HRB400细晶粒热轧带肋钢筋的时效性能分析

通过对昆钢试验生产的HRB400细晶粒热轧带肋钢筋的自然时效和人工时效性能试验分析,得出昆钢生产的HRB400细晶粒钢筋时效后力学性能呈一定的规律性变化,主要表现为钢筋时效后屈服强度有一定下降,抗拉强度的变化不明显,伸长率平均升高了3个百分点,时效不影响钢筋的使用,并且自然时效后,钢筋的综合性能得到了提高.     

英标460级钢筋性能时效的研究

对采用轧后余热处理工艺生产的英标460级钢筋进行不同时间的自然时效后测定其力学性能。结果表明,自然时效后钢筋的屈服强度有较大幅度下降,抗拉强度有小幅度的上升。     

热轧带肋钢筋屈服不明显原因分析与探讨

针对涟钢热轧带肋钢筋的屈服不明显现象，从金属的金相组织、人工时效、自然时效、测试方法等方面着手，寻求各因素对钢筋力学性能的影响，并阐述了该异常组织的形成机理及相关因素，指出魏氏体、粒状贝氏体等的存在是造成带肋钢筋性能异常的主要原因，同时对部分屈服不明显的带肋钢筋判定提供了较为科学的依据。     

钒氮微合金化高强钢筋的研究与应用

对钒氮微合金化HRB400高强钢筋的自然时效性能、应变时效性能、韧脆转变温度、金相组织参数及V(CN)析出相进行了研究,结果表明VN微合金化HRB400钢筋具有良好的自然时效性能、应变时效性能,韧脆转变温度低于-20℃,适用于我国大部分地区的建筑,细小弥散分布的V(CN)析出物有益于钢筋强度、塑性的提高。大批量工业化生产实践表明VN微合金化HRB400钢筋产品性能优异、质量稳定可靠。     

HRB335带肋钢筋屈服不明显分析与探讨

本针对HRB335带肋钢筋的屈服不明显的现象，从金属的微观组织、人工时效、自然时效、测试方法等方面着手，寻求各因素对钢筋力学性能的影响，并阐述了该异常组织的形成机理及相关因素，指出魏氏体、马氏体、粒状贝氏体的存在是造成HRB335带肋钢筋性能异常的主要原因，同时对部分屈服不明显的带肋钢筋判定提供较为科学的依据。     

英标460MPa级钢筋余热处理工艺研究

以Q235、20MnSi钢坯为原料进行了用余热处理工艺生产英标460MPa级钢筋的试验,研究了水冷段数、水压、上冷床温度以及成分、钢种和时效对钢筋性能的影响。结果表明,Q235和20MnSi钢都可以利用余热处理工艺生产出性能合格的钢筋,但前者的生产成本较低;水压减小,钢筋强度降低,上冷床温度越高,强度越低,推荐5段水冷器全开,水压均为1.8～2.0MPa,Q235钢筋的上冷床温度应控制在650℃以下;钢筋典型的金相组织(Q235)表层为回火索氏体,过渡层为珠光体+铁素体且部分铁素体呈针状,心部为珠光体+铁素体,晶粒度8～10级;自然时效后屈服强度下降10～20MPa,用人工时效可以模拟自然时效,工艺是100℃×2h或200℃×1h。     

热轧带肋钢筋力学性能波动及时效试验

通过对安钢棒材机组生产的带肋钢筋性能进行自然时效试验,找出了热轧带肋钢筋力学性能指标值的波动特点,并提出了减小工厂检验与用户检验力学性能指标值的差异的方法。     

20MnSiV抗震钢筋的性能及钒的析出分析

对Φ28mm 钢筋进行了拉伸、焊接、应变时效以及夏氏冲击试验,并通过 TEM 对钢筋中 V 的析出物进行分析。结果表明:钢筋的强度较高,塑性有待于提高;焊接钢筋拉伸强度达到基体水平,弯曲试验焊缝没有出现裂纹;热轧态钢筋和应变时效钢筋低温韧性较好,韧脆转变温度较低;轧后冷却速度较快,冷却时间短,热轧钢筋中 V 的析出物较少。     

20MnSiⅡ级螺纹钢筋时效试验小结

对我公司生产的２０ＭｎＳｉⅡ级钢筋进行了时效试验，结果表明：我公司生产的２０ＭｎＳｉⅡ级螺纹钢筋，从取样当天时效到两个月，随时间延长，钢筋性能没有明显的变化。     

HRB400Ⅲ钢筋抗震性能研究

从强度与塑性的配合、应变时效敏感性、低温脆性、可焊性等方面对Ф20mm牌号为20MnSiV HRB400Ⅲ钢筋的抗震性能进行了系统的测试和研究。结果表明,钢筋应变时效后韧脆转变温度较高,低温抗震性能差;钢筋碳当量高,焊接性能有待改善;微观分析和成分分析结果表明,为加强钢筋的抗震性能,微合金元素应当适当调整。     

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.