高强度汽车大梁钢800L组织和性能研究

采用低碳、铌钒钛微合金化成分设计及控轧控冷工艺在实验室进行了汽车大梁钢800L研制,研究了化学成分、加热保温温度和轧制及冷却工艺,进行了力学性能测试和显微组织分析.结果表明,试制的800L经1250℃保温后进行两阶段轧制,设定终轧温度860℃,轧后进行层流冷却,终冷温度600℃,得到力学性能优良的800L汽车大梁钢,其屈服强度、抗拉强度、断后伸长率分别为753 MPa、845 MPa、18.5％,180°弯曲试验合格.     

冷却工艺对Si-Mn系热轧双相钢组织和性能的影响

通过热轧试验研究了3种冷却工艺对传统成分Si-Mn系热轧双相钢组织及性能的影响。试验结果表明：在3种冷却工艺条件下,试验钢的最终组织为铁素体和马氏体双相组织。当终轧后采用空冷＋超快冷的冷却工艺时,钢板的屈强比最低,伸长率和n值最大,晶粒尺寸较大,但强度相对最小;当终轧后采用层流冷却＋空冷＋超快冷的冷却工艺时,钢板的晶粒...     

P510L钒微合金化钢的CCT曲线及其显微组织

通过测定P510L钢在不同冷速下的连续冷却转变的膨胀曲线,获得了该钢的CCT曲线;研究了P510L钢连续冷却过程中奥氏体的转变过程及转变产物的组织形态和显微组织;通过对CCT曲线的分析为控轧控冷工艺提供了理论依据。     

超高强铁素体/贝氏体双相钢的控轧控冷

通过实验室热轧机组的控轧控冷试验,研究了控轧控冷参数对超高强铁素体/贝氏体双相钢组织性能的影响。结果表明,采用不同温度终轧,轧后不同方式冷却,抗拉强度几乎都在1 000MPa以上,屈强比在0.54～0.62之间,伸长率在13%～17%之间。铁素体晶粒随终轧温度降低和冷却速度加快而细化;终冷温度降低,贝氏体量增多。经800℃终轧后层流冷却至560℃左右空冷,由于铁素体晶粒细化,组织中大量的粒状贝氏体、无碳化物贝氏体、少量的孪晶马氏体以及残余奥氏体的存在使抗拉强度达1 130MPa,伸长率达16%,强塑积达到18 080MPa.%的最高值。控轧控冷获得以铁素体/贝氏体双相组织为主并含有少量残余奥氏体+马氏体的复相组织,使试验钢具有了优异的力学性能。     

通钢FTSR工艺降低HP345屈强比的试验

为解决HP345焊瓶钢屈强比超标问题,在通钢FTSR生产线上,对影响屈强比的主要因素控轧控冷工艺进行试验研究。试验结果表明,提高终轧温度和卷取温度,层流冷却模式采取后段冷却,能够使HP345焊瓶钢的屈强比由最初的0.81降低至0.76,且各项力学性能满足国标GB 6653—2008要求。     

低屈强比汽车大梁钢的工艺研究与实践

为降低商用重型车架或底盘用钢510L材料的屈强比,对现有的低碳-锰-铌、低碳-锰-钛成分体系的屈强比进行了对比分析研究,确定采用低碳-锰-铌成分体系,并试验了该成分体系下不同冷却模式、不同卷取温度对屈强比的影响.结果表明,随着卷取温度的升高,屈服强度和抗拉强度均有大幅度下降,屈强比明显降低.层流采用后段冷却和两段冷却的...     

层冷工艺和卷取温度对700 MPa大梁钢组织性能的影响

对700 MPa级汽车大梁钢进行了热轧试验,采用光学显微镜、扫描电镜和能谱仪等设备研究了不同的层冷工艺和不同的卷取温度对试验钢组织和力学性能的影响.结果表明,在轧后不同的冷却工艺中,前段集中冷却模式所得到产品强度高于后段集中冷却模式所得到的产品强度,两段冷却模式所得到产品强度最优;在相同的冷却模式条件下,降低卷取温度,...     

超快冷+层流冷却工艺试制Q500q

研究了Q500q钢动态连续冷却转变规律,提出了采用超快冷+层流冷却工艺试制Q500q,试制工艺为第一阶段即粗轧开轧温度≥1 050℃,粗轧阶段累计压下率≥60%,待温厚度为2.5倍成品厚度;第二阶段即精轧开轧温度830～860℃,终轧温度780～810℃;采用超快冷+层流冷却联动方式进行冷却,终冷温度630～650℃,冷却速率在15℃/s。试验钢的金相显微组织由AF+B构成,晶粒度在13级左右,试验钢的屈服强度为538～560 MPa,抗拉强度为647～668 MPa,延伸率≥21%,-40℃低温冲击韧性≥160 J,Z向断面收缩率≥75%。试验钢板具有非常优异的强韧性配比,采用此工艺生产减少了传统工艺中的热处理的工序,降低了工序生产成本,而且试制的钢板仍然能满足国家相关标准的要求。     

控轧控冷对X60级管线钢显微组织及低温冲击韧性的影响

通过扫描电子显微镜、光学显微镜等对X60级管线钢显微组织与冲击试样断口形貌进行观察分析，研究了控轧控冷工艺对试验钢的热轧显微组织及低温冲击韧性的影响。结果表明：试验钢控轧控冷条件下冲击断口无明显裂纹源，基本呈现等轴韧窝形貌特征；其获得的针状铁素体组织较常规轧制下多边形铁素体组织更加细化、均匀，晶粒尺寸均值由20μm下降至8μm左右，其尺寸小于2μm的占比达75%以上；控轧控冷工艺较常规轧制试验钢具有更好的强度及塑韧性，尤其-10℃冲击功达到180 J以上。在生产过程中通过合理设定机架间冷却水强降温工艺与轧后层流冷却速率及卷取温度控制，实现精轧控制轧制与层流控制冷却相结合的控制工艺，可极大地改善超厚规格X60管线钢低温冲击性能。     

冷却模式对马口铁基板MRT-3组织性能的影响

在采用相同热轧温度工艺参数的前提下，对马口铁MRT-3热轧基料采用前段式冷却、两段式冷却、后段式冷却模式进行冷却并完成卷取，分析了不同冷却模式对马口铁热轧组织性能及冷轧生产过程的影响。结果表明，不同冷却工艺下MRT-3热轧板的金相组织均为多边形铁素体，但晶粒尺寸有所差别，采用超快冷-空冷-层流冷的两段式冷却模式的晶粒尺寸较大，平均16.5μm;无论是纵向取样还是横向取样，前段冷却模式下试样不同位置处的抗拉强度和屈服强度波动较大，且极差值较高，断后延伸率低；两段式冷却模式下试样的屈服强度、抗拉强度波动最小，且低于另两种模式，断后延伸率高；后段冷却模式下的力学性能介于两者之间。超快冷-空冷-层流冷的两段式冷却模式可促进铁素体晶粒长大，降低冷轧时的加工硬化，利于冷轧的稳定性。     

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.