一种两室式蓄热焚烧炉优化改造方案

介绍两室式蓄热焚烧炉工作原理及特点,并针对两室式蓄热焚烧炉的不足,以三室式蓄热焚烧炉原理为出发点,提出一种对两室式蓄热焚烧炉的优化改造方案,并给出具体实施细节及注意事项,这种方案能大大提高废气处理效率。     

蓄热焚烧炉特点及发展趋势探究

介绍蓄热焚烧炉工作原理，两室式、三室式、旋转式三种蓄热焚烧炉分类方式及工作流程，并对三种蓄热焚烧炉优缺点进行对比总结，最后对蓄热焚烧炉未来发展趋势进行探究。     

快速成型制备Al-Si/粉煤灰基高温相变蓄热球的尺寸效应

以Al-Si共晶合金粉为相变介质、粉煤灰为基体材料,采用干法快速成型及混合烧结法制备了不同直径的(10、15和20 mm)陶瓷基高温相变蓄热球.结果 表明:不同直径蓄热球的成型压力及性能存在显著差异.素坯成型时,压力分解为使其致密的向心力以及耗散掉的切向力,直径大则向心力大,但压力传递深度有限,素坯尺寸越大越难完全致密,易产生硬化层,导致蓄热球中合金粉颗粒破裂加剧、相变潜热降低.不同直径蓄热球的成型压力范围分别为:φ10 mm,1～6 MPa;φ15 mm,2～6 MPa;φ20 mm,4～10 MPa.φ10 mm蓄热球在压力为1MPa时相变潜热较高(92.47 J·g-1),但密度较低(1.57 g·cm-3).φ15 mm蓄热球在2～4 MPa时综合性能良好,相变潜热为105.54～90.68 J·g-1、密度为1.64～ 1.89 g·cm-3.φ20 mm蓄热球均存在硬化层,相变潜热偏低,小于40 J·g-1.     

蓄热式连续加热炉应用中若干问题研究

介绍了蓄热式连续加热炉在国内钢铁企业中的应用现状；深入分析了其推广应用的适用性、蓄热室的蓄热能力难以满足生产要求、加热炉运行中炉压较大且易波动、自动化控制水平不高等问题；提出了应加强在蓄热式加热炉结构型式选择、蓄热室同炉膛耦合传热、炉内气体限制射流与自动化控制等方面的研究，不断改善其不足，推动其发展。     

蓄热式加热炉的维护

以唐山钢铁股份有限公司中型厂蓄热式加热炉为例，对影响加热炉使用的蓄热体板结、蓄热室漏火漏气，以及换向阀不到位的问题进行了分析，并介绍了解决其问题的有效措施。     

影响蓄热式加热炉使用效果的原因分析

对蓄热式加热炉在使用过程中遇到的加热能力不足、蓄热室易积水等问题进行了分析，指出在蓄热式燃烧技术应用过程中，也应遵循传统的加热炉设计理论，并应对煤气进行更严格的脱水处理。     

湿法球磨工艺参数对硅酸锆平均粒度的影响

对锆英砂湿法球磨加工中存在的问题进行了概述和分析,研究了湿法球磨中的球磨机转速、研磨时间、浆料浓度、填充率、球料比等工艺参数对硅酸锆的平均粒度的影响规律。研究结果表明,增加球磨机的转速,延长球磨时间,都会使研磨出的硅酸锆粒度变得更小,且硅酸锆平均粒度变化曲线都呈初期变化大,超过拐点后变化减缓的趋势。填充率和浆料浓度对硅酸锆平均粒度的影响类似,随着填充率或浆料浓度的不断增加,研磨出来的硅酸锆粒度越小,但总体上下降幅度不大,其变化幅度的差别主要来自于罐中水和空气的比例不同。球料比对硅酸锆的平均粒度影响显著,当球料比在2∶1到6∶1的范围内变化时,随着球料比增大,研磨出来的硅酸锆的平均粒度由6.55μm下降到1.82μm。     

蓄热室内置式加热炉炉体损坏原因与修复

介绍了蓄热室内置式加热炉的特点，分析了其炉体发生损坏的原因，并提出了已经实践检验的相应修复方法。     

昆钢炉卷轧机加热炉蓄热式节能改造实践

介绍了武钢集团昆明钢铁股份有限公司炉卷轧机加热炉蓄热式节能技术的改造。通过改造前后相关参数的比较,表明了焦炉煤气常规板坯加热炉改造为高炉煤气双蓄热加热炉的技术可行性。     

紧实度均匀的高速射砂造型

铸造工作者认为,硬度得当且紧实度比较均匀的铸型在液态金属静压作用下产生最小的型壁移动。这种铸型能复制出与模样尺寸一致的铸件。为实现此目的,用均匀填砂法填充造型室是绝对必要的。填充这类造型室的最有效方法是用压缩空气使型砂流态化,使型砂能以很高的速度进入造型室。在填充造型室时,为使型砂获得最大的流动性,采用双室结构的射砂头。内室A系重力     

Three-Dimensional Growth of Coherent Ferrite in Austenite: A Molecular Dynamics Study

Coherent second phase often exhibits anisotropic morphology with specifi c orientations with respect to both the second and the matrix phases. As a key feature of microstructure, the morphology of the coherent particles is essential for understanding the second-phase strengthening eff ect in various industrial alloys. This letter reports anisotropic growth of coherent ferrite from austenite matrix in pure iron based on molecular dynamics simulation. We found that the ferrite grain tends to grow into an elongated plate-like shape, independent of its initial confi guration. The fi nal shape of the ferrite is closely related to the misfi t between the two phases, with the longest direction and the broad facet of the plate being, respectively, consistent with the best matching direction and the best matching plane calculated via the Burgers vector content(BVC) method. The strain energy calculation in the framework of Eshelby's inclusion theory verifi es that the simulated orientation of the coherent ferrite is energetically favorable. It is anticipated that the BVC method will be applicable in analysis of anisotropic growth and morphology of coherent second phase in other phase transformation systems.     

RHEOLOGY FEATURE OF SIMPLE METAL MELT

The rheology feature of Sb, Bi melt and alloys was studied using coaxial cylinder high-temperature viscometer. The results showed that the curve of torsion-rotational speed for Sb melt presents a linear relation in all measured temperature ranges, whereas for the Bi melt, the curve presents obvious non-Newtonian feature within the low temperature range and at relative high shear stress. The rheology feature of Sb80Bi20 and Sb20Bi80 alloy melts was well correlated with that of Sb and Bi, respectively. It is considered that the rheology behavior of Sb melt plays a crucial role in Sb80Bi20 alloy and that of Bi melt plays a crucial role in Sb20Bi80 alloy.     

Microstructures and Mechanical Properties of a Newly Developed Austenitic Heat Resistant Steel

The effect of heat treatment on the microstructures and mechanical properties of a newly developed austenitic heat resistant steel(named as T8 alloy) for ultra-supercritical applications have been studied. Results show that the main phases in the alloy after solution treatment are γ and primary MX. Subsequent aging treatment causes the precipitation of M_(23)C_6 carbides along the grain boundaries and a small number of nanoscale MX inside the grains. In addition, with increasing the aging temperature and time, the morphology of M_(23)C_6 carbides changes from semi-continuous chain to continuous network.Compared with a commercial HR3C alloy, T8 alloy has comparable tensile strength, but higher stress rupture strength. The dominant cracking mechanism of the alloy during tensile test at room temperature is transgranular, while at high temperature, intergranular cracking becomes the main cracking mode, which may be caused by the precipitation of continuous M_(23)C_6 carbides along the grain boundaries. Typical intergranular cracking is the dominant cracking mode of the alloy at all stress rupture tests.     

Effect of Short-Time Aging on the Pitting Corrosion Behavior of a Novel Lean Duplex Stainless Steel 2002

The effect of short-time aging in the temperature range between 400 and 1000 °C on the pitting corrosion behavior and mechanical property of a novel lean duplex stainless steel(LDSS) 2002 was investigated through the potentiostatic critical pitting temperature(CPT) tests and the Charpy impact tests. Both the pitting corrosion resistance and the toughness of aged specimens degraded due to the precipitation of detrimental secondary phases and the most significant reduction of CPT and impact energy emerged at 650 °C concurrently. The CPT of LDSS 2002 specimen aged at 650 °C decreased by 28 °C, and the impact energy dropped from 69 to 29 J/cm~2 compared with the solution-annealed sample. Transmission electron microscopy characterization showed that the main precipitates in LDSS 2002 were Cr_2N and M_(23)C_6 along the ferrite–austenite grain boundaries.     

INTRODUCTION TO PATENTS

The invention provides a method of making a mold which can reduce SOx generation rate while preventing decrease in hardening rate in the case of using sulfuric acid for a hardener composition. The method has a mixture step in which fire-resistant particles, a hardener composition and a binder composition are mixed to obtain a composition for a mold. The hardener composition contains sulfuric acid. In the mixture step, sodium carbonate is added. A molar ratio of the sulfuric acid to the sodium carbonate is 0.5 or more and 4.0 or less.     

China Foundry Week 2014

China Foundry Week, hosted by the Foundry Institution of Chinese Mechanical Engineering Society （FICMES） each year, is a large academic event in China. It is one of the ten high-impact activities sponsored by the Chinese Mechanical Engineering Society.     

17th Conference of Hydrodynamic and Electromechanical Control Engineering Call for papers

正1.Contents In order to promote the academic exchanges and technical communication of the research in the field of fluid power transmission and control,fluid control engineering specialized committee of the Chinese Society of Theoretical and Applied Mechanics will hold the 17th Conference of Hydrodynamic and Electromechanical Control Engineering on July 27-29,2014 in Tibet,Lhasa city.     

Information for Contributors

正The Transactions of Nonferrous Metals Society of China,founded in 1991 and sponsored by The Nonferrous Metals Society of China,is published monthly now and mainly contains reports of original research which reflect the new progresses in the field of nonferrous metals science and technology,including mineral processing,extraction metallurgy,metallic materials and heat treatments,metal working,physical metallurgy,powder metallurgy,with the emphasis     

Preface

<正>We are pleased to present this Special Issue of Transactions of Nonferrous Metals Society of China containing selected papers from the First Asian Conference on Aluminum Alloys(ACAA-2013),held in Beijing,China,13–17 October 2013.This conference has been initiated,with approval of     

Information for Contributors

The Transactions of Nonferrous Metals Society of China, founded in 1991 and sponsored by The Nonferrous Metals Society of China, is published monthly now and mainly contains reports of original research which reflect the new progresses in the field of nonferrous metals science and technology, including mineral processing, extraction metallurgy, metallic materials and heat treatments, metal working, physical metallurgy, powder metallurgy, with the emphasis on fundamental science. It is the unique preeminent publication in English for scientists, engineers, under/post-graduates on the field of nonferrous metals industry. This journal is covered by many famous abstract/index systems and databases such as SCI Expanded, Ei Compendex Plus, 1NSPEC, CA, METADEX, AJ and JICST.