合金钢中合金元素的存在形式

合金钢中可添加的合金元素种类很多,常用的有Si、Mn、Cr、Ni、Al、B、Mo、W、V、Ti、Nb、Cu、Co、等。它们都可以固溶在δ固溶体、奥氏体和铁素体中。Mn、Cr、W、Mo、V、Ti、Nb等还可以固溶在渗碳体中,其分子式用（Fe,M）3C表达。     

合金化对ZrMn2基Laves相贮氢合金相组成的影响

研究了Ni、V、Cr、Co、Fe、Cu和Ti等合金化元素取代ZrMn2 基Laves相贮氢合金的B侧或A侧对合金相组成的影响。结果表明 ,采用不同的元素对A侧或B侧进行部分取代 ,将引起ZrMn2 基合金相组成的变化。采用Ni取代Mn后 ,ZrMn2 合金的主相结构转变为C15型Laves相 ,表明Ni为C15相稳定元素。对Zr Mn Ni三元合金 ,V为C14相稳定元素 ,而Co、Fe、Cu则为C15相稳定元素。取代量较少时 ,Cr为C15相稳定元素 ,取代量增加时 ,C15相稳定作用减弱。Ti元素为C14相稳定元素 ,Ti对Zr的部分取代将导致合金主相结构转变为C14型Laves相。合金化元素对ZrMn2 合金的相组成的影响与元素的电子浓度和原子尺寸不同有关     

Cr-Mo-V系高铁制动盘用钢的热力学研究北大核心CSCD

采用Thermo-Calc热力学计算软件,对高铁制动盘用钢在400-1600℃存在的平衡析出相进行了热力学计算,并研究了合金元素对析出相和A3点温度的影响。结果表明,制动盘用钢中主要析出相为MX、MC、M23C6和M7C3,其中M为Cr、Fe、Mn、Mo、V等,X为C、N和空位Va。C、Mn、Cr、Ni元素会降低A3点温度,而Si、Mo、V能提高A3点温度。综合考虑,适当降低C、Mn、Ni和Cr的含量,提高V、Mo的含量,以增加MX、MC的含量和提高钢的A3点温度,从而提高制动盘用钢的力学性能。     

新型电磁搅拌用无磁钢

目前无磁辊的原设计材质是X5 NiCrTi26-15(西马克),属于德国牌号.国产牌号为GH2132,0 Cr15 Ni25 Ti2 MoAlVB.该成分的主要特点添加大量的稳定奥氏体化的元素Ni,来获得单相的奥氏体钢,使其具有低的磁导率. 本课题成分设计的目的是降低成本,同时获得要求的性能,如足够低的磁导率、较高的屈服强度和抗拉强度、合适的伸长率.要获得无磁钢,必须获得单相奥氏体.在此基础上,保证强度和合适的伸长率.稳定奥氏体的元素有Ni、Co、Mn、C、N等,不稳定奥氏体的元素有Ti、V、Mo、W、Cr、B、Nb等.非碳化物形成元素:Ni、Co、Al、Cu、Si、P、S等;碳化物形成元素有Ti、V、Cr、Mn、Fe、Nb、Mo、W等.在设计成分时,考虑用较便宜的奥氏体化元素如Mn、N等来降低或者替代Ni.当含Mn元素较高,奥氏体钢易发生形变诱导硬化,使其具有高的强度和韧性.另一方面,降低不稳定奥氏体化的元素,如Cr等.     

Cr-Mo-V系高铁制动盘用钢的热力学研究

采用Thermo-Calc热力学计算软件,对高铁制动盘用钢在400~1600℃存在的平衡析出相进行了热力学计算,并研究了合金元素对析出相和A3点温度的影响。结果表明,制动盘用钢中主要析出相为MX、MC、M23C6和M7C3,其中M为Cr、Fe、Mn、Mo、V等,X为C、N和空位Va。C、Mn、Cr、Ni元素会降低A3点温度,而Si、Mo、V能提高A3点温度。综合考虑,适当降低C、Mn、Ni和Cr的含量,提高V、Mo的含量,以增加MX、MC的含量和提高钢的A3点温度,从而提高制动盘用钢的力学性能。     

0Cr15Ni70Ti3AlNb合金平衡析出相热力学计算

采用Thermo-Calc热力学计算软件,模拟计算了0Cr15Ni70Ti3AlNb合金的平衡析出相和凝固过程。结果表明:0Cr15Ni70Ti3AlNb合金的平衡析出相主要包括γ、γ′、MC、M23C6;合金凝固过程中Ti和Nb属于正偏析,Cr、Fe、Si等属于负偏析。Al和Ti是影响0Cr15Ni70Ti3AlNb合金中γ′相析出温度和最大析出含量的主要因素。MC相的析出温度和最大析出含量主要由C元素决定。M23C6相的析出温度主要由Cr元素决定,M23C6相的析出量主要由C元素控制。0Cr15Ni70Ti3AlNb优化合金成分(质量分数)为C(0.03%~0.05%)-Al(0.7%~0.9%)-Ti(2%~2.25%)-Nb(0.75%~0.95%)-Cr(13.5%~15.5%)。研究结果可为合金的成分设计和热处理工艺制定提供理论指导。     

钢-铝轧制复合材料界面生成化合物的热力学计算及分析

通过分别添加Mn、Si、Zn、Ni四种合金元素进行界面调控,采用X射线衍射分析了钢-铝复合材料界面生成物相的类型,并对界面物相的生成进行了热力学计算和分析。结果表明:钢-铝复合材料界面生成的化合物主要是Fe2Al5,界面合金化处理不能改变钢-铝复合材料界面化合物的生成类型。但添加Si、Zn合金元素能在500℃扩散退火,保温1 h热处理工艺制度下,延缓Fe2Al5相生成时间,改善界面的结合。Mn、Ni合金元素对延缓界面化合物Fe2Al5相生成无益。     

微合金化对铝钢合金金属间化合物的第一性原理研究

材料的电子态密度对材料的导热及原子之间化学键连接具有重要的影响,文中采用基于密度泛函理论的第一性原理平面波赝势法,计算了合金元素(Cr,Mn,Mo,Ni,Ti,V和Zn)的掺杂对FeAl3电子特性的影响,以及Fel2Al39,(Fe10X2)Al39(X=Cr,Cu,Mg,Mn,Mo,Ni,Si,Ti,V,Zn)和Fe...     

热镀锌锅用钢的腐蚀机理分析及焊接对策的制定

探讨了热镀锌锅用钢中的C,Si元素含量对其腐蚀过程的影响.利用SEM对其在锌液中形成的腐蚀层进行组织形貌观察及相结构分析.结果表明,ξ相优先在Fe/Zn界面形成.随着钢中C,Si元素含量的增高,腐蚀层中Γ相消失,δ相区变薄,形成异常生长的ξ相,腐蚀速率加快.基于此,利用焊接材料中氧化性物质自氧化烧损C,Si元素的作用,研制了一种与08Cu热镀锌锅用钢相匹配的低碳、低硅焊接材料.焊缝化学成分取样分析结果表明,焊缝中的C,Si元素含量低于母材中的含量,使该焊接材料具有良好的耐锌液腐蚀性能.     

合金元素对钢在海水飞溅区腐蚀的影响

讨论了合金元素对钢在海水飞溅区腐蚀的影响。合金元素在青岛、厦门和榆林海域对钢在海水飞溅区的腐蚀有基本相同的影响效果。Mn、P、Si、Cr、Mo和Ni能减轻钢在飞溅区的腐蚀,其影响大小的顺序为：P＞Si＞Cr和Mo＞Ni和Mn;S、Al、V对钢的飞溅区腐蚀有害。Cu-P、Mn-Mo、Ni-Cr-Mo复合对减轻钢在飞溅区的腐蚀有好的效果。     

热浸镀锌合金技术的发展与应用

综述了国内外关于热浸镀锌合金技术的最新发展.研究表明,锌浴中同时加入Ni和Bi的热镀锌效果较常规锌浴及Zn-Ni合金浴更佳;锌浴中加入适量的Sn可抑制高含硅量(大于0.25%Si)的钢材镀层的异常生长,其抑制机理是由于Sn在Fe-Zn合金相层生长前沿会形成一层连续层,从而阻碍了Fe-Zn相层生长。文中还介绍了Zn-Sn-Ni-Bi、Zn-Sn-V(Ni)以及Al-Sn-Bi合金技术的实际应用情况.      

钢铁成分及添加元素对热镀锌组织和性能的影响

介绍了钢中元素(C、Si、P、Cu和Ti)对热镀锌组织和性能的影响。结果表明:通过向锌液中添加Al、Mg、Ni和微量稀土,合金的晶粒得到明显细化,组织得到改善,而且更加致密均匀,镀层厚度得到一定的减薄,从而提高了合金镀层的耐蚀性。     

非调质钢的合金设计与热加工工艺及性能

论述了非调质钢的性能特点，分析了V、Nb、Ti、Mn、Cr、Si等常用合金元素对非调质钢组织和力学性能的影响，并对热加工工艺、热处理等因素个性能的影响作了分析和讨论。     

合金元素对12SiMoVNb抗氢钢埋弧焊焊缝金属热裂纹敏感性的影响

本文用横向可变拘束裂纹试验法研究了合金元素对12SiMoVNb 钢埋弧焊焊缝金属热裂纹敏感性的影响,指出了Si、Nb、Ni 和Mo 提高焊缝金属热裂纹敏感性,Cr、W、V 等降低焊缝金属热裂纹敏感性.在试验基础上,提出了具有良好抗裂性的Cr-W 合金系统的焊丝,解决了该钢埋弧焊时的热裂纹问题.     

稀土元素在金属材料中的一些物理化学作用

针对不同金属溶液体系，采用了不同的实验方法，研究得到了铁液中Ｃｅ，Ｙ，Ｌａ，Ｎｄ，Ｓｍ分别与Ｓ，Ｏ，Ｓ＋Ｏ，Ｃ，Ｎ，Ｓｂ，Ｓｎ Ｐｂ，Ｐ，Ｃｕ，Ｔｉ，Ｎｂ，Ｖ溶质元素，镍液中Ｃｅ，Ｙ分别与Ｓ，Ｏ，Ｓ＋Ｏ溶质元素，铜液中Ｃｅ，Ｙ分别与Ｓ，Ｏ，Ｓ＋Ｏ，Ｓｎ，Ｚｎ，Ｐｂ，Ａｌ，Ｓｉ，Ｔｉ，Ｆｅ溶质元素，铝液中Ｃｅ分别与Ｍｇ，Ｔｉ，Ｍｎ，Ｚｎ，Ｆｅ，Ｓｎ，Ｐｂ，Ｎｉ，Ｃｕ，Ｓｉ，Ｓ溶质元素构成的６７个三元     

Effect of alloying element segregation on the work of adhesion of metallic coating on metallic substrate: Application to zinc coatings on steel substrates

A thermodynamic model based on the ‘Macroscopic Atom’ approach is proposed to assess the effect of alloying element segregation on the adhesion of metallic coating on metallic substrate. The interfaces that occur in hot-dip galvanized steels are considered, which include: Zn/Fe, Zn/Fe₂Al₅, Zn/FeZn₁₃, FeZn₁₃/Fe₂Al₅, and Fe₂Al₅/Fe. The effect of the alloying element on the work of adhesion of these interfaces is investigated, which includes Mg, Al, Si, P, Ti, V, Cr, Mn, Fe, Ni, Zn, Nb, Mo, Sn and Bi. Among these elements, Bi, Sn and Mg are predicted to decrease the work of adhesion of the Zn/Fe interface, whereas P, Nb, Mo, V, Ti and Ni tend to enhance this adhesion. The effect of element M (M = Al, Si, Cr, Mn) is positive when it exists in the zinc coating or negative when it occurs in the iron substrate. Among these interfaces, the Fe₂Al₅/Fe interface with a value of 3.8 J m⁻² is the strongest, whereas the Zn/FeZn₁₃ interface with of a value of 1.7 J m⁻² is the weakest. Delamination of the coating upon deformation is predicted to occur along the FeZn₁₃/Fe₂Al₅ and Zn/Fe₂Al₅ interfaces. This agrees with microscopic observations of hot dip galvanized steel after tensile testing.     

Microstructure of the coating and mechanical properties of galvanized chromium-rich martensitic steel

Protecting the modern high-strength steels against corrosion is a challenge because the coating technology must be compatible with forming and must preserve the mechanical performances. Batch galvanizing after hot stamping could provide a simple solution to this complex problem. A commercial high-strength martensitic steel containing 13 wt.% Cr, 0.35 wt.% Si, 0.3 wt.% Mn and 0.15 wt.% carbon has been galvanized with a commercial zinc alloy. Galvanizing produces a ~ 15 μm thick coating that is bright, continuous and metallurgically bonded. The intermetallic layer is made of ? crystals, which forms an open 3-dimensional structure. Tin, nickel and aluminium are found able to moderate the Sandelin effect. Comparison with other steels galvanized the same way indicates that chromium slows down the kinetics of the metallurgical reaction. Chromium distributes both in the ? and η phases, and follows a diffusion-like profile in the coating. The nickel from the alloy concentrates in the Fe-Zn intermetallic compound. Aluminium segregates at the surface and interface. It also provides a gettering effect that fixes silicon in sub-micron particles dispersed in the ? and η phases. Tensile experiments and fatigue tests demonstrate that the mechanical performances of the martensitic steel are preserved after coating. Comparison with similar experiments performed on a TRIP800 steel indicates that using galvanized martensitic steel is best worth in static applications.     

First principles study of site substitution of ternary elements in NiAl

Site substitution of ternary elements in ordered compounds influences the electronic structure and hence the properties of compounds at the continuous level. The electronic structure and binding energy of a number of NiAl-X alloy systems (X=Ti, V, Cr, Mn, Fe, Co, Zr, Nb, Mo, Hf, Ta, W, Si, Ga, or Ge) were calculated using the discrete variational cluster method based on the local density approximation of the density functional theory. The site preference of the ternary additions to NiAl was investigated by employing the Bragg–Williams model to analyse the calculated binding energy. The results show that all the considered ternary elements possess stronger preference to the Al sublattice sites than a Ni atom does. A new method of identifying sublattice substitution of ternary additions in NiAl was proposed by comparison of the binding energies per atom of the ternary and the binary clusters involving the fourth nearest neighbours. The analysis suggests that Fe and Co atoms occupy the Ni sublattice sites, whereas Si, Ga and Ti atoms occupy the Al sublattice sites. The remaining elements may substitute for both sublattices: Mn is most likely to go for the Ni sublattice; V, Cr, Zr, Nb, Mo, Hf, Ta, W and Ge have a larger preference for the Al sublattice, but Cr and W do not show significant preference to any sublattice. The densities of states involving alloying additions of Co, Si and Cr were further investigated to clarify the site preference of the alloying additions.     

Relationship between phase composition and corrosion resistanceof Ni-Ti-Nb based shape memory alloys

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