Microalloying of manufacturing steel with vanadium and nitrogen

The influence of microalloying with nitrogen and also vanadium and other nitride-forming elements on the properties of manufacturing steels is systematically analyzed. In rolling specialized components, thanks to decrease in austenite grain size, dispersional hardening by nitride nanoparticles, and the formation of improved substructure, the steel has distinctive properties: 30–50% increase in strength with excellent plasticity and resistance to fatigue and brittle failure. Principles are outlined for controlling the properties of steel in different components without quenching, with a view to replacing traditional nickel steels. Examples of the applications of microalloyed steels are presented.     

Microalloying of structural steel with nitride-forming elements

Attention focuses on why microadditions of titanium, zirconium, and aluminum in structural steels that will undergo vanadium-nitride hardening and standard heat treatment prove ineffective. Parameters that characterize the effectiveness of nitride (carbonitride) hardening of steel are identified.     

Microalloying of steel with boron and the development of ferrotitanium boride

The smelting of steel microalloyed with boron is considered; the composition of the boron-bearing alloying additives is analyzed. Experience in the production of new boron-containing alloying composites by self-propagating high-temperature synthesis is described. The main aspects of self-propagating high-temperature synthesis in the Ti-(Fe-B) system are studied. Industrial test data for ferrotitanium boride, which is an alloying additive produced by self-propagating high-temperature synthesis, are presented for the smelting of 40γP steel.     

钢铁炉窑协同处置冶金及市政难处理固废技术路线

 无害化和资源化仍然是当前固废处置的重要方向,尤其在当前全力实现“碳达峰、碳中和”目标的大背景下,“以废代碳”还是降低碳排放的重要途径。针对当前固废处置出现的处置成本高、资源化利用不充分、邻避效应严重的现状,提出了利用钢铁炉窑,特别是烧结球团工序协同处置冶金及市政难处理多源固废的思路,提出了建立多源固废物质属性、能源属性、毒害属性多维识别指标体系与最佳处置路径的生态化适配原则;基于钢铁工业窑炉特性及固废属性,构建了火法/湿法预处理耦合热工制度优化的冶炼主工艺协同处置固废的技术路线,及基于北斗-物联网的区域性固废协同处置智慧平台,为冶金及市政固废生态化协同处置提供方向指导和技术参考。     

Deoxidation and modification of rail steel

Ukrainian Scientific Research Institute of Metallurgy (UkrNIImet). Nizhniy Tagil Metallurgical Combine (NTMK). Ural Scientific-Research Institute of Metals (UralNIIChM). Translated from Metallurg, No. 1, p. 28, January, 1990.     

Extracting noble metals from industrial solutions and waste waters with biosorbents

The chemical composition of various industrial solutions of the Shchelkovo Plant of Secondary Noble Metals is evaluated. It is established that the excess content of heavy metals with respect to gold and silver is larger by a factor of more than 1000. The microbial biomasses of various systematic groups are approved for extracting Au and Ag from solutions with a high salt background. The appropriateness of selectively extracting heavy metals from such complex solutions is shown. The behavior of heavy metals is investigated for sorption on biosorbents from individual solutions within the pH limits of 1.0–6.0 for the medium. The decisive significance of the pH of the solution (within the limits 1.0–3.0) on selectively extracting Ag from industrial solutions is determined. The notion that silver and heavy metals are attributed to different groups of metals by varying the degree of sorption with microorganisms, depending on the pH medium, is confirmed. The specific behavior of the biomass cells in the acidic medium also promotes the separation of these elements. Testing the biosorbed extraction of silver from the industrial solution on a granulated lincomycin biomass is approved under industrial conditions. The average degree of extraction was Cu ≤ 8.1, Ni 4.2, Zn 4.0, Fe 15.5%. The losses of biosorbent are about 70 g/m³ of the solution.     

工业废水中金属元素的测定

工业废水中金属离子对水环境造成污染,并危及人体健康,应准确进行测定.论述了原子吸收分光光度法测定工业废水中金属元素的原理,重点论述了测定Zn的条件、范围、干扰等因素,总结了测定锌的条件及测定结果;实验证明,用原子吸收分光光度法测定工业废水中的Zn元素,可取得较好的结果.     

Interaction of alumina inclusions in steel with calcium-containing materials

Clogging of tundish and submerged entry nozzles (SENs) adversely impacts productivity and quality in the continuous casting of aluminum-killed steels. Clogging results from an accretion layer that develops on the inside surface of the nozzle and restricts steel flow. Current nozzle refractories often react with molten steel to form solid by products that promote clogging. Nozzle materials that are inert with the liquid steel or react with accretions to form liquid reaction products could inhibit or eliminate clogging. Static experiments were conducted to investigate the stability between calcium-based materials and aluminum-killed steel. The results indicate that both calcium titanate and calcium zirconate react with alumina to form calcium aluminates. However, only the reaction between alumina and calcium titanate yielded calcium aluminate chemistries that were molten at steel casting temperatures. Liquid reaction products are preferred since they would be removed from the nozzle by the steel flow, thereby preventing accretion formation and clogging.     

碳钢及耐候钢在模拟工业大气环境中的腐蚀性能研究

通过周期加速腐蚀试验研究了碳钢Q345B和耐候钢S450EW在模拟工业大气环境中的腐蚀规律。采用失重法对试样的腐蚀速率进行分析,发现Q345B钢的腐蚀速率高于S450EW钢。利用电化学交流阻抗技术(EIS)对锈层的电化学特性进行分析,Q345B钢的锈层电阻随着时间的延长逐渐降低,S450EW钢的锈层电阻随着时间的延长逐渐增大,并且S450EW钢的锈层电阻明显高于Q345B,即S450EW钢的锈层对腐蚀介质的阻滞性能更为优异。通过扫描电镜(SEM)及X射线衍射(XRD)对锈层进行分析,发现S450EW钢的锈层含有更多的α-Fe OOH,锈层更为致密,能为基体提供更好的保护。     

钢铁工业的空气消耗与废气排放

 基于工业系统与环境之间的物质交换,建立空气是冶金资源的概念,阐述了钢铁工业空气消耗量、废气产生量、污染物排放量三者间的联系及其对区域大气环境质量的影响。调研核查了若干家钢铁企业,统计其烧结、炼焦、炼铁、炼钢和轧钢等各生产工序,以及高炉-转炉流程、全废钢-电炉流程的空气消耗量和废气排放量。以吨钢为计算基准,给出了中国钢铁工业的资源消耗结构和废物排放结构以及空气消耗和废物排放数据,其中吨钢空气消耗量（以质量计）占吨钢资源消耗总量的85%以上,强调了减少空气消耗和废气产生量对降低污染物排放总量、改善区域大气环境质量的重要性。列举了富氧乃至纯氧燃烧、废气循环再利用、烧结矿竖式冷却换热技术的节能减排案例,指明应用这些关键技术、优化钢铁生产流程和发展全废钢电炉短流程等是大幅度减少空气消耗和废气产生量,进而减少颗粒物、SO₂、NO_x排放量的有效途径。     

Thermodynamics of steel modification by barium and cesium alloys

On the basis of experimental, production, and literature data, appropriate parameters for the theory of subregular ionic solutions are determined. Solubility surfaces for the components are plotted, for low-alloy and carbon steel and also for multicomponent alloys.     

Electric-spark alloying of steel with heterogeneous molybdenum-containing zirconium nitride materials

Conclusions A study was made of the possibility of employing ZrN-Mo composites as materials for ESA electrodes. It is shown that the erosion of such a composite cathode decreases with rise in the Mo content of the material. The process of strengthened layer formation is affected not only the by particle size distribution of the erosion products but also by their phase composition. The formation of volatile oxides has a deleterious effect on the surface strengthening process. The best characteristics — a high degree of continuity, large thickness, close contact with the basis material, and strong adhesion to it — are exhibited by the layer forming during ESA with a 40 vol.% ZrN + 60 vol.% Mo composite electrode. During electric-spark processing a redistribution of carbon takes place in the surface layers of the cathode, the highest carbon concentration being reached in the white layer, and the ferrite grain decreases in size and changes in shape.Translated from Poroshkovaya Metallurgiya, No. 6(210), pp. 57–61, June, 1980.