硼对780 MPa低碳贝氏体钢组织和力学性能的影响

试验低碳贝氏体钢（/%:0.08C,0.11~0.13Si,1.10~1.20Mn,0.008~0.009P,0.002S,0.21~0.23Ni,0.020~0.021Ti,0.003~0.004Nb,0~0.0010B,0.000 7~0.0008O,0.0031~0.0033N）由50kg真空感应炉熔炼,轧成45mm钢板,并经930℃淬火,610℃回火。研究了0.0010%硼对780 MPa低碳贝氏体钢45mm板组织和力学性能的影响。结果表明,硼可显著提高试验钢的淬透性,不含硼试验钢淬火后得到粒状贝氏体,0.0010%硼试验钢淬火后得到板条贝氏体。硼明显改善试验低碳贝氏体钢的力学性能,含0.0010%硼试验钢淬、回火后的抗拉强度834MPa和屈服强度771MPa远高于不含硼试验钢的抗拉强度702MPa和屈服强度591MPa,实际生产中应加入适量硼可使低碳贝氏体钢得到板条贝氏体。     

新型弹簧钢52CrMnBA淬透性试验研究

通过末端淬透性对比试验及模拟实物淬火试验,对新型弹簧钢52CrMnBA淬透性进行了试验研究.试验结果表明:52CrMnBA钢的淬透能力优于50CrVA,在830 ℃～870 ℃的淬火范围可均匀淬硬厚度不大于30 mm的弹簧扁钢.     

舵杆用Q345D钢热处理工艺对组织和性能的影响

试验研究了Q345D级钢(%:0.18C、0.41Si、1.34Mn、0.05Nb、0.08V、0.024A1)Φ280 mm锻材淬-回火处理和正火处理后的组织和性能。结果表明,经890℃空冷200 s,水冷+570℃回火后的钢抗拉强度R_m≥630MPa,屈服强度R_e≥455 MPa, -20℃冲击功A_KV 28～40 J;910℃空冷正火后R_m≥575 MPa, Re≥390 MPa, -20℃ A_KV42～59 J,均满足舵杆产品对力学性能的要求;淬-回火工件距表面30 mm的组织为回火索氏体+粒状贝氏体,中心组织为珠光体+少量粒状贝氏体,正火处理后工件表面与心部均为珠光体+铁素体组织。     

TMCP工艺生产40mm厚700MPa级低碳贝氏体钢试验研究

介绍了微合金化结合TMCP+回火工艺生产40 mm 700 MPa级低碳贝氏体钢的实验过程。通过对40 mm厚700 MPa级低碳贝氏体钢合理的成分、工艺设计和关键工艺控制的研究分析,制定合理的TMCP+回火工艺,成功开发出40 mm厚规格700 MPa级低碳贝氏体钢。     

添加微量元素Nb或V的低碳马氏体贝氏体钢

1　前言本文对 0 8Cr2 Mn2 V和 0 8Cr2 Mn2 Nb高强度钢进行了研究。对这些钢进行空淬可得到马氏体—贝氏体组织 ,其断面尺寸可达 3 0 0 mm厚 ,无论是热轧还是淬硬钢在零度以下都具有高强度 (σb>70 0 MPa)和高的冲击韧性 ,并把马氏体 -贝氏体复合组织性能与马氏体 贝氏体的组织性能进行了对比研究。热循环用于细化组织并提高马氏体 -贝氏体钢的机械性能 ,同时也建立了热循环状态下 TTT及超细晶粒奥氏体的动力转变曲线。为了得到表面硬化 ,采用了电子束处理技术 ,电子束处理确保淬透层深度 1 .8～ 1 .9mm,并提高了钢的显微硬度。2　低…     

40 mm规格700 MPa级别低碳贝氏体钢产品的开发

针对炉卷生产线和热处理回火处理线装备条件下,采用加入合金元素Mn、Mo、Cr、B,以提高钢的淬透性的方式来开发40mm厚度规格低碳贝氏体钢,经过几种不同成分的对比分析,采用Mn-B成分体系生产40mm低碳贝氏体钢是可行的.     

40mm规格700MPa级别低碳贝氏体钢产品的开发

针对炉卷生产线和热处理回火处理线装备条件下,采用加入合金元素Mn、Mo、Cr、B,以提高钢的淬透性的方式来开发40 mm厚度规格低碳贝氏体钢,经过几种不同成分的对比分析,采用Mn-B成分体系生产40 mm低碳贝氏体钢是可行的.     

0.25C-1.1Cr-0.7Mn-0.25Mo-0.05V高速动车车轴用钢的热塑性、组织和力学性能

0.25C-1.1Cr-0.7Mn-0.25Mo-0.05V钢经60 t EBT电弧炉-LF-VD-8.4 t铸锭流程冶炼。热模拟试样取自250 m/m×250 mm轧坯。通过Gleeble-3800热模拟试验机测试了温度(室温~1 200℃)对钢力学性能的影响,并得出0.1~35℃/s冷却速度下该钢的连续冷却转变曲线。并通过箱式电阻丝炉和盐浴炉测试了200 mm×200 mm坯经920℃正火,880~900℃油淬,630~680℃回火的力学性能。结果表明,该钢在900~1 200℃具有良好的热加工性能;当冷却速度大于15℃/s时可获得贝氏体+马氏体组织;采用920℃正火,880℃油淬,650~680℃回火后,该钢屈服强度R_(p0.2)为525~570 MPa,抗拉强度R_m为710~745 MPa,伸长率A为22%~23%,纵向冲击功(U-5mm)68~82 J,横向冲击功(U-5 mm)65~76 J,均符合标准要求。     

超高强韧油井管合金设计与高强韧机制

 为了揭示1 000 MPa级低碳加铌钒钛微合金钢的高强韧机制,研究了S1(w(C)=0.09%)与S2(w(C)=0.17%)两种合金成分的油井管钢成分-工艺-组织-性能关系。试验表明,两种成分试验钢经水淬后的组织分别为板条贝氏体加少量马氏体和马氏体加少量贝氏体的复相组织。两种成分钢经过450~600 ℃、30 min的中温回火后,组织中均出现碳化物析出,且S1试验钢回火后的屈服强度基本不变,抗拉强度下降了约70 MPa,S2试验钢回火后的屈服强度与抗拉强度迅速升高170 MPa左右。溶度积公式的计算结果表明,两种钢的水淬组织中铌、钛元素析出彻底且析出物的体积分数都很小,因此回火铁素体基体中的VC析出强化对S1试验钢回火后屈服强度保持不变以及S2试验钢回火后屈服、抗拉强度提高起到重要作用。     

淬、回火参数对250mm×250mm EA4T高速动车轴用钢组织和性能的影响

试验用250 mm×250 mm方坯EA4T车轴用钢(/%:0.23C,0.32Si,0.70Mn,0.014P,0.010S,0.18Mo,0.03V)的生产流程为60 t EBT EAF-LF-VD-8.4 t铸锭轧制-退火工艺。试验研究了880~920℃油淬、600~650℃回火工艺对该钢组织和力学性能的影响。经920 C+600℃、920℃+650℃和880℃+640℃淬-回火处理后,该钢的组织分别为马氏体、索氏体+马氏体和马氏体+贝氏体;880℃+640●℃淬-回火处理后EA4T钢的力学性能为R_(p0.2)525 MPa,R_m 720 MPa,A_5 23%,U-5 mm纵向冲击功68~82 J,横向冲击功65~86 J,其组织和力学性能均符合EN13261标准要求。     

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.