共查询到19条相似文献,搜索用时 93 毫秒
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超洁净钢和零非金属夹杂钢 总被引:3,自引:0,他引:3
应针对不同钢种和用途 ,应用相应的精炼技术 ,达到超洁净钢对纯净度的要求 ,诸如超低硫钢要求 [S]≤ (5~ 10 )× 10 - 6 ,超低磷钢 [P]≤ 2 0× 10 - 6 ,低氮钢 [N]≤ 2 0× 10 - 6 ,显微夹杂钢要求钢中夹杂物尺寸≤2 0 μm等。零非金属夹杂钢为钢中夹杂物高度弥散、夹杂物尺寸≤ 1μm的钢。从理论上分析了零非金属夹杂钢制备的可能性。探讨了采用冷坩埚真空感应悬浮熔炼制备零夹杂钢的冶金工艺。采用中频感应炉熔炼 ,真空感应炉初精炼 ,真空凝壳炉或真空电子束熔炼深精炼可使超洁净钢中的Alsol<10× 10 - 6 ,[S]<10× 10 - 6 ,[T .O]<2× 10 - 6 ,[N]<15× 10 - 6 。 相似文献
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《冶金设备》2016,(1)
通过分析我国高铁用钢成分的标准制定以及与国外钢的成分标准的差别及我国对外招标购买国外重轨用钢的成分,发现我国重轨用钢对钢中有害元素的成分控制与世界先进水平差距甚远;分析研究了钢中五大有害元素[T.O]、[S]、[P]、[H]、[N]的含量及非金属夹杂物对钢的力学性能,特别是疲劳寿命的影响,其中重点研究了全氧含量对轴承钢疲劳寿命的影响;分析了目前冶金企业现有技术和设备的状况下冶炼高纯净钢的可能性,建议针对高铁轨道用钢有害元素含量制定更加严格的标准,特别是五大有害元素的含量:全氧含量[T.O]10×10-6;[S]10×10-6;[P]20×10-6;[H]1×10-6;[N]30×10-6;高速铁路轨道钢中五大有害元素[T.O]、[S]、[P]、[H]、[N]的总量应该小于71×10-6,即71ppm,以保障高速铁路运营时,不会因为轨道使用的钢材问题而出现恶性事故。 相似文献
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衡钢管线用洁净钢EBT EAF-LF(VD)-HCC工艺生产实践 总被引:1,自引:0,他引:1
衡阳钢管公司用 30tEBT电弧炉、LF(VD)和水平连铸工艺生产的管线钢洁净度为 :P≤ 0 .0 15 % ,S≤ 0 .0 0 6 % ,H 2× 10 - 6 ,N≤ 5 0× 10 - 6 ,O(15~ 30 )× 10 - 6 ,As+Sn +Pb +Sb +Bi≤ 0 .0 5 0 %。 相似文献
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以硅锰脱氧的SWRH82B热轧盘条为实验钢种,研究增氮析氮法对硅锰脱氧钢中夹杂物的去除效果,并设置0.02、0.035、0.05、0.065和0.08 MPa五组增氮压力进行热态实验.实验结果表明:在1873 K的温度下,钢液经过增氮20 min、真空处理30 min后,不同炉次钢中T[O]均下降至1×10-5以下,最低为4×10-6,T[N]均下降至5×10-6以下,最低为2×10-6,夹杂物去除率均为40%以上,T[O]去除率均大于78%,表明该技术对硅锰脱氧钢中的夹杂物及T[O]有良好的去除效果.此外,随着增氮压力的升高,钢中T[O]与夹杂物去除率均有所升高,当充氮压力为0.08 MPa时,T[O]与夹杂物去除率分别达到89.2%和87.4%.理论分析表明,随着增氮压力的升高,气泡形核率增大、钢中生成气泡数量增多、钢中气泡的密度增加,从而提升气泡去除夹杂物的效率. 相似文献
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在RH工艺精炼超低硫钢的热力学分析的基础上 ,用MoSi2 电阻炉进行了CaO Al2 O3 SiO2 MgO CaF2 渣系预熔渣和机混固体渣对钢液脱硫的试验 ,得出预熔渣脱硫速率较机混固体渣快 ,使用预熔渣时在 30min以内即可将钢中的硫含量从 116 7× 10 -6降低到 2 0× 10 -6以下 ,钢中最低终点硫含量可达 2 9× 10 -6。在30 0tRH装置上工业试验表明 ,使用预熔渣后 ,当RH精炼前钢中平均硫含量为 4 0 5× 10 -6时 ,RH精炼终点钢中平均硫含量降至 2 8 7× 10 -6,最低硫含量为 2 2× 10 -6,平均脱硫率为 2 8.9%。 相似文献
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因反应器在 32 0~ 5 5 0℃ ,14~ 2 2MPa和加氢条件下使用 ,炼油厂热壁加氢反应器筒体焊缝材料3Cr 1Mo 0 .2 5V ,2 .2 5Cr 1Mo V ,9Cr 1Mo等钢均要求高的纯净度 :P≤ 0 .0 0 3% ,S≤ 0 .0 0 3% ,H≤ 2× 10 - 6 ,O≤ 30×10 - 6 ,N≤ 80× 10 - 6 ,回火脆化敏感系数J =(Si+Mn) (P +Sn)× 10 4 ≤ 10 0 % ,X =(10P +5Sb +4Sn +As)× 10 - 2 ≤15× 10 - 6 。讨论了超纯净度焊材用钢生产工艺和研发的可行性。 相似文献
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氢在钢锭凝固过程中的运动及后果 总被引:1,自引:0,他引:1
通过对解剖坯的金相检验,找出了夹杂物在钢锭中的分布规律。采用相间能计算和重力流动分析得知,此分布规律是过量(H)钢锭凝固过程中的运动促成的。由此导出凝固过程中气泡一夹杂物-表面活性元素聚合体的运动模型,并从大量检验数据得到证实。 相似文献
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喂线技术与钢中铝含量的控制 总被引:1,自引:0,他引:1
傅余东 《金属材料与冶金工程》2002,(4):34-36
向钢包喂铝线脱氧,与出钢过程中向钢液中加铝块的技术相比,不仅铝的收率高,稳定,而且可降低钢中的氮含量,故提高了产品的质量和效益。 相似文献
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通过实测,了解平炉炼钢过程a_([o])的变化情况,将获得的数据归纳分析,得出了用以指导平炉脱氧合金化的结论。概述炼钢过程,从根本上来说是一个铁中杂质被氧化的过程。因此,氧的进入、消耗 相似文献
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"Our study is limited to the ballots distributed in the Spring of 1954: the presidential nomination ballot, the presidential election ballot, and a ballot proposing changes in the bylaws… . While a somewhat higher percentage of the Fellows vote than do Associates, nevertheless the Associates are so much more numerous that the great majority of the votes in each election came from this membership class." Approximately half of the respondents on each poll consisted of persons who had no divisional affiliation. Four tables are presented, one indicating the percentage of members of each division returning ballots and another indicating the percentage of voters belonging to each division. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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A space precipitation diagram of [Ce]-[O]-[S] in pure liquid iron has been constructed utilising recent experimental thermodynamic data gathered on allied equilibrium systems of RE-O, RE-S and RE-O-S. A quantitative correlation between the activities of oxygen, sulphur and the constitution of the formed RE inclusions has been found. This correlation was theoretically evaluated through thermodynamic calculation and verified by experimental data concerned with the activities of oxygen and sulphur in liquid iron and the composition of the formed RE inclusions. 相似文献
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E Costache CH Nguyen N Guilbaud S Léonce A Pierré G Atassi E Bisagni 《Canadian Metallurgical Quarterly》1998,13(4):373-386
Furo[3,2-e]- and pyrano[3,2-e]pyrido[4,3-b] indoles were synthesized from 1,4,5-trisubstituted 8-hydroxy-5H-pyrido[4,3-b]indoles. The intermediates, 10-chloro-6H-furo[3,2-e]pyrido[4,3-b]indole (11), 10-chloro-2,6-dihydro-1H-furo[3,2-e]pyrido-[4,3-b]indole (10) and 11-chloro-2,3-dihydro-3H,7H-pyrano[3,2-e]pyrido[4,3-b]indole (15), were substituted by diamines under thermal conditions (180 degrees C). In contrast, 11-chloro-3H,7H-pyrano[3,2-e]pyrido[4,3-b]indole (14), 9-allyl-1-chloro-4,5-dimethyl-5H-pyrido[4,3-b]indole (9a) and 8-propargyloxy-4,5-dimethyl-5H-pyrido[4,3-b]indole (8) led mainly to 1-aminosubstituted 8-hydroxy-5H-pyrido[4,3-b]indole derivatives resulting from an unexpected C3 unit elimination. When examined in three tumour cell lines (L1210 leukaemia, the B16 melanoma and the MCF7 breast adenocarcinoma) the new amino substituted furo[3,2-e]-, dihydrofuro[3,2-e]- and dihydropyrano[3,2-e]-pyrido[4,3-b]indole derivatives revealed cytotoxic properties, especially important for the 2,6-dihydro-1H-furo[3,2-e]pyrido[4,3-b]indole series. The most active compound (12b) significantly inhibits both DNA topoisomerases I and II, and is as potent as Adriamycin at inhibiting cell proliferation and inducing a massive accumulation of L1210 cells in the G2 + M phase of the cell cycle. However, 12b was less active than Adriamycin when tested in vivo against P388 leukaemia or the B16 melanoma tumour models. 相似文献