钢包精炼用透气塞

在钢包精炼中,气体通过安装在钢包底部的透气塞注入钢液中搅拌钢水,以促进钢水温度和化学成分均匀。品川耐火材料公司生产的ALP系列和HSP系列透气塞,优化了多孔砖的组织。新开发的多孔材质HSP206,改善了耐氧气清洗熔损性。     

铝用泡沫陶瓷过滤器现状与应用趋势

简述了过滤净化对于铝及铝合金熔铸的重要意义,通过国内外现有铝用泡沫陶瓷过滤器(CFF)的对比分析,提出了国内铝用CFF在性能与应用方面存在的问题以及面临的竞争,并从材料、制备工艺、效用评价等方面提出了改善铝用CFF性能的若干措施。     

大型精炼钢包用刚玉-尖晶石质透气砖的研制与使用

为满足大型精炼钢包对透气砖的要求,通过配方优化、高温烧成等技术手段,成功开发了性能和使用效果优于传统铬刚玉质透气砖的刚玉-尖晶石质透气砖。该透气砖以板状刚玉为颗粒料,以电熔白刚玉为细粉,并加入6%纯铝酸钙水泥、5%活性α-Al_2O_3微粉和8%尖晶石,另外加入适量氧化铬和减水剂,经振动成型、干燥后于1500℃保温3h以上烧成。该透气砖在大型精炼钢包上使用,取得了满意的使用效果。     

钛酸铝陶瓷及其研究现状

本文简述了钛酸铝陶瓷的制备及性能,论述了钛酸铝陶瓷的稳定性、微裂纹、低热膨胀性,讨论了工艺条件及外加剂对钛酸铝材料性能的影响,最后提出了改善钛酸铝陶瓷性能的技术途径。     

精炼钢包用透气砖的研究进展与发展方向

总结了精炼钢包用透气砖的损毁原因和现用刚玉-尖晶石透气砖在改善抗热震性方面的研究新进展;介绍了非氧化物结合刚玉质透气砖的研究结果和在精炼钢包上的使用情况,提出了透气砖的研究和发展方向。     

铜熔体的精炼净化技术

本文详细的介绍了铜熔体精炼净化过程中除杂、脱气、脱氧的各种技术现状,分析了铜熔炼所用熔剂的基本要求。     

精炼铝炉用刚玉-镁铝尖晶石复合材料的制备与性能

用白刚玉、镁铝尖晶石、电熔镁砂和α-Al2O3微粉,在1 650 ℃烧结3h制备了刚玉-镁铝尖晶石复合材料.按照GBT29971982致密定形耐火制品气孔率和体积密度试验方法和静态坩埚法,并结合X射线衍射、扫描电镜和能谱分析研究了不同组成刚玉-镁铝尖晶石复合材料的常温物理性能、显微结构以及将其应用于精炼铝熔融炉用耐火材料时对高纯度铝的影响.结果表明:在1 650 ℃保温3 h的条件下,试样烧结致密,基质中有镁铝尖晶石生成;所制备的试样中,当α-Al2O3微粉与电熔镁砂的质量比为2∶1时,试样具有较好的室温物理性能,并且对高品质铝液的污染很小.     

Cracking mechanism in laser directed energy deposition of melt growth alumina/aluminum titanate ceramics

Thanks to its advantages of high efficiency and near-net shaping, laser directed energy deposition (LDED) is rapidly becoming a remarkable preparation technology for high-purity ceramics. However, the cracking problem in shaping process is always a great challenge for LDED to achieve industrial application. For this purpose, alumina/aluminum titanate melt-growth ceramics (A/AT MGCs) were prepared using LDED system, and the corresponding finite element thermal analysis model was developed. The solidification behavior and cracking mechanism of A/AT MGCs were investigated based on the thermal analysis model, and the influence of process parameters on the cracking characteristics was revealed with experiments. Results show that the crack morphology and distribution are controlled by microstructure and temperature gradient together. The scanning speed of 100–150 mm/min, with better microstructure and lower temperature gradient, is a preferred process window. This study provides theoretical guidance and technical support for the cracking suppression during LDED shaping of ceramics.     

铝及铝合金阳极氧化、着色及封闭的现状和发展趋势

综述了铝及其合金阳极氧化、电解着色及封闭的研究，应用现状及工艺改进。着重介绍了铝阳极氧化，包括普通阳极氧化、硬质阳极氧化和微弧阳极氧化。介绍了微弧阳极氧化陶瓷膜的性能及工艺改进，针对铝阳极氧化在今后的研究方向提出了建议。     

中国铝铁盐工业的现状及发展趋势

论述了中国铝铁盐工业的发展历程、发展现状、目前存在的问题和今后的发展趋势,旨在对中国铝铁盐工业的健康发展提供重要参考。详细介绍了中国铝铁盐工业的主要产品品种（硫酸铝、聚氯化铝、聚合硫酸铁、氯化铁、明矾）、企业生产规模、生产工艺、技术水平、创新动态、生产装备及应用现状,铝铁盐产品主要用于水处理、造纸、速凝剂、食品添加剂等领域,生产过程中的废水封闭循环利用、废渣用作建筑材料、废气综合治理。分析了中国铝铁盐工业目前存在的主要问题,提出了铝铁盐工业存在同质化竞争、粗制滥造、研发投入不足、应用开发滞后等问题。指出了今后铝铁盐工业的发展趋势,即市场需求缓中有增、产能将向优势企业集中、创新产品品种和应用范围带来新的市场需求、打造名优品牌以优驱劣等。     

Phase composition,crystal structure,and microwave dielectric properties of Nb-doped and Y-deficient yttrium aluminum garnet ceramics

Nb-doped and Y-deficient yttrium aluminum garnet ceramics were designed and synthesized using the solid-state reaction method according to the chemical equation Y_3?xAl₅Nb_xO_12+x (0 ≤ x ≤ 0.16). The phase composition, sintering behavior, microstructure, and microwave dielectric properties were investigated as functions of the composition and sintering temperature. A single-phase solid solution of yttrium aluminum garnet structure formation was observed in the range of 0 ≤ x ≤ 0.1. Further increments in x prompted the precipitation of the YNbO₄ secondary phase at the grain boundary of Y₃Al₅O₁₂. The complexity of the phase composition degrades the micromorphology and dielectric properties of the ceramics to varying degrees. Transmission electron microscopy results show that the lattice exhibits additional symmetry, which is closely related to the ultrahigh Q×f values of the ceramics. Effectively improving the sintering behaviour and suppressing the secondary phase by simultaneously doping with Nb⁵⁺ and reducing the yttrium stoichiometry. Finally, excellent microwave dielectric properties of ε_r ~ 10.99, Q×f ~ 280,387 GHz (13.5 GHz), and τ_f ~ ? 34.7 ppm/°C can be obtained in x = 0.1 (Y_2.9Al₅Nb_0.1O_12.1) sintered at 1700 °C for 6 h.     

超纯净金属冶炼用CaO耐火材料的研究进展

分析了使用CaO坩埚对Ni、Fe基合金精炼的机制 ;列举了CaO坩埚精炼在电子学、超导母合金等领域的一些成功应用的例子 ;总结了在先进结构材料 (包括航空和航海仪器铸件、航空发动机高温合金铸件 )方面的应用 ;展望了CaO坩埚精炼的前景     

Effects of added aluminum chromium slag on the structure and mechanical properties of colored zirconia ceramics

Colored zirconia ceramic samples were prepared via pressureless sintering with yttria-stabilized zirconia as a raw material and aluminum chromium slag (ACS) as an additive. Then, the effects of added ACS (0-15.0 wt%) on the microstructure, phase composition, and mechanical properties of the ceramic were investigated. The addition of ACS changed the apparent color of zirconia ceramics from white to pink, and the color deepened as the ACS content increased. In addition, more pores appeared in the sintered ceramic substrate as the content of ACS increased, and the relative density of samples declined from 97.7% to 91.1% with an increase in ACS content. However, the microhardness and bending strength each reached their maximum values (1887.2 HV and 433.5 MPa, respectively) when the content of ACS was 5.0 wt%. Fracture surface analysis of the samples showed that intergranular fractures were the main features of sintered samples with no added ACS, whereas numerous transgranular fractures occurred in sintered samples to which ACS had been added. The XRD results revealed that the prepared mainly composite ceramics were composed of t-ZrO₂, m-ZrO₂, and chromium-corundum, and the content of the t-ZrO₂ gradually increased as the ACS content increased.     

中国铝盐行业现状及发展趋势

介绍了中国铝盐行业的主要产品品种(硫酸铝、聚氯化铝、明矾)、企业生产规模、生产技术水平、生产装备及产品应用现状。铝盐产品主要用于水处理、造纸、食品添加剂等行业。随着造纸工业和水处理工业的快速发展,中国铝盐行业生产规模不断扩大,生产技术水平不断提高,产业集中度不断增加,产品除满足国内需求外出口数量也逐年增加。同时也提出了铝盐行业存在的问题,如低水平重复建设、市场无序竞争等。指出了铝盐行业的发展趋势,如铝盐产品市场需求总量将持续增加、铝盐新产品及新用途的研究将得到重视等。     

Synthesis of SiBNC-Al ceramics with different aluminum contents via polymer-derived method

This study reports the synthesis of three types of aluminium (Al)-modified polyborosilazane ceramic precursors (PBSAZ) from C₈H₁₉Al/HSiCl₃/HMDZ/BCl₃ and their thermal conversion to SiBNC-Al ceramics at 1000°C. FT-IR, nuclear magnetic resonance (NMR), X-ray photoelectron spectroscopy (XPS), and thermogravimetric analysis (TGA) are used to characterize the structures and properties of the PBSAZ. PBSAZ is found to be built up of the Si─N─B framework, with Al successfully introduced into the ceramic network structures. The ceramic yield is 63.5 wt.% for the Al-poor polymers (PBSAZ-5) and 65.1 wt.% for the Al-rich polymers (PBSAZ-1). The high-temperature cracking behavior and the crystal phase structures of the ceramics were characterized by XRD and Raman, which revealed that SiBNC-Al ceramics contained Si₄N₃, SiC, and AlN (+SiC) crystals after heat treatment at 1600°C. The oxidation behavior of SiBNC and SiBNC-Al ceramics at 1500°C shows that the introduction of Al improves the quality of the oxide layer, effectively suppresses the oxide layer cracking phenomenon, and reduces gas bubble generation.     

Porous ceramics with near-zero shrinkage and low thermal conductivity from hazardous secondary aluminum dross

Herein, a simple, versatile, and low-cost approach has been proposed to realize the green utilization of secondary aluminum dross, the hazardous solid waste, namely directly sintering dry-pressed green bodies from secondary aluminum dross to fabricate porous ceramics according to high-temperature foaming process spontaneously without adding spare foaming agents. Aluminum nitride (AlN) in secondary aluminum dross was employed to realize high-temperature foaming due to its oxidation, which makes traditional AlN and salts removal process needless. Moreover, near-zero shrinkage or even expansion during sintering of porous ceramics have occurred because in-situ foaming process together with the oxidation of Al particles well offset the sintering shrinkage. After sintering at 1400°C for 2 h, porous ceramics composed of α-Al₂O₃ and spinel phases with open porosity of 37.91%, sintering expansion rate of 1.13%, flexural strength of 45.67 MPa, and thermal conductivity of 0.97 W/(m·K) have been prepared. Cenospheres as pore-forming agents have been added to further improve the porosity, and alumina-based porous ceramics with open porosity of 28.39%–43.20% and flexural strength of 15.80–52.48 MPa have been obtained. This effective solution for recycling secondary aluminum dross could supply high-performance porous ceramics, which is expected to be applied in the fields of light-weight structural components and thermal insulations.     

无味煤油精制技术的研究进展

介绍了无味煤油精制的新技术、新方法,分析了煤油型无味溶剂油气味的产生因素。从消除或抑制这些影响因素出发,介绍了目前国内外的最新研究进展。指出为满足国内外市场对特种溶剂油产品的迫切需求,应大力开发新的溶剂油精制技术,以提高我国溶剂油产品的竞争力。