组成对MgO-ZrO2-CaO系合成料结构与性能的影响

以脱硅锆、轻烧氧化镁、消石灰为原料，进行了MgO-ZrO2-CaO系原料的合成，研究了化学组成(包括ZrO2含量、CaO／ZrO2比)，烧成温度，杂质等对合成料性能和组织结构的影响。     

MgO-ZrO2-CaO合成料抗水化性的研究

研究了MgO-ZrO2-CaO合成料中ZrO2含量、m(CaO)／m(ZrO2)比、杂质等对合成料抗水化性的影响，并从不同方面对合成料的抗水化性进行了评价。试验表明，当合成料中存在游离CaO时，合成料会发生水化，且抗水化性随m(Ca0)／m(ZrO2)比的增大而降低；当合成料中m(CaO)／m(ZrO2)比一定时，合成料抗水化性随ZrO2含量的增加而降低；杂质的存在有利于合成料抗水化性的提高；当m(CaO)／m(ZrO2)比≤1．3时，合成料可用于浇注料，不易发生水化。     

Impedance Characteristics of MgO-ZrO2 Ceramics Doped with CeO2

The ultrafine CexMg0.06Zr1-xO1.94 （ x = 0 16% ） powders were synthesized by a chemical co-precipitated method. The pressed compacts were sintered in air at 1300, 1400, 1500, 1600℃ for 3 h, respectively. The phase of the ceramics was characterized by the X-ray diffraction （XRD） method. The conductivity of the ceramics was measured by the AC complex impedance technique at 700- 1200 ℃. The ratio of the cubic phase in the ceramics improves with increasing CeO2 content, leading to a enlargement of the oxygen ionic migration channel. The contact resistance between conductive phase particles decreases with increasing CeO2 content, leading to a lower migration hindrance of the oxygen ionic. Consequently, the ionic conductivity of the ceramics improves with increas- ing CeO2 content. Additionally, an analysis for this phenomenon was also presented.     

RH用MgO-ZrO2材料抗渣侵蚀机理的研究

研究了RH精炼无取向硅钢和取向硅钢的炉渣对镁锆砖侵蚀的机理.结果表明,镁锆砖抵抗高CaO含量的无取向硅钢渣的侵蚀机理是生成致密的CaZrO3保护层,而抵抗高SiO2和高CaO含量取向硅钢渣的侵蚀机理是生成CaZrO3和C2S致密层.两者都是通过炉渣和基质中的ZrO2反应使得方镁石晶界中的气孔堵塞,从而阻止炉渣对耐火材料的进一步侵蚀.     

ZrSiO4对高铝制品热震稳定性能的影响

通过添加ZrSiO4对高铝制品抗热震性能影响的研究，认为其机理是在高温下ZrSiO4生成压ZrO2，ZrO2相变形成显微裂纹增韧，裂纹扩展及显微结构改善，提高了制品的热震稳定性。     

新型YWR_2稀土硬质合金的使用性能与显微结构

YWR_2是在YW_2基础上通过添加微量稀土添加剂所获得的硬质合金新牌号,本文利用正交试验的方法获得了最佳稀土添加形态、添加量、添加方式,该稀土合金具有优良的物理机械性能和使用性能,同条件下,在硬度不变甚至略有提高的情况下,抗弯强度和抗冲击韧性值比YW_2都提高10％以上,十多家用户使用结果表明,YWR_2的平均耐用度为YW_2的1倍以上。 采用电子探针、扫描电镜、金相仪等手段研究了稀土在YWR_2合金中的存在形式和分布状态以及对粘结相,硬质相、相界面等的影响。从YWR_2和YW_2合金的显微结构比较,阐述了稀土改善YW_2合金性能的作用机理。     

CaZrO3材料的制备及其显微结构

CaZrO₃在CaO-ZrO₂体系化合物中CaO含量最高且最稳定的一种化合物.利用CaCO₃和m-ZrO₂为原料在1450℃预先合成后又于1600℃重烧,其CaZrO₃晶粒发育更加完善.利用这种方法合成的CaZrO₃为原料,不添加助烧剂在1700℃时就可以获得接近理论密度的烧结体,其显微结构特征是CaZrO₃颗粒紧密堆积,而且晶形发育极其良好.     

硫酸锆制备工艺研究

介绍了氢氧化钠碱熔分解锆英石，经水洗、酸浸出、结晶等制取硫酸锆的工艺流程、技术条件及试验结果，制得的产品含ＺｒＯ２３４％，杂质含量少。     

ICP-AES法测定锆英砂、电熔脱硅锆中Fe_2O_3、Al_2O_3、TiO_2、Cr_2O_3的质量分数

为测定锆英砂、电熔脱硅锆中Fe_2O_3、Al_2O_3、TiO_2、Cr_2O_3的含量,研究了用无水碳酸钠、无水碳酸钾、四硼酸钠混合熔剂熔融试样,在一定酸度下,用锫基体打底绘制工作曲线,将溶液雾化导入ICP,同时测定Fe_2O_3,Al_2O_3,TiO_2,Cr_2O_3发射光强度,计算各元素的质量分数。经实践该方法可操作性强,测量精确,可及时指导生产。     

电熔MgO及MAT细粉对刚玉质材料性能的影响

以电熔刚玉、电熔MgO及电熔MgO-Al2O3-TiO2细粉为原料,实验并研究了电熔MgO及电熔MgO-Al2O3-TiO2细粉的添加对刚玉质材料性能的影响.结果表明,经中、高温热处理后,添加MgO-Al2O3-TiO2细粉的刚玉质浇注料的各项性能明显好于添加MgO细粉的刚玉质浇注料.     

Influences of material parameters and microstructure on superplastic forming

The strain rate sensitivity of flow stress has long been recognized as an important factor in determining superplastic ductility, and its relationship to high tensile elongations is well understood from the mechanics point of view. However, the measurements of this parameter and other properties of superplastic materials are challenging, and quite varied results are observed from different test procedures used. In this paper a discussion of the various characterization methods is presented, and the relationship between the superplastic characteristics and the microstructure is brought forth. The applicability of the uniaxial superplastic properties on the biaxial deformation behavior as in the superplastic forming process is addressed, including a relationship of such properties to the selection of forming parameters. This paper is based on a presentation made at the symposium “On the Mechanical, Microstructural and Fracture Processes in Superplasticity” held at the annual meeting of the AIME in Pittsburgh, PA on October 7, 1980 under the sponsorship of the Flow and Fracture Activity of the Materials Science Division of ASM.     

预合成镁锆砖抗AOD渣侵蚀性的研究

通过将轻烧镁粉和脱硅锫按不同配比混合、压坯，经1800℃高温烧成、预合成出ZrO2含量为2％、3．2％、5．4％的镁锫砂。然后利用预合成的镁锫砂，制成ZrO2均匀分布、集中分布在颗粒中和集中分布在细粉中三种ZrO2含量为2％的试样，经1800℃高温烧成后，通过其对C／S=2．32的AOD炉渣的抗侵蚀性的研究，得出了预合成镁锫砖中ZrO2在基质中分布的镁锫砖抗渣渗透性最好。     

Computer simulation for microstructure evolution in a polydisperse material on sintering. Part 2. Zoned segregation

Translated from Poroshkovaya Metallurgiya, No. 5(341), pp. 5–10, May, 1991.     

Study on preparation,microstructure and luminescent properties of Er-ZrO_2 layer

To further explore the material early-warning application of the luminescent coating,we demonstrated a new method by preparing a mixture layer of metallic erbium and oxidized zirconium(Er-ZrO_2 layer) using the double glow plasma surface alloying technology with Zr and Er co-sputtering under oxygen plasma exposure.The microstructure,composition and luminescence properties of the layers were characterized by scanning electron microscopy,X-ray diffraction,Raman and photoluminescence spectra.The dependence of the luminescence on the gradual concentration was studied.Results indicated that the contents of Zr,Er and O in the layer decreased gradually along the depth direction.The luminescence properties were concentration-dependent.X-ray diffraction analysis showed that the crystalline structure of ZrO_2 layer transferred from a mixture phase of tetragonal and monoclinic to pure monoclinic phase with the Zr-Er co-sputtering.The Raman bands of the layers depended on its local ZrO_2 crystal structures.Photoluminescence characteristics of Er-ZrO_2 layer revealed that the main emission bands were assigned to ~2H_(11/2)→~4I_(15/2) and ~4S_(3/2)→~4I_(15/2) transition under the excitation at 325 nm.The fact suggested that the plasma surface alloying is an effective method to obtain luminescent layer.     

感应烧结工艺对Fe基粉末冶金材料组织与性能的影响

采用感应加热对不同密度和不同C含量的压坯在不同温度下进行烧结,通过金相观察和力学性能测试分析感应烧结技术对Fe基粉末冶金材料组织和性能的影响.研究结果表明:感应加热会使粉末颗粒在界面处产生较高的温度,促进了C向Fe中的溶解与扩散,有利于Fe、C的化合;当C含量较多时,经感应烧结后的试样珠光体含量明显多于普通电阻炉烧结后...     

特种钨合金电极材料制备工艺及组织性能研究

制备了W–Ni–Ca、W–Ni–Sr、W–Ni–Ba三种钨合金电极材料,研究了三种钨合金电极材料的组织性能。结果表明:W–Ni–Ca电极材料难烧结,组织不均匀,性能较差;W–Ni–Ba在烧结过程中生成的钨酸钡熔点较低,对电极抗烧蚀性能不利;通过对三种电极材料进行比较分析,认为W–Ni–Sr具有最佳的组织和性能。