Q.B. Yang
,
G.J Shifietand E.A. Starke
,
Jr(Department of Physics
,
Xiangtan University
,
Xiangtan 411105
,
China)(Depedment of Materials Science and Engineering
,
University of Virginia
,
Charlottesvil1e
,
VA22903
,
USA)
金属学报(英文版)
A clear understanding of the structure of the S precipitates which are present in Al-Li-X alloys is verp imporiant because the S -phase decreases the localization of strainand promotes less anisotropic properties during deformation. The close structural re-lationship between the S-phase and the Al matrix and their possible intedece bound-ary strvcture are described in detail. The proposed model is in good agreement with::::rimental obserwations. The dynamics Of the phase trunWrmation and possiblermation mechani8ms for the S,-phase are alSo proposed.
关键词:
Al-Li alloy
,
null
,
null
孙中强
,
车荫昌
,
姜茂发
,
梁连科
钢铁研究学报
为了确定钢液炉外精炼过程中加入钙使Al2O3夹杂物变性或与硫生成CaS的条件,通过热力学计算得出了1 600 ℃和1 550 ℃时Fe-Al-Ca-O-S系的平衡图.在CaO-Al2O3熔体组成,钢液中铝、硫和氧的活度以及钙的蒸气分压这5个变量中,只需知道其中两个变量,由此图就可直接查出与之平衡的其余3个变量.
关键词:
平衡图
,
夹杂物变性
,
脱硫
,
钢液
,
炉外精炼
Intermetallics
The sulfidation behavior of a 200 mum thick Fe-40at.%Al sheet has been investigated at temperatures between 973 K and 1273 K in H-2-H2S mixtures with H,S contents of 0.052-9.7vol%. The Fe-40Al sheet exhibited excellent sulfidation resistance at temperatures below 1073 K in all the H2S-H-2 mixtures. This may be attributed to the formation of a thin alumina film on the surface of the Fe-40Al sheet during sulfidation, identified by AES analysis. At temperatures higher than 1173 K, the Fe-40Al sheet also exhibited good sulfidation resistance in the 0.052%H2S-H-2, mixture. and there was only a slight increase in mass gain with tempe rat Lire. This compares favorably with Fe-200-11Al (in at.%) foil which was severely sulfidized even at 973 K in the 0.052% H2S-H-2 mixture, and showed markedly increased mass gain with increased H2S content and temperature. (C) 2004 Elsevier Ltd. All rights reserved.
关键词:
iron aluminides (based on FeAl);corrosion;fe-al alloys;corrosion behavior;oxidation behavior;iron aluminides;sulfur vapor;al2o3 scales;1273 k;atmospheres
包萨日娜
,
陈斌
,
姜敏
,
王灿国
,
王新华
钢铁
对超低氧钢中同时降低[Al]s、[O]的热力学以及实践方法进行了实验研究,并对实验结果和其它文献中结果进行了对比.结果表明,实验钢中T[O]和[Al]含量低而且波动范围窄、相对稳定,明显优于文献中的结果.从热力学角度分析,aAl2O3远小于1,即生成低熔点的易去除的复合夹杂物是同时降低[Al]s、[O]的关键.因此,同时降低[Al]s、[O]是可行的,并且实践中可通过生成低熔点的复合12CaO·7Al2O3夹杂物来达到同时降低[Al]s和[O]的目的.这一研究对解决连铸水口堵塞和提高钢材洁净度有着重要的意义.
关键词:
酸溶铝
,
超低氧含量
,
降低铝氧
包萨日娜
,
陈斌
,
姜敏
,
王灿国
,
王新华
钢铁
对超低氧钢中同时降低［Al］s、［O］的热力学以及实践方法进行了实验研究，并对实验结果和其它文献中结果进行了对比。结果表明，实验钢中T［O］和［Al］含量低而且波动范围窄、相对稳定，明显优于文献中的结果。从热力学角度分析，aAl2O3远小于1，即生成低熔点的易去除的复合夹杂物是同时降低［Al］s、［O］的关键。因此，同时降低［Al］s、［O］是可行的，并且实践中可通过生成低熔点的复合12CaO·7Al2O3夹杂物来达到同时降低［Al］s和［O］的目的。这一研究对解决连铸水口堵塞和提高钢材洁净度有着重要的意义。
关键词:
酸溶铝;超低氧含量;降低铝氧
Modelling and Simulation in Materials Science and Engineering
A first-principles investigation of the doping effects of S on the properties of a Ni/Ni(3)Al interface is conducted. S-doping is found to be energetically permissible either at sub-lattice sites or at octahedral interstitial centers, and S atoms prefer to substitute host atoms, especially Ni atoms, at the coherent (0 0 2)gamma/gamma' layer. Among octahedral interstitial centers, the most favorable condition is the S segregation onto an octahedral interstice bounded by 6 Ni atoms at the coherent interfacial layer. The calculation of Griffith rupture work Wand local bond overlap population shows that S-doping not only reduces the rupture strength of the Ni/Ni(3)Al interface, especially at preferentially occupied sites, but also causes the inter-phase fracture mode and site to be changed. Doping with the trace element sulfur is indeed deleterious for the strengthening of the Ni/Ni(3)Al interface; however, the segregation of S-doping onto the octahedral interstitial sites at the (0 0 1)gamma or the coherent (0 0 2)gamma/gamma' layer is demonstrated to be profitable for improvement of the local toughness of the Ni/Ni(3)Al interface to some extent, particularly in their inter-phase fracture regions. The S-induced embrittlement of the Ni/Ni(3)Al interface can be attributed to a variation in atomic bonding energy. As S replaces Ni at the (0 0 1)gamma layer or located at the octahedral interstices at the (0 0 1)gamma layer or the coherent (0 0 2)gamma/gamma' layer, the large local elastic strain energy in the inter-phase fracture regions should be responsible for the change in the inter-phase fracture sites.
关键词:
single-crystal superalloys;gamma/gamma' interface;electronic-structure;lattice misfit;1st-principles;embrittlement;sulfur;re;segregation;adhesion
董学泉
,
孔德军
,
王进春
材料热处理学报
利用电弧喷涂工艺在S355钢表面进行了喷涂Al涂层,通过SEM、EDS、XRD对试样表面-界面进行了形貌、物相、面扫描和线扫描分析.用能谱面扫描观察了涂层表面化学元素分布状态,并结合界面的能谱面扫描和线扫描分析,讨论了涂层与基体的结合机理.采用质量分数为3.5％ NaCl溶液进行了电化学性能测试,检验了Al涂层的耐腐蚀性能.结果表明,电弧喷涂Al涂层在S355基体表面形成均匀、致密、结合良好的Al涂层,其物相为纯Al和α-(AlFe),其中α-(AlFe)出现在扩散层;Al和O元素在涂层表面形成富集区,形成致密氧化膜对Al涂层进行保护;Al元素在结合界面形成富集层,其原子浓度发生阶梯过渡变化,在扩散层中发生Fe-Al化合反应,形成冶金结合方式;Al涂层极化曲线发生正向移动,耐腐蚀性较好,对S355钢基体起到了保护作用.
关键词:
S355钢
,
电弧喷涂Al涂层
,
表面-界面形貌
,
电化学腐蚀
薛攀龙
,
喇培清
,
刘辉
,
孟倩
,
魏玉鹏
钢铁研究学报
doi:10.13228/j.b0yuan.issn1001-0963.20140459
通过压力机和手动轧制机对WS-4非自耗真空电弧炉熔炼制备的Al的质量分数为0％、2％、4％的310S耐热钢在950～1250℃进行开坯轧制,研究不同Al含量的310S耐热钢热轧板材在800℃下的高温拉伸性能,用SEM观察拉伸断口.结果表明:不含Al和Al的质量分数为2％的合金,它们的高温抗拉强度均为210MPa左右,但当Al的质量分数增加到4％时,合金的热强性显著提高.3种合金拉伸断面均可以看到大小明显不同的显微韧窝,合金在断裂前经历了比较大的塑性变形,所以均为韧性沿晶断裂.随Al含量的增加,合金断口中的显微韧窝所占的比例随之增加.
关键词:
310S耐热钢
,
热轧
,
Al
,
高温力学性能
刘禹门
兵器材料科学与工程
doi:10.3969/j.issn.1004-244X.2005.05.001
为了研究含第二相的铝合金塑性变形的微观机制,用透射电子显微术研究了过时效Al-Cu-Mg合金在静载拉伸过程的塑性变形时位错与S相(Al2CuMg)沉淀物的相互作用.研究结果表明,在外加应力作用下,首先沉淀物与α-相基体间的相界释放出位错,同时,α-Al母体中的运动位错向着沉淀物运动,随后,这些运动位错在沉淀物前与沉淀物相界释放出的位错相互作用形成位错缠结,故此塑性变形过程可称为位错缠结机制.该研究结果说明,Al-Cu-Mg合金中S相的存在,对位错的运动和塑性变形有很大的阻碍作用,因而能明显增加材料的流变应力和加工硬化能力.
关键词:
铝合金
,
时效
,
塑性变形
,
位错
