A356.2铸造铝合金铸锭内针孔缺陷的控制分析

为探索A356.2铸造铝合金铸锭的科学工艺方法,在阐述铸锭内针孔缺陷成因的基础上,对A356.2铸造缸盖铸件过程中铸锭内针孔缺陷进行了分析。通过加强缺陷检验和分析缺陷形成原因,提出从除气、过滤等角度加强针孔缺陷控制,改进铸件铸造工艺,能够提高铸锭内部质量,为相关铝合金材料生产提供参考。     

A356.2铝合金铸造工艺的生产实践

目前,A356.2铝合金主流的生产工艺有人工搅拌+链式铸造和电磁搅拌+热顶铸造两种方式,通过对上述产品的取样,对比分析了化学成分、组织结构和物理性能等,得出电磁搅拌+热顶铸造工艺生产的产品质量在各个方面均优于人工搅拌+链式铸造生产工艺产品质量,是生产高质量A356.2铝合金产品的发展方向。     

A356.2低压铸造铝合金车轮中Si偏析对产品质量的影响

A356.2低压铸造铝合金车轮通常会存在化学成分偏析的情况,通过对缺陷样件化学成分、金相组织等研究分析,发现存在偏析问题的样件化学成分、晶粒尺寸、产品外观样貌均存在异常。铸造铝合金车轮的成分偏析主要就是Si元素偏析,所以在铝合金车轮低压铸造过程中,合理的低压铸造工艺设计是解决其化学成分偏析、提高产品外观质量的最有效途径之一。     

提高A356.2铝合金方棒成品率的工艺措施

针对A356.2铝合金方棒生产成材率低的原因,分析了浇铸过程中对合金产品表面质量的影响因素,采用了在结晶器上改变水眼角度、在其上安装均压环和外装过滤网、对引锭头圆柱面进行加工处理及增加锥度等措施,有效改善了A356.2铝合金方棒表面质量,使其成品率提高了7.12%,降低了铸棒生产成本。     

汽车车轮用A356.2铝合金锭熔炼生产工艺研究

根据铝合金汽车车轮使用的A356.2铝合金的技术要求和合金特点,详细介绍了A356.2铝合金锭熔炼生产工艺中配料、成分、熔炼、炉内精炼、静置时间、浇铸温度、在线过滤和变质处理等控制方法。按此工艺控制后,产品质量合乎要求。     

两种不同铸造方式对5754铝合金铸锭质量的影响

从5754铝合金在铸造过程中容易出现拉裂缺陷的角度出发，分析了拉裂缺陷产生的主要原因，对比了普通模铸造方式和隔热膜铸造方式生产的5754合金铸锭的冶金质量，提出了两种铸造方式的差异，总结出合理的铸造工艺制度。     

Ce和Cu复合合金化对A356.2合金组织和力学性能的影响

利用光学显微镜、扫描电镜、X射线衍射仪、室温拉伸试验机等研究了Ce和Cu复合合金化对A356.2铝合金组织和力学性能的影响。结果表明，在单独添加Ce时，随着Ce含量的增加，A356.2铝合金中的α-Al相得到不同程度的细化，在添加0.1%的Ce时，合金中α-Al相的二次枝晶臂间距最小为29.6μm,其抗拉强度最佳，为310.8 MPa。因此选用0.1%Ce和不同含量的Cu来研究其对A356.2合金组织和力学性能的影响，随着Cu含量增加，A356.2合金中α-Al相得到细化，共晶Si得到有效的变质，并且出现新的Al₂Cu和Al₈Cu₄Ce相，起到固溶强化和弥散强化的作用，提高了合金的强度。在添加1.5%Cu和0.1%的Ce后，A356.2铝合金力学性能最好，抗拉强度为350.75 MPa,屈服强度为273.80 MPa,延伸率为6.52%。     

铝熔体精炼喷头的设计与应用

通过理论分析与生产实际结合,在A356.2合金锭的生产中,为了减少产品中的针孔,提高产品质量,采用了氮气加精炼剂复合精炼,在此基础上又重点设计制作了专用精炼专用喷头,大大增加了氮气和精炼剂与铝熔体的接触面积,铝合金熔体的含氢量显著降低,氮气和精炼剂的使用量也降低了20%左右。     

优化铝合金铸造工艺的策略研究

双金属复合材料是国家新材料发展规划的优先项目,铸造是金属由高温液态到固态的材料成型过程,铝合金铸件在工业领域应用广泛,国内铸造铝合金主要采用低压及重力铸造,低压铸造工艺因成品率高得到广泛应用,但低压铸造铝合金铸件存在缩孔缺陷影响使用寿命。铝合金铸件生产中产生各种缺陷,铸造铝合金在铸态时组织较差性能较低,Al-Cu系合金凝固温度区间较宽容易产生热裂纹,需要研究优化铝合金铸造工艺技术,有效提升铸造生产水平保证产品质量。     

Al-Sr(10%)合金变质剂试制及应用

用纯锶和工业纯铝试制生产了Al-Sr(10%)合金变质剂,加锶温度890℃,静置时间不超过3 min,铸造温度815~825℃,锶的吸收率达到80.02%,合金烧损仅为4.4%。对A356.2合金的变质应用表明,A356.2合金变质后的金相组织及力学性能均达到了市场产品同样的效果,完全满足用户要求。     

熔炼次数对M17返回料合金成分、组织和性能的影响

实验结果表明,M17铸造高温合金(%:0.16C、8.79Cr、5.79A1、4.93Ti、3.29Mo、15.20Co、0.78V、0.015B、0.073Zr、0.002S、0.001P、0.001 1O、0.001 0N)经25 kg真空感应炉返回重熔后,Si含量随重熔次数的增加而略有增加,合金中主要元素和其它杂质元素S、P、H的含量变化不大,而氧、氮略有增加;合金中初生碳化物由新合金中的草书体逐渐向返回合金块状转变,初生碳化物的遗传性堵塞合金凝固时的补缩通道,使返回料合金的疏松倾向增大,高温塑性下降较大。     

China's Major Non-ferrous Metals Imports & Exports

正~~     

Zinc Production by Province in 2014

正~~     

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.