc)合金搅拌摩擦焊（FSW）接头的显微组织和性能,探究了Sc元素对改善超高强Al?Zn?Mg?Cu?Zr合金焊接性能的作用机制。结果表明:Al?Zn?Mg?Cu?Zr?(Sc)合金焊接接头具有相似的组织特征,焊核区为动态再结晶组织,由细小均匀的等轴晶组成,包含较高密度的位错线,大部分时效析出相回溶;热力影响区晶粒被拉长,位错密度更高,残留的时效析出相显著粗化;热影响区保留与母材相同的晶粒形态,大部分时效析出的η'相发生长大,少部分粗化成η相。添加质量分数0.17%的Sc,可以使合金FSW接头抗拉强度提升43 MPa,屈服强度提升23 MPa,断后伸长率改善2.3%,焊接系数达到74.1%。Al₃(Sc,Zr)二次析出相可以强烈抑制位错、亚晶界、晶界的移动,细化晶粒的同时保留大量的亚结构,且自身可发挥Orowan弥散强化作用。因此,可通过细晶强化、亚结构强化和弥散强化三种方式显著提高合金FSW接头的力学性能。      

喷射成形Al11.4Zn2.6Mg1.7Cu合金沉积态显微组织分析

利用喷射成形工艺制备了Al1 1 .4Zn2 .6Mg1 .7Cu超高强铝合金材料 ,用金相、SEM、TEM等测试方法对其显微组织进行了分析。研究结果表明 :沉积坯件主要由等轴晶粒构成 ,晶粒平均直径约为 2 3μm ,添加的合金元素Zn ,Mg和Cu呈有规律的分布 ,通过XRD和TEM分析 ,Al1 1 .4Zn2 .6Mg1 .7Cu铝合金沉积坯件中第二相主要包括六方结构的MgZn2 相、四方结构的Al2 Cu相和斜方晶格的Al2 CuMg相。     

7055铝合金的化学成分、物相组成及其性能特点

说明了7055合金中Zn、Cu、Mg、Si、Fe和Zr等元素在该合金中的作用或影响;阐述了该合金的物相组成和-αAl、η（MgZn2）、S（Al2CuMg）、T（Al2Zn3Mg2）以及Al3Zr的作用;讲解了基体沉淀相（MPt）、晶界沉淀相（GBP）和晶间无析出带宽度（PFZ）对该合金性能的影响,介绍了该合金的性能特点进而介绍了该合金晶界腐蚀、应力腐蚀和剥落腐蚀的产生机理。总结了该合金化学成分、物相组成与宏观性能的对应关系。     

热处理对超高强铝合金沉积坯微观组织的影响

以喷射沉积技术制备的Al-12Zn-2.4Mg-1.1Cu-0.20Zr-0.30Sc-0.30Ni合金沉积坯为研究对象,采用DSC、XRD、SEM和TEM等分析手段对沉积坯在不同温度下热处理后的微观组织演变进行了研究.结果表明:室温沉积坯基体中有大量η相粒子;在不同热处理制度下溶质元素会发生回溶或脱溶,从而影响合金组织与性能;在460℃/8h热处理时,依附于富Cu初始η相粒子形成了亚稳态T((Al,Zn)49Mg32)相,该相在490℃/8h热处理后消失;490℃/8h热处理时Al3(Sc,Zr)粒子从沉积坯二次析出,其"钉扎效应"与Cu回溶造成的"晶格畸变"是490℃/8h时沉积坯硬度达到最高值(192HV)的重要影响因素.     

粉末冶金法制备SiCp/Al-Cu-Mg复合材料的固溶时效行为

通过XRD、硬度和电导率测试对比了不同固溶温度下Al-Cu-Mg合金与SiCp/Al-Cu-Mg复合材料中的析出相。XRD分析表明,经T4处理后,未增强基体铝合金中析出相为Al2CuMg相和CuAl2相,而复合材料中的析出相为CuAl2相和Mg2Si相。由SiC颗粒提供的游离Si与基体中的Mg生成了Mg2Si相,从而提高基体合金中Cu/Mg含量比,进而影响Al2CuMg相的生成。     

2A12铝合金凝固过程析出相的热力学研究

基于JMatPro材料设计软件,详细研究了2A12铝合金国标成分范围内Cu和Mg对凝固析出相,特别是S-Al2CuMg此类均热处理难以消除的粗大脆性相的影响。在此基础上,对比研究了国产与进口2A12成分以及析出相的差异。结果表明:粗大脆性相S-Al2CuMg的析出量对Mg含量较敏感,1.8%(质量分数,下同)上限Mg含量相较于1.2%下限Mg含量,SAl2CuMg相析出量增加66.54%。国产2A12铝合金中检测到的Mg含量较进口的Mg含量高,粗大脆性相S-Al2CuMg析出量多23.63%。在保证合金性能的前提下,Mg含量取中下限有利于减少合金凝固过程中粗大脆性相S-Al2CuMg的析出。     

Cu含量对汽车车身板用Al-1.0Mg-1.0Si-0.6Mn合金显微组织的影响

采用金相、SEM/EDS、XRD等研究了Cu含量对汽车车身用Al-1.0Mg-1.0Si-0.6Mn(in wt.%)铝合金结晶相及合金板材晶粒的影响规律.结果表明:Al-1.0Mg-1.0Si-(0.1~0.7)Cu-0.6Mn合金中主要存在部分可溶的浅灰色不规则条块状Al8(FeMn)2Si和黑色条块状或骨骼状结晶相Mg2Si,及完全可溶的球状或椭球状主要含Al1.9CuMg4.1Si3.3多相共晶产物;随着Cu含量增加,铸态合金中主要含Al1.9CuMg4.1Si3.3的共晶产物数量逐渐增多,而Mg2Si和Al8(FeMn)2Si结晶相变化不明显;同时,固溶后合金板材的再结晶晶粒变得越来越细,尽管Cu含量对合金冷轧板的晶粒尺寸影响不明显.     

China's Major Non-ferrous Metals Imports & Exports

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Zinc Production by Province in 2014

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80% of Chinese Firms Purchasing Overseas Mines Ended up in the Red

<正>Minmetals Resources acquired the world’s largest copper mine under construction for USD5.85 billion.One after another,listed companies Jien Nickle,China Molybdenum and Chihong Zinc and Germanium raised money to get involved in overseas mining projects…SOEs and private enterprises are engaged in a frenzy of overseas mine purchasing.A reporter with Economic     

Copper Processing Profit Dropped Sharply,Copper Consumption Will Face Impact in the Second Half of the Year

正Judging from China’s copper consumption field,the biggest consumption unit is electric power,which accounts for 47%of total consumption;it is followed by light industry sector,including household electrical appliance,machinery,durable goods and hardware etc,which accounts for 22%of total consumption;followed by transportation field,     

Central Geological Prospecting Fund Newly Added 16.47 Million Tonnes of Bauxite in 2013

正In 2013,the Central Geological Prospecting Fund(CGPF)Project newly discovered 15 ore fields,including 3 large above ore fields,and 5medium sized ore fields.The reporter learned from the recently published"Annual Report of Central Geological Prospecting Fund Project(2013)"that,from 2006 to 2013 the CGPF     

Manufacturers of Copper Tube for Central Air Conditioner Use Face Mounting Pressure in the Final Quarter of the Year

正This year,the investment growth rate of real estate industry continued to slow down,sold area of commercial housing also dropped significantly,which brought huge pressure to the domestic air conditioning manufactures.In the first half of the year,by relying on high growth in national financial expenditure,along with investment in public infrastructure     

Xinjiang Ranks No.1 in Production of Primary Aluminum in China

正Kang Yi,Honorary Chairman of China Nonferrous Metals Industry Association,said recently at the Forum on Development of the Non-ferrous Metals Industry in Central and Western China held in Zhengzhou that,as more and more electrolytic aluminum factories in Xinjiang came into operation,the electrolytic aluminum output of Xinjiang had reached2,275,000 tons in the first 7 months this year,     

Shenhuo Coal Industry and Electricity Power Completed800,000 t/a Aluminum Project in Xinjiang

正"Xinjiang project has been completed according to schedule,but total completion and total start of production are two different concepts,after completion it still needs a gradual process of reaching production target."On the morning of November 3,Shenhuo Coal Industry and Electricity Power told investors the above statement on the investor interaction platform.     

Guangdong Metal Transaction Center has Become the Second Largest Precious Metal Transaction Platform Nationwide

正The reporter learned from Guangdong Province Precious Metal Transaction Center that in 2013the Center maintained healthy development momentum,and had become the second largest precious metal transaction platform in China in terms of market size;currently Guangdong is quickening steps of financial innovation for the Center,aiming to build a transaction center with international core competitiveness.     

Seven Rare Earth Projects Involving Close to 3 Billion Yuan Investment Landed In the HighTech Zone

正On May 22,Baotou Rare Earth Industry Cooperation Consultation MeetingProject Agreement-signing Ceremony was held in Ningbo,nearly 40 enterprises from Ningbo,Guangdong,Hunan,and Shanxi participated in project consultation.After multi-lateral communication,agreements were signed for a total of 7 rare earth projects successfully.