抑制剂形成元素对取向硅钢中夹杂物析出行为及热轧组织的影响

研究了铝、氮和锰、硫摩尔比对取向硅钢中夹杂物的析出行为及热轧组织的影响。结果表明,钢中的夹杂物是少量尺寸小于5μm的、以Al2O3为核心外包Mn S与Al N的复合物;钢中析出物主要为尺寸小于0.5μm的Mn S与Al N的复合抑制剂。其中氮铝摩尔比为0.9、锰硫摩尔比为15.7的取向硅钢中析出物数量最多,铸坯中数量为5 937个/mm3,热轧板坯中数量为7 024个/mm3;平均尺寸最小,铸坯中尺寸为0.17μm,热轧板坯中尺寸0.15μm,热轧后钢中析出物数量增加,并且热轧板坯边缘和中心组织都最均匀。     

含硫易切削钢夹杂物控制试验研究

通过高温试验研究了钙处理和镁处理对含硫易切削钢中夹杂物的控制效果。钙处理后钢中夹杂物为CaAl-O+(Ca,Mn)S复合夹杂物、(Ca,Mn)S以及Mn S夹杂物;镁处理后钢中夹杂物为Mg Al2O4+(Mg,Mn)S、Al2O3+Mn S复合夹杂物、(Mg,Mn)S以及Mn S夹杂物。钙处理和镁处理后钢中的复合夹杂物所占比例分别为0.67%和3.57%。镁处理后钢中Ⅱ类Mn S夹杂物明显减少,91.7%的夹杂物尺寸小于3μm,纺锤率达到72.5%,其对夹杂物的控制效果优于钙处理。     

钛对硅 锰脱氧FeNi42合金中夹杂物的影响

 通过热力学计算及试验分析,系统研究了不同含量的Ti对Si Mn脱氧FeNi42合金中夹杂物数量、组成、形貌和尺寸分布的影响,利用扫描电镜和图像分析仪对试样中的夹杂物进行了检测。结果表明,当合金中钛含量较低时,夹杂物的中心部分是析出温度较高的Al Ti Mn复合氧化物,向外依次是锰硅酸盐和少量的MnS。随着钛含量的增加,夹杂物中钛含量逐渐增多,而Mn、Si等元素的含量逐渐减小。Ti的加入使合金中夹杂物的数量增多,尺寸减小,且呈均匀弥散分布。     

夹杂物对低合金钢点蚀诱发敏感性的影响

为了进一步提高低合金钢的抗点蚀性能,采用Ti/Al脱氧及Ca处理工艺熔炼并轧制制备了试验钢。利用场发射扫描电镜及能谱仪(SEM-EDS)、电化学极化试验及浸蚀前、后夹杂物的原位观测,研究了不同脱氧工艺钢中夹杂物在模拟海水介质中诱导点蚀的行为。结果表明:与Al脱氧钢相比,Ti脱氧钢中形成了富含Ti Ox、数量更多、尺寸更细小的夹杂物,有利于Mn S的局部分散析出,降低其诱发点蚀的危害,采用Ti脱氧工艺有助于提高钢的抗点蚀性能;Mn S诱发点蚀的能力强于氧化物夹杂,点蚀优先在Mn S夹杂与基体的界面处及夹杂物曲率半径小的区域萌生;降低夹杂物的腐蚀活性应该以调控夹杂物的组成为基础,其次优化夹杂物的形貌(球形化),在微米级范围内,夹杂物尺寸对点蚀诱发的影响最小。     

国内外23CrNi3Mo钎具钢洁净度的差异

通过国内外23CrNi3Mo钎具钢的洁净度对比，找出在冶金环节上与国外钎具钢的差距，并对国外钎具钢中夹杂物的生成机理进行了理论热力学计算。结果表明，国外钎具钢的洁净度较高，易偏析元素砷、磷等含量远低于国内钎具钢；夹杂物的类型主要以单独的Mg Al O类夹杂物和Mg Al O外包裹MnS类夹杂物为主，夹杂物的尺寸主要为0～3 μm；纵截面上MnS夹杂物具有很明显的拉长现象，且具有很好的熔断效果，宽度为1 μm左右，纵横比为3～6。国内钎具钢中夹杂物主要为单独的Mg Al O类夹杂物和Mg Al O外包裹(Ca,Mn)S类夹杂物，尺寸以3～6 μm为主；纵截面上，单独的(Ca,Mn)S沿轧制方向几乎不变形。热力学计算表明，MnS类夹杂物的两次析出是导致Mg Al O类夹杂物的包裹率达到70%、复合类夹杂物尺寸较小的主要原因。     

微量La对于残余元素Cu的析出影响

利用光学显微镜、扫描电镜及能谱观察含铜Q235钢中夹杂物分布及元素析出行为,观察到铜可以在Mn S夹杂物上异质形核,与垂体型Mn S夹杂物相比,铜更易在球形Mn S上析出,其析出相为富铜相而非硫化亚铜或者硫化铜。添加60×10-6La可使Mn S夹杂物弥散分布,且细化夹杂物,减少15μm以上较大尺寸夹杂物,显著增加5μm以下夹杂物。La在本实验钢中优先形成氧化物而非硫化物,SEM观察结果与Factsage软件计算结果吻合。SEM观察发现添加痕量镧可以使含铜析出相的分布更分散,TEM观察发现Cu、La之间存在复合析出相,经热力学计算得出最易出现的析出相为Cu37La3相。     

酸溶铝对铸态取向硅钢中第二相粒子组成和形貌的影响

试验的铸态取向硅钢(/%:0.044~0.056C,3.12~3.32Si,0.08~0.11Mn,0.002~0.008S,0.0029~0.0291Als,0.0062~0.0109N)由30 kg高频真空感应炉熔炼。通过场发射扫描电子显微镜/能谱仪(FE-SEM/EDS)研究结果表明,0.0029%Als钢中氧化物主要为SiO₂,存在片状、棒状及近似球状的独立MnS,未发现含铝的氧化物或氮化物;0.0090%Als钢中出现以Al₂O₃为主的复合氧化夹杂物,存在MnS与AlN的复合析出物。钢中Als增加,复合析出物多呈簇状发展。氧化物容易成为MnS-AlN复合析出的核心,钢中Als含量越低,夹杂物中的MnS含量越高;作为核心的氧化物夹杂的尺寸越小,形成的复合夹杂物的形状越规则,尺寸也越小。热力学计算结果表明,钢中Als含量主要影响了钢中氧化物夹杂的组成和AlN的析出温度及析出量。     

脱氧工艺对硅钢连铸坯非金属夹杂物的影响研究

 研究了Al+FeSi以及FeSi两种不同脱氧工艺对硅钢铸坯中非金属夹杂物的影响。通过合理的试验设计并运用T［O］含量测定、金相分析、SEM及EDS等研究手段,对铸坯中的夹杂物进行了分析,研究表明Al+FeSi复合脱氧不仅比FeSi脱氧具有更强的脱氧能力,且能使铸坯中的夹杂物在尺寸和数量上有明显降低,夹杂物的特征也由Si O Al Mn Ti Fe系变性为以尺寸＜5 μm的Al2O3夹杂为核心、包覆Al Si S Mn Ca Ti Fe O系的复合夹杂。     

取向硅钢连铸坯中夹杂物和析出相的形貌特征

通过多角度分析取向电工钢铸坯中夹杂物和析出相的形貌特征,得到了铸坯中典型夹杂物主要由氮化物和硫化物的复合夹杂物、硫化物、少量Al2O3和TiN所组成。经金相法可以推断出,铸坯中二维夹杂物主要为不规则的复合夹杂物,尺寸为1～2μm。试样经过硝酸酒精侵蚀后的夹杂物和析出相可以清晰看出Al-Cu-Ti-Mn-N-S复合夹杂物的不规则形貌和尺寸为1～2μm。采用电解法可以无损地展现出三维夹杂物和析出相,氮化物和硫化物的复合夹杂物主要是由Al-Cu-Ti-Mn-N-S组成,呈现边部圆润和锯齿状的不规则形状及花瓣状。硫化物主要是Mn-Cu-Ti-S,呈现矩形和圆片状。同时还有少量的四边形Al2O3和多边形TiN。     

刀剪材料9Cr14Mo电渣锭尾夹杂物的分析

研究了刀剪材料9Cr14Mo电渣锭尾夹杂物类型、尺寸及含量.结果表明:电渣前及电渣后锭尾的夹杂物主要是含钛的复合夹杂物,电渣后锭尾有内生夹杂物的形成,导致复合夹杂物中Si、Mn、Cr含量升高,电渣后锭尾夹杂物含量升高,且夹杂物尺寸变大.电渣前钢中夹杂物含量为0.633 mg/kg,电渣后锭尾夹杂物含量为4.38 mg/kg.显微夹杂物的数量,电渣前为11.82个/mm2,电渣后锭尾为15.08个/mm2;提出了控制电渣后锭尾夹杂物含量的措施.     

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.