高质量Mg-Zr中间合金的研制

以KCl、NaCl为熔剂，用液态Mg还原K2ZrR6,通过控制炉料配比、还原温度、还原时问，并用机械正反向交替搅拌，成功地解决了传统生产工艺中渣相与Mg-Zr中问合金难以分离、合金杂质含量偏高、合金成分偏析的难题，获得了高质量的Mg—Zr中间合金。     

稀土镁锆中间合金中锆的测定

采用EDTA滴定法测定了稀土镁锆中间合金中的锆.实验确定了合金分解方法及锆滴定时的酸度及温度条件,分析了基体及杂质铁的干扰及消除.分析结果相对标准偏差小于2.5%,标加回收率为98.9%～101.8%.     

铝热还原Sc2O3制备Al-Sc中间合金

采用铝热还原法进行了Al-Sc中间合金的制备。实验结果表明：在nNaF.AlF3-KCl-NaCl熔盐体系中,加入适量的ScF3,可以提高Sc2O3在熔盐体系中的溶解度;用液态铝还原Sc2O3制备Al-Sc中间合金,可以提高Al-Sc中间合金中Sc的含量（可达2%,质量分数）,并提高Sc的收率和中间合金的质量,降低生产成本,为Al-Sc中间合金的广泛应用创造有利条件。     

高锆镁锆中间合金工艺研究

应用N235-H2SO4分离技术，使锆与其他多种杂质元素分离，以提高原料K2ZrF6质量，降低合金杂质含量，通过控制炉料配比，稳定提高Zr的含量，采用机械搅拌替代传统的人工搅拌，加速生产过程还原反应进程，使合金成分均匀化，从而解决了合金成分偏析难题。     

新型真空热还原法制镁工艺分析

通过对真空条件下A l-S i-Fe合金还原白云石煅白的热力学分析及实验研究,得到真空条件下还原反应的吉布斯自由能及反应临界温度,确定工艺可行性;所进行还原实验的结果表明:在还原温度1 443 K、还原时间2 h、真空度4 Pa、制团压力50 MPa条件下,可获得86.4%的镁收率,相比同等条件下硅热法镁还原率仅为73.9%。     

新型镁稀土合金的研制和应用

本文叙述了稀土作为添加剂用以提升传统镁合金综合性能或特指单项性能的结果；介绍了稀土作为合金成分元素（含稀土与非稀土协同、轻稀土与重烯土组合）的耐热、抗高温蠕变、耐腐蚀等一系列新型镁稀土牌号合金；还例举了近期开发的稀土含量高达8-20%（重量）的先进镁合金。从这三方面显示出镁稀土合金前景广阔，需用稀土种类不少，数量相当多。为了迎接镁稀土合金快速增长期早日到来，介绍了开发该合金不可或缺的镁稀土中间合金的一项先进生产技术：“在较低温度下下沉阴极电解制取镁稀土中间合金工艺”，提供了比较理想的电解质熔体和电解条件，制得了镁-钇、镁-钕、镁-铈等二元中间合金以及更为便宜的镁-富钇、镁-富钕、镁-富铈、镁-富镧（即镧镨铈）等多元合金系列样品，其中稀土含量可调、合金成分分布均匀、杂质含量符合要求、生产成本低廉。经一汽、吉大等多个单位试用，效果满意。当前，面临的任务是尽快使这项新成果实现市场化、产业化；用事实排解国内外业内人士普遍存在着的“稀土加入镁合金虽然好，但是太贵，用不起和不易加入均匀等困惑”问题；促进新型镁稀土合金应用开发。     

铝镁热还原无水氯化钪熔盐制备铝镁钪中间合金工艺试验研究

进行了铝镁热还原无水氯化钪制备铝镁钪中间合金的研究,并且进行了铝镁钪中间合金小型试验;氩气搅拌试验及熔盐钟罩压入加氩气搅拌的铝镁钪中间合金试验.小型试验和扩大试验都取得了较好指标,基本确定了铝镁钪中间合金制备的工艺条件,已为半工业试验打下一定基础.     

以Si-Cu合金为还原剂的热还原制镁新方法及其热力学分析

结合Si-Fe相图,分析了硅铁热还原制镁(皮江法)反应过程中Si-Fe中形态,结果显示:初始含Si量75%的Si-Fe在1200℃基本处于固态,硅铁热还原制镁还原反应主要为固-固反应,反应过程中,物料间的热量及质量传输较困难,反应难于快速、彻底进行。介绍了采用Si-Cu合金还原剂实现固-液还原的Si-Cu热还原制镁新思路、新方法,结合Si-Cu相图,分析了Si-Cu热还原制镁中Si-Cu的形态,结果显示:Si-Cu热还原制镁时,初始含Si量低于35%的Si-Cu在1200℃几乎全过程保持液态,还原反应基本为固-液反应,反应较易快速、彻底进行。采用热力学分析方法,推演出了Si-Cu热还原制镁的主要反应式、吉布斯自由能估算式,临界反应温度估算式,分析了影响吉布斯自由能、临界反应温度及还原反应热力学可行性的因素,结果显示:Si-Cu热还原制镁反应的热力学临界温度随系统气压降低及Si-Cu中Si含量增加而减小;对应于常规真空硅热还原制镁(皮江法)温度(1473 K)和系统气压(13.3 Pa),Si-Cu合金中的Si含量只需高于0.034%,Si-Cu热还原制镁即具备热力学可行性。     

ScF3冰晶石熔盐体系中铝热还原Sc2O3制备Al-Sc中间合金

在nNaF.AlF3—KCl—NaCl熔盐体系中,用液态铝还原Sc2O3制备Al—Sc中间合金,加入适量的ScF3,可以提高Sc2O3在熔盐体系中的溶解度,从而提高Al—Sc中间合金中钪的含量(可达2%)和钪的收率以及Al—Sc中间合金的质量,降低Al—Sc中间合金的生产成本,并为Al—Sc中间合金的广泛应用创造有利条件。     

稀土硅化物中间合金

本文介绍了使用碳热还原一步法生产的稀土硅化物中间合金的物理特性和应用特点。     

坩埚冷却系统改造对中间合金熔炼的影响

以Zr-Sn—Fe—Cr—Ni合金为研究对象,通过2次非自耗真空电弧熔炼制备出中间合金,对熔炼中间合金时所采用的坩埚的冷却系统进行了改造,对比了改造前后中间合金的熔炼过程,并采用OM、EDS研究了中间合金的组织及化学成分,冉以添加中间合金扣方式压制电极,利用真空自耗电极熔炼方式制备出吨级锆合金铸锭,并对成品铸锭的成分进行跟踪。结果表明：在坩埚中加入导流槽后,中间合金的熔炼效率得到了提高,熔炼时难脱模现象大大缓解;采用加导流槽后的坩埚经过2次熔炼可以制备出成分均匀的中间合金,合金组织由柱状品和树枝晶组成,与未加导流槽时所熔炼的合金相比,组织及成分更加均匀;采用冷却系统改造后的坩埚熔炼的中间合金可以制备出成分均匀的工业规模级锆合会铸绽。     

Achieving enhanced ductility in a dilute magnesium alloy through severe plastic deformation

Experiments were conducted to evaluate the utility of a new processing procedure developed for Mg-based alloys in which samples are subjected to a two-step processing route of extrusion followed by equal-channel angular pressing (designated as EX-ECAP). The experiments were conducted using a Mg-0.6 wt pct Zr alloy and, for comparison purposes, samples of pure Mg. It is shown that the potential for successfully using ECAP increases in both materials when adopting the EX-ECAP procedure. For the Mg-Zr alloy, the use of EX-ECAP produces a grain size of ∼1.4 μm when the pressing is undertaken at 573 K. By contrast, using EX-ECAP with pure Mg at 573 K produces a grain size of ∼26 μm. Tensile testing of the Mg-Zr alloy at 523 and 573 K after processing by EX-ECAP revealed the occurrence of significantly enhanced ductilities with maximum elongations of ∼300 to 400 pct.     

Effect of Scandium on Corrosion Resistance of Welded Joint of Al-6Mg-Zr Alloy

Al Mgalloyshavebeenwidelyusedinmanyin dustries,especiallyinmarineandaircraftapplica tions,duetotheirgoodweldability,ductilityandex cellentcorrosionresistance.Beingthenon heattreat ablealloys,thesematerialsderivetheirstrengthpri marilyfromsolidsolutio…     

从稀土储氢合金冶炼废渣中回收稀土镍钴合金的研究

对于稀土储氢合金冶炼废渣粉,采用水热酸溶-还原扩散-电弧熔炼的方法回收稀土氧化物和稀土镍钴合金。废渣粉首先用水热酸溶法分离其中的部分稀土氧化物,得到的合金富集物配加金属钙粒用还原扩散法将其中剩余的稀土氧化物转化为AB5型合金,还原扩散得到的合金粉采用电弧熔炼得到稀土镍钴合金。回收的合金杂质含量低,可作为基础原料用于熔炼AB5型稀土储氢合金,实现了稀土储氢合金冶炼废渣的循环利用。     

Grain refinement of Mg-3Y alloy using Mg-10Al_2Y master alloy

The as-extruded Mg-10 Al_2 Y master alloy was chosen as a novel grain refiner for as-cast Mg-3 Y alloy.Contrast samples of cast Mg-3 Y alloy added with pure Al and Mg-Zr master alloy grain refiners were prepared under the same conditions.In this study,the influence of addition amounts of Al_2 Y and holding time on grain refinement efficiency as well as tensile properties was investigated.And the grain refining ability of the Al_2 Y particles was systematically evaluated in terms of the addition amounts,number density of the Al_2 Y particles and holding time.The finest grains are achieved at 2 wt% Al_2 Y addition amount,which corresponds to number density of the polygonal Al_2 Y particles of 420-460 mm~(-2).The Mg-10 Al_2 Y master alloy has significant refinement performance and no refining recession occurs at the holding time within 60 min,or the settling time up to 180 min.Grain refinement and the second phase strengthening of uniformly distributed Al_2 Y particles contribute to the simultaneous enhancement on both strength and elongation of Mg-3 Y alloy.     

45Ag-30Cu-25Zn合金丝制造工艺的探讨

熔炼时通过控制锌的加入方式、熔化功率、精炼时间、以及锌的挥发量,在选用多种开坯工艺比较了合金丝材的成品率、拉拔过程中选择合理的变形量及中间退火次数后,成功的生产出表面质量好,成品率80%以上的45Ag-30Cu-25Zn 合金丝材。     

包头铌铁矿冶炼实验研究

针对包头矿高铁低铌的特点提出了选择性还原-熔分-铌铁冶炼的处理方案,并对方案的三个关键步骤进行了实验研究。结果表明,熔分阶段铌回收率在95%以上,冶炼阶段铌回收率在85%以上,全流程铌回收率>80%,铌磷Nb/P>15。本流程完全可综合回收包头矿中的铌、铁、锰等元素。     

Study of Microbiologicaily Induced Corrosion Action on Al-6Mg-Zr and Al-6Mg-Zr-Sc

The corrosion behaviors of Al-6Mg-Zr and Al-6Mg-Zr-Sc in the sulfate-reducing bacteria （SRB） solution in anaerobic environment were studied using electrochemical, microbiological, and surface analysis methods. It was found that the oxide film was more compact owing to the addition of Sc resulting in the open circuit potential shifting by about 100mV positively. On the other hand, it was seen that the pitting sensitivity of Al-6Mg-Zr-Sc alloy in SRB solution decreased and its microbiologically influenced corrosion resistance was improved. Pitting corrosion occurring on the surface of the two alloys under the comprehensive action of the metabolism of SRB was observed by SEM. It was obtained by EDS that the corrosion degree increased with time and corrosion was furthered by deposition of the product.     

Thermo-mechanical processing of Cu-Cr alloys prepared by using electro slag crucible melting

Cu-Cr ingots of Cr contents of up to 2 Wt % were prepared by melting copper scrap using electroslag crucible melting (ESCM). Chromium addition to copper was carried out by in-situ reduction of chromium oxide present in the slag. The Cu-Cr ingots produced were subjected to up to 90% rolling reduction using different combination of rolling and heat treatment. A range of microstructure and mechanical properties was obtained. Alloys with recrystallised microstructure exhibited lower strength and higher ductility. The alloys prepared by ESCM compare well with Cu-Cr alloys reported in the literature. The ESCM route is more attractive as it uses copper scrap for melting and in-situ reduction of chromium oxide for alloying of chromium. ESCM also enables preparation of alloy with high (up to 2%) Cr content.