Si3N4用于生产HRB400Ⅲ级钢筋的试验研究

HRB400是钢铁产业政策中重点推广的高强度热轧钢筋.通过3种试验方案,系统研究了Si3N4合金作为增氮剂用于生产V微合金化Ⅲ级钢筋的可行性.结果表明,采用0.5 kg/t Si3N4合金和0.6 kg/t FeV合金完全可以达到甚至超过采用0.5 kg/t VN时的合理V、N配比,且钢筋性能优良稳定,是生产HRB400Ⅲ级钢筋的一种新合金化工艺.     

HRB400热轧带肋钢筋的微合金化研究

为提高热轧带肋钢筋HRB400的综合力学性能,试验了三种增氮剂Si3N4、VN和MnSiN的增氮效果,并将它们与FeV、FeNb、FeTi等合金配比进行微合金化研究。以钢筋的屈服强度、抗拉强度和延伸率作为力学性能的评价指标。研究结果表明:MnSiN的增氮效果最为明显,且它的使用可降低FeV、FeNb合金的消耗量,从而降低生产成本。采用MnSiN、FeV微合金化生产HRB400钢筋时,当MnSiN在钢中的加入量为5 kg/t时,FeV的适宜加入量为0.50 kg/t。     

新型高效强化合金用于生产HRB400E的研究

为了降低HRB400E螺纹钢筋的合金成本,采用了1种新型高效强化合金——微氮合金,在现有HRB400E螺纹钢筋加热轧制生产工艺的基础上,设计了3种试验方案,系统地研究了微氮合金结合FeV合金用于生产HRB400E抗震钢筋的可行性。结果表明:采用微氮合金和FeV合金,在加入量分别为0.60kg/t和0.85kg/t时,完全可以达到甚至超过采用加入0.55kg/t VN合金时钢材的力学性能。     

HRB400热轧带肋钢筋的性能分析

为了扩大经营品种，2002年3月韶钢用大电炉生产工艺试制与开发了HRB400Ⅲ级钢筋，本文重点对成品的性能和V微合金化的强化机理进行了分析，分析结果表明，试制的HRB400钢筋性能符合GB1499－1998标准要求，并同时满足二级抗震钢筋的性能要求，生产HRB400钢筋比生产HRB335钢筋可增加销售利润约90元／t。     

氮化硅铁用于生产HRB400的开发与应用

分析碳化硅铁用于生产含V HRB400 Ⅲ级钢的机理,生产的实践表明,常规轧制的HRB400 Ⅲ级钢,在保证力学性能不降低的条件下,添加氮化硅铁的V-N微合金化比单纯加入钒铁的V微合金化HRB400 Ⅲ级钢的钒铁加入量减少55%,经济效益明显.     

提高HRB400钢筋屈服强度命中率的研究

研究了碳、锰、硅、钒对HRB400钢筋屈服强度的影响.通过降低合金料加入量、提高转炉终点碳含量,实现化学成分的窄范围控制,提高了HRB400钢筋的屈服强度的命中率,同时降低了合金料吨钢消耗成本.HRB400钢筋适宜的化学成分控制范围是C0.21％ ～ 0.23％、Si0.4％ ～0.5％、Mn 1.32％～ 1.42％、V 0.034％～0.038％（HRB400B）和0.029％～0.033％（HRB400D）.     

微合金化HRB400高强度热轧钢筋的试制

HRB400高强度钢筋(％:0.19～0.25C、0.40～0.60Si、1.20～1.50Mn、≤0.040P、≤0.040S)由120 t转炉—钢包吹氩-120 mm×120 mm连铸工艺冶炼.为提高HRB400Φ12 ～22 mm热轧带肋钢筋的综合力学性能,冶炼时进行加5 kg/t钢MnSiN+0.4～0.9 k...     

高强度钢筋组织分析和强化工艺措施

Φ22~25 mm HRB400(/%:0.20~0.25C,0.25~0.43Si,0.90~1.15Mn)钢筋和Φ18~28 mm HRB500(/%:0.20~0.25C,0.50~0.65Si,1.38~1.53Mn,0.05~0.07V)高强度钢筋的生产工艺流程为100 t顶底复吹转炉-出钢脱氧合金化-钢包底吹氩气-160 mm×160 mm方坯连铸-连轧。通过对HRB400钢筋和HRB500高强度钢筋的组织观察,分析了V和Nb碳化物在钢中的析出行为及对性能的影响,提出了HRB400钢筋的表面淬火自回火组织层宜控制在1 mm以下和HRB500钢筋采用V-Nb复合微合金化强化改进措施。通过控制钢中C含量0.18%~0.23%,钢筋水冷后温度从650℃提高到700℃,HRB500钢筋采用V+Nb含量0.05%~0.07%复合强化等工艺措施。Φ22~25 mm HRB400钢筋屈服和抗拉强度分别从460~510 MPa和580~610 MPa下降至440~490MPa和570~620 MPa,Φ18~28 mm HRB500钢筋屈服和抗拉强度分别从560~610 MPa和670~700 MPa提高至570~620 MPa和680~710 MPa,显著提高了钢筋的综合力学性能。     

我国热轧钢筋的发展和现状

热轧钢筋是主要建筑用钢之一.我国同世界主要工业国家的钢筋应用水平相比还有较大差距.本文简要叙述了我国热轧钢筋半个多世纪的发展历程;阐述了三个主要级别HRB335、HRB400以及HRB500 钢筋的生产现状;指出了我国热轧钢筋在品种质量和工艺技术水平上有了长足进步.目前,我国处于推广应用HRB400Ⅲ级钢筋的重要时期,进一步优化HRB400生产工艺、提高钢筋性能质量具有重要的意义.     

HRB400热轧带肋钢筋新合金化工艺的研究

介绍了HRB400热轧带肋钢筋生产工艺流程,研究了强化合金+Fe V替代VN合金生产HRB400的可行性。结果表明,采用强化合金+Fe V的合金化工艺,完全可以达到采用VN合金化工艺的水平,钢筋力学性能稳定,是一种新的降低HRB400热轧钢筋成本的合金化工艺。     

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.