Co-Ti/SiC、Co-Ti/石墨体系的润湿性研究

设计了Co-73.3Ti（质量分数）高温钎料，并采用座滴法研究了Co-73．3Ti／SiC、Co-73．3Ti／石墨体系的润湿性以及保温时间对接触角的影响。结果表明，Co-73．3Ti／SiC体系中由于活性元素Ti的加入增加了Si和C在钎料中的溶解度，体系润湿性随保温时间的延长逐渐改善，直至钎料在SiC表面完全铺展。而由于石墨结构中存在于固液界面的外缘线前的孔洞阻止了钎料铺展，保温时间对Co-73．3Ti／石墨体系的接触角影响较小。微观形貌分析表明，Co-73．3Ti钎料与SiC和石墨的界面处都发生了元素的互扩散。     

粉末冶金技术2005年第1~6期总目次

文题期页·研究与开发·W-Mo-Ni-Fe重合金中金属间化合物相析出机制的研究1 3燃烧合成TiB2-Cu-Ni金属陶瓷二次热压行为研究1 12TiB2对TiC基金属陶瓷显微组织的影响1 18超音速雾化器的气体流场分布研究1 22MI M支持块的充模流动计算机模拟1 26镁基储氢复合材料放氢过程相转变速率研究1 32机械合金化Mg-LaNi5合金的研究3 163石墨/Ni+Ti体系润湿性研究3 168原位制备细晶Si3N4-Si2N2O复相陶瓷3 172模具用Ti(C,N)/Al2O3陶瓷材料的微观结构与力学性能4 243金属添加剂对SHS陶瓷内衬复合管微观结构与界面连接的影响4 248金属注射成形1…     

钛基固溶陶瓷的显微组织和力学性能研究

TiC和Ti(CN)基陶瓷大量应用在切割工具上,这些陶瓷心部由未溶解的TiC和Ti(CN)颗粒组成,边部由烧结过程中形成的固溶相组成.TiC和Ti(CN)基陶瓷的断裂韧性稍低于WC -Co陶瓷,主要是因为Ni在TiC和Ti(CN)中的润湿性很差,而且与界面大量复杂的显微组织有关.总体来说,Ti(N)-MeC-Ni系陶瓷中除了含有碳化物- Ni界面,还有心部与内边缘和边部与外边缘(碳化物)的界面.     

用Ni＋Ti粉坯热压反应烧结连接SiC

用Ni＋Ti粉坯作为焊料，采用热压反应烧结连接法连接SiC陶瓷，研究了焊接温度、保温时间、连接压力和压坯厚度对试样连接强度的影响规律。在本文所述试验范围内，确定的最佳工艺为：连接温度1100℃，保温时间20min，焊接压力12．7MPa，焊料压坯厚度0．3mm，所得连接件的相对抗弯强度为53％。微观结构和XRD物相分析表明：在Ni＋Ti粉坯与sic陶瓷接合界面处，发生了元素的互扩散和界面反应，在适当的工艺条件下，接头界面具有在NiTi、Ni3C、Ni16Ti6Si7混合物的基体中弥散分布TiC相的微观组织，借助于主要基体相NiTi的韧性和与母材SiC晶格匹配良好的TiC可以实现有效的界面结合。     

超低碳钢连铸过程中Ti和P对水口结瘤的影响

浇注含Ti超低碳钢时,浸入式水口内产生结瘤,严重影响生产效率,同时对产品质量造成危害。根据企业生产的经验,随着超低碳钢中Ti和P含量的增加,水口结瘤的问题越来越严重。通过深入分析实际生产过程的试样和实验室研究,阐明浇注超低碳钢时Ti和P对水口结瘤的影响。分析了含Ti含P的超低碳钢水口结瘤物的成分,结果表明结瘤物的主要成分是氧化铝(>90%),Ti含量较少(0.58%～3.58%)。采用脉冲分布解析原子发射光谱法(OES-PDA)测得氧化夹杂物的大小随Ti含量的增加而变小。采用液滴法测定了溶质Ti和P对钢液/Al2O3体系的润湿性影响,结果表明Ti和P使体系接触角和钢液表面张力降低,其中Ti能够降低体系的接触角只是在其具有反应湿润性的情况下。研究表明Ti和P对产生结瘤的作用有显著区别:只要形成的表层界面具有润湿性,Ti就可以降低Al2O3夹杂物的大小,而氧化铝夹杂物颗粒越小,越容易结瘤。为了不产生结瘤就必须控制好Al脱氧的时间和Ti的加入时间。P可以增加Fe-Ti-P三元体系的润湿性是因为P可以增加Ti的活度,降低钢液的粘度。与Ti相比,P对产生结瘤的影响较小。     

活性粉末Ni-Al与SiC陶瓷的界面润湿特性和润湿机理研究

采用座滴法研究了不同Al含量、不同温度和保温时间对Ni-Al/SiC体系界面润湿性的影响,通过SEM、XRD分析了Ni-Al/SiC体系的润湿机理.结果表明,Ni-Al系焊料与SiC陶瓷的润湿过程属化学润湿,在本研究的试验范围之内,随着Al含量增加、温度升高、保温时间延长,润湿角下降.由于界面反应产物Al4C3的生成导致的扩散层体积增大是Ni-Al/SiC体系润湿性得到改善的关键.     

氮化硅陶瓷与金属热等静压扩散连接的研究

本文对热等静压方法进行Si_3N_4与碳钢的扩散连接过程进行了研究。考查了温度、时间,压力、陶瓷密度及表面粗糙度以及加入一层或两层Ti、Zr、Mo、Cu、Ni和Ni-Mo等中间层对连接强度的影响。检测了陶瓷金属连接的界面产物。结果表明,温度、压力、时间分别为1060～1340℃,50～150 Mpa,1～5 h范围变化时,Si_3N_4/钢界面都能产生很好的结合,连接体的强度随陶瓷密度的增加而提高。由于Ti、Zr、Mo中间层与Si_3N_4的反应产物分别为TiN,ZrN,Mo_5Si_3等脆性相,断裂总发生在陶瓷/金属界面上。中间层为Ni-Mo时,连接体具有最佳强度。     

钛渣与焦炭界面性质的研究

为揭示钛渣粘结焦炭的实质,用测定接触角的方法研究了炉渣与石墨和TiN的润湿性,结果表明,钛渣(不论还原与否)和普通渣都能强烈润湿TiN,但都不润湿焦炭,钛渣润湿焦炭在于渣-焦界面处沉积有反应生成的Ti(CN)的作用。     

Cu-Ti合金中Ti含量对C/C复合材料润湿性能的影响

利用超高温接触角测量仪、光学显微镜、扫描电镜、X射线衍射仪研究Ti含量对Cu-Ti合金与C/C复合材料润湿性的影响。结果表明,随Ti含量增加,Cu-Ti合金对C/C的接触角逐渐降低。当Ti的质量分数为4.8%时,接触角降低到90°以下,Cu-Ti合金与C/C复合材料部分润湿;当Ti的质量分数为8%时接触角降为0°,Cu-Ti合金与C/C复合材料完全润湿。润湿界面形貌与Ti含量相关,当Ti含量为8%时,界面出现宽大的层状剪切裂纹;当Ti含量为12%时,界面致密无裂纹,Cu-Ti合金能较好地渗入C/C复合材料中的孔隙;当Ti含量为16%时,界面出现数量较多的细小裂纹,Cu-Ti合金熔体中的钛元素向界面扩散形成富钛层,并与C/C复合材料中的碳元素反应生成厚度为3~5μm的连续TiC层,该TiC层可改善合金对C/C复合材料的润湿性能。     

铝基复合金属粉末钎焊石墨的界面结构及性能

以Al、Ti复合金属粉末为活性钎料对高纯石墨进行连接,研究加热温度和保温时间对接头组织和性能的影响。采用SEM、EDS、XRD研究接头界面结构及相的组成,并对钎焊机理进行分析。结果表明:1 100℃钎焊10 min时接头与石墨结合紧密,强度达到12.96 MPa。微观结构研究和XRD相分析表明界面区域发生了化学反应,反应产物主要为TiC;焊接接头的界面结构为石墨/TiC+TiAl3+Ti-Al固溶体/石墨。     

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.     

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.