低Ca/P比溶液电沉积羟基磷灰石涂层

电沉积羟基磷灰石涂层具有工艺简单、过程易控制、适于在复杂表面制备厚度均匀涂层的特点.沉积液的Ca/P比直接影响涂层中的物相组成与涂层形貌.作者采用电沉积与后续热处理相结合的工艺,用低Ca/P比溶液在金属钛表面沉积羟基磷灰石(HA)涂层.利用X射线衍射仪、透射电镜和扫描电镜分析涂层中物相组成及后续热处理对涂层中物相和涂层形貌的影响.结果表明:随电压与温度的升高,涂层中羟基磷灰石含量增加;空气中500℃热处理后,涂层基本转化为羟基磷灰石,其Ca/P比约为1.61;热处理前,涂层由块状和条状物质组成;热处理后,涂层形貌并未改变,它由纳米颗粒的HA凝聚烧结而成.     

宽带钢镀覆的未来

评论宽带钢镀覆工艺的改进和发展,用使用量和不同的镀覆方法及不同材料的优缺点论述了各种镀层的现状。从材料成本高和需要保存的角度来说明赞成扩大使用电沉积工艺的理由,因为电沉积比热浸镀和粉末涂层能严格控制涂层厚度和提供较薄、较一致的薄膜。     

电沉积-水热合成法制备羟基磷灰石生物陶瓷涂层的研究进展

评述了电沉积-水热合成法制备羟基磷灰石生物陶瓷涂层的相形成机理、工艺进展和工艺特点,并对有关问题进行了探讨。     

等离子物理气相沉积热障涂层研究进展

等离子物理气相沉积技术可通过气相、液相与固相的共沉积,实现不同组织结构涂层沉积,在高性能热障涂层制备方面表现出了很好的应用前景。本文简要介绍了等离子物理气相沉积工艺特点,并从等离子物理气相沉积射流特性、喷涂工艺与涂层组织特点、涂层性能及沉积机理这几方面综述了近年来等离子物理气相沉积热障涂层的研究进展。     

冷喷涂技术及涂层处理工艺的研究进展

相比于热喷涂工艺,近年发展起来的冷喷涂具有明显的优势,冷喷涂工艺可以实现低温状态下的金属涂层沉积,这种工艺过程对粉末粒子结构几乎无热影响．而对粒子的加速效果很好,金属材料沉积过程中的氧化可以忽略。本文介绍了冷喷涂技术的原理和特点,总结了冷喷涂技术在涂层沉积机制、工艺参数和涂层后期热处理三方面的最新研究进展。涂层与基体的界面结合以及涂层之间的粒子结合都是以机械结合为主．由此导致涂层与基体的结合强度不高。如何对冷喷涂涂层进行热处理,使其结合强度有所提高,已成为冷喷涂技术研究的一个新方向。     

新型航空发动机用 Ni-cBN 主动切削涂层切削性能研究

篦齿封严是航空发动机中的一种封严结构,为避免篦齿在服役过程中发生磨损,需在其表面制备防护涂层。国内多采用等离子喷涂氧化铝类耐磨涂层,但在苛刻工况下易剥落,防护性能欠佳。国际上近年出现一种采用复合电沉积工艺制备的新型主动切削涂层,性能更优。镍 - 立方氮化硼 ( Ni-cBN ) 是新型主动切削涂层中典型的一种。在 FGH95 基材试片和仿形模拟件上采用复合电沉积工艺制备了新型 Ni-cBN 主动切削涂层,研究了其在高温高速条件下与GH3536金属蜂窝的切削性能。结果表明,新型Ni-cBN涂层可在金属蜂窝上切割出形状规整的沟槽,对磨温升降低约 80 ℃,无过热灼烧迹象,热稳定处理后涂层仍保持切削能力,表现出优异的切削性能。     

涂层沉积过程对镍基高温合金和MCrAlY粘结涂层互扩散行为的影响

本文考察了不同镍基高温合金与两种化学成分的MCrAlY粘结涂层的互扩散行为。为明确涂层沉积过程对其影响,本文采用超音速火焰喷涂(HVOF)和低压等离子喷涂(LPPS)两种不同的喷涂工艺制备了MCrAlY粘结涂层。本文重点考察Kirkendall孔隙度的演变过程,其主要形成于基材与粘结层界面,并主要受涂层及基材化学成分的影响。实验研究表明:涂层沉积过程对Kirkendall孔隙度的演变过程具有较大影响。孔隙的形成可导致基材与涂层间粘结强度的降低,甚至引起涂层系统的功能性破坏。本文在涂层沉积后,将样品置于1050℃条件下进行最长可达2000小时的退火。为评估Kirkendall孔隙度,对样品进行微观组织和化学成分分析。结果表明:Kirkendall孔隙度的形成量以及形成位置很大程度上受涂层沉积过程的影响。一般而言,通过HVOF工艺制备粘结涂层的样品提高了元素扩散速率。由于在涂层沉积之前进行了表面处理,故造成上述现象的主要原因为基材材料的再结晶。     

离子束法涂硬铬

采用先进的离子束强化沉积法,可在各种材料中所选择的面积上涂上硬铬,该工艺可避免化学镀法所使用的溶液及由它所产生的毒性废料。铬涂层5～10μm,在受镀工件的表面直接被合金化,不需要铜或镍的过渡层。该涂层比传统的电镀铬要硬,因为涂层无氢,十分致密,且耐压。涂层也能重现基体表     

大直径钨管发热体等离子体喷涂成形制造技术

本文介绍了钨管发热体等离子喷涂成形制造技术,分析了钨管发热体成形沉积模具类型、喷涂工艺参数对成形管坯涂层密度、涂层热应力、涂层抗裂性的影响。确定了等离子喷涂成形制造大型钨管发热体的工艺参数,该方法是制取同类零件最有效的工艺方法之一。     

仿生预置晶种对钛基体表面电沉积制备羟基磷灰石涂层的影响

采用仿生预置晶种法在Ti基体表面构筑HAP晶种,为HAP涂层的形成提供核点,后通过电沉积在低温条件下获得HAP涂层。通过扫描电镜、X射线衍射和红外光谱以及拉曼光谱研究仿生预置晶种对电沉积制备HAP涂层的微观结构进行分析,并用MTT法进行细胞毒性测试。结果表明:随着仿生预置晶种时间从24 h延长至48 h,电沉积制备的HAP涂层表面形貌从三维网状结构向蜂窝状结构转变。相对于无预置晶种电沉积制备的HAP涂层,仿生预置晶种后电沉积得到的HAP涂层更为均匀致密,与基体结合强度更高,且更有利于成骨细胞的增殖、代谢和生长。     

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.