不锈钢冶炼工艺技术

简述了不锈钢冶炼原料及工艺路线的发展,重点介绍了不锈钢冶炼各工序的生产工艺,为不锈钢冶炼工艺路线的选择提供参考。     

转炉冶炼40Cr生产圆钢的实践

介绍了用转炉冶炼40Cr钢的冶炼工艺、轧制工艺及所生产圆钢的材料性能.     

铜火法冶炼废水处理实践

阐述了铜冶炼火法工艺发展状况,剖析了铜冶炼过程产生废水的主要环节,并对废水处理工艺及原理进行了梳理,分析了某铜冶炼企业废水产生节点、产生特点和组成成分;针对现有的废水处理技术和资源化利用提出了合理的建议。特别阐述了阳谷祥光铜业自主研发的旋浮铜冶炼技术、粗铜自氧化还原精炼技术、平行流电解技术,硫化+石膏+中和”工艺和废水深度处理联合工艺特点,对采用火法冶炼工艺的铜冶炼企业的废水处理及资源化利用具有借鉴意义。     

倾动炉杂铜冶炼新型选渣熔剂的开发与研究

江西铜业集团公司贵溪冶炼厂(简称贵冶)对倾动炉杂铜冶炼工艺过程进行了一系列研究。针对杂铜冶炼原理、冶炼工艺及过程控制等展开一系列的摸索研究,使得倾动炉杂铜新型选渣熔剂的开发及应用得到成功,提升了倾动炉杂铜冶炼技术水平。     

硫系易切削钢的研发

通过对硫系易切削钢的冶炼工艺及轧制工艺进行研究,总结了硫系易切削钢生产时的冶炼工艺及轧制工艺控制要点．成功地开发了硫系易切削钢并形成批量生产。     

唐山不锈钢60万t不锈钢冶炼连铸工艺方案的确定

介绍了唐山不锈钢有限责任公司60万t不锈钢冶炼、连铸工艺方案的选择及主体设备的确定。该工艺路线采用高炉铁水冶炼不锈钢,具有冶炼成本低、钢水纯净度高等优点。     

锰矿烧结冷却工艺对烧结及冶炼的影响

本文从生产实际入手,介绍了冷却工艺对锰矿粉烧结及锰铁冶炼的影响;通过经济技术指标分析反映了冷却工艺对烧结及冶炼的效果,为烧结技术改造和强化高炉冶炼提供参考。     

梅山转炉试产生小结

根据梅山转炉试生产初期的冶炼情况，对冶炼工艺进行初步总结和分析，为寻求合适的脱磷、脱硫冶炼工艺，及日后生产提供借鉴和参考。     

提高韶冶ISP铅锌冶炼原燃料经济性途径的探讨

简单介绍了ISP铅锌冶炼工艺,分析了ISP原燃料成本状况及该原燃料条件下对工艺过程的影响,提出了提高ISP铅锌冶炼原燃料经济性的途径及相应的工艺措施。     

铁水预处理及转炉冶炼脱Ti实践分析

含有Ti的铁水对铁水预处理和转炉冶炼工艺均有不同程度的影响.为此,对含Ti铁水扒渣、脱Ti预处理及转炉冶炼等整个过程进行跟踪分析,从铁水分级扒渣、脱Ti预处理、转炉冶炼及出钢作业等方面提出了对含Ti铁水冶炼工艺的严格控制措施.     

镁热还原K2ZrF6制备镁锆中间合金

在KCl、NaCl熔剂的保护下,液态Mg能够还原K2ZrF6.通过控制炉料配比、还原温度、还原时间,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中间合金难以分离、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.     

外加物理场对激光熔化沉积内部缺陷控制

激光熔化沉积技术是基于“分层—叠加”原理,在高能激光束作用下、按照预定的路径,将同步送给的 金属粉末逐层熔化并快速凝固成形的先进制造技术,具有成形精度高、加工柔性好、内部组织均匀、力学性能 优异、适用难加工金属材料制备等优点,在航空航天等领域具有广阔的应用前景。但是激光熔化沉积过程中 容易产生未熔合、微裂纹、气孔等缺陷,限制了这项技术的大规模应用。其中,激光熔化沉积构件的微观组织 存在明显的各向异性,沉积过程中的快速加热和冷却使构件内部产生较大的残余应力从而导致其变形和开 裂。学者就如何改善激光熔化沉积构件的内部缺陷进行了广泛研究。因此,综述了通过在成形过程中外加温 度场、超声场、电磁场以及复合场的方法改善激光熔化沉积制件的内部组织和性能,以期为激光熔化沉积构件 综合性能的提高提供指导。     

Innovative Technology for Preparation of Seamless Nitinol Tubes Using SHS Without Forming

This paper presents innovative technology for the production of seamless Ni-Ti tubes using self-propagating high-temperature synthesis (SHS). The proposed production technology is a unique method which removes the need of forming operations, reduces machining processes, and at the same time it eliminates the negatives of production Ni-Ti alloys by conventional melting methods. The proposed process consists in SHS reaction in evacuated silica tube with the use of extremely high heating rate (over 300 K min^?1).     

浅谈铸铁熔炼技术

系统地归纳和分析了各种铸铁熔炼技术的现状、熔炼特性、冶金特性及其发展方向,为铸造企业合理选择工艺,提高产品质量提供借鉴。     

BN型易切削钢的冶炼工艺及其切削加工性

对BN型易切削钢的冶炼工艺与切削加工性进行了研究.通过实验室热态实验得到不同B、N元素含量的试样,利用理论计算研究试样中主要夹杂物的析出规律,然后对BN夹杂物的形貌、尺寸及组成进行分析,最后对试样进行力学性能测试及切削实验.结果发现在钢中添加B、N元素能够明显改善钢的切削性能,且不影响钢的力学性能.      

Electrical discharge machining

This article describes a laboratory technique of achieving the highest degree of passive fit of an implant-retained restoration using electric discharge machining (EDM). This process can save time by eliminating the need for conventional soldering procedures, increase the longevity of the restoration, and when used along with the clinical technique of fabricating a verification index, eliminate the clinical try-in phase.     

钛合金复杂构件等温锻造工艺研究

针对钛合金复杂构件采用机加工成形成本高,材料利用率低的现状,提出钛合金复杂构件的新工艺,即先等温锻造成复杂构件形状,然后辅以机械加工的方法成形。通过有限元模拟分析和实验研究,提出非对称变截面钛合金复杂构件等温锻造成形工艺为:锻造温度900～950℃,应变速率0.03 mm·s-1,采用玻璃润滑剂,模具材料选用K3合金和空冷的锻后处理。实验结果表明:采用该等温锻造成形工艺获得的钛合金复杂构件完全满足系统的性能要求,并可替代机械加工产品;按新工艺加工成形的钛合金复杂构件,不但降低成本,缩短机加工时间,而且材料利用率也提高到60%以上。     

钢铁半固态成形技术的研究进展和展望

低熔点合金半固态成形技术被专家称为21世纪新兴的金属制造关键技术。该技术已经成功地在商业领域中运行，人们一直在探索将此技术应用于钢铁材料。本文综述了钢铁半固态成形技术的研究开发过程，介绍了钢铁半固态成形的工艺、浆料的制备方法、半固态金属的微观组织演变以及对这种成形工艺的展望。笔者认为电磁搅拌制备浆料方法中的搅拌是无接触搅拌，更适用于高熔点钢铁材料。由于触变成形工艺本身的特点，使其更适宜于钢铁等高熔点材料的半固态成形控制。     

Integrated modeling for the manufacture of Ni-based superalloy discs from solidification to final heat treatment

Process models of the various stages of gas-turbine disc manufacture have been integrated to simulate the physical and microstructural transformations occurring within a nickel-based superalloy throughout the entire manufacturing route. Production of these critical rotating structural components requires several distinct processing stages: vacuum-induction melting (VIM), vacuum-arc remelting (VAR), homogenization heat treatment, cogging, forging, final heat treatment, and machining. During the course of these consecutive manufacturing stages, the various thermal and thermomechanical processes lead to significant changes in both the microstructural characteristics and internal stresses in the alloy. Although separate models have previously been developed to simulate the individual processing stages, this article describes how these models, which are explicitly expressed in terms of the initial and evolving microstructure, can be integrated to simulate the entire manufacturing process from secondary melting through to the final forging and heat treatment. The grain structure predicted for one stage is explicitly transferred as the initial conditions for the model, which simulates the grain evolution during the next step. This information also provides the basis of microstructure-explicit constitutive equations describing the material behavior. Industrial-scale manufacturing trials associated with the production of an INCONEL alloy 718 aeroengine turbine disc were used to validate the integrated model for grain size. The model also allows intrinsic or extrinsic defects entrained within the material during the initial solidification stage to be tracked through the subsequent processes. This provides a basis for calculating the areas of discs likely to be vulnerable to such defects and whether they might be removed during machining. It was shown that the microstructure of the alloy changes significantly throughout the process chain, the final microstructure and defect distribution at each stage being related to those formed in the previous stages. There was good agreement between the model predictions and experimental observations for both the intermediate and final processing stages. The implications of such integrated modeling for quality assurance through process control are discussed.     

Semi‐Solid Rheoforging of Steel

To produce steel components with complex shapes excessive machining is necessary frequently since high pressure die casting of steel is not industrially applied. Forming steel in the semi‐solid state can in principle produce new components and geometries which cannot be realised by conventional closed die forging. Semi‐solid forging of steel combines the possibility of producing geometries not conventionally forgeable in one forming operation and of adding further functions during the same operation. In previous investigations on thixoforming of steels, the semi‐solid steel was generated by reheating precursor material billets. An alternative approach for generating semi‐solid steel from the liquid state with subsequent forging operation is presented in this paper for the first time. The steel grades X210CrW12 cold work tool steel and 100Cr6 bearing steel are molten and driven into a globular semi‐solid state using a cooling slope and a cup. By cooling the steel into the semi‐solid range instead of heating it, the required process temperatures are lower than in the process route via heating. Therefore, the load on the dies in a semi‐solid forging operation is decreased. Suggestions for the respective layout of the process are made for both steel grades. Future potentials and challenges to be solved are discussed, showing advantages especially in the field of high melting point alloys such as steels. This technique enables to produce pre‐shaped semi‐solid billets to optimise the materials flow and the homogeneity of the mechanical properties.