电镀锌耐指纹板黑斑缺陷的研究

运用扫描电镜对电镀锌耐指纹板表面黑斑处缺陷的成分、形貌进行了测试,分析了该缺陷产生的原因及形成机理。研究结果表明:黑斑形成于电镀过程,缺陷处存在碳、氧等异常元素,导致电镀过程中镀锌不良,局部漏镀,从而锌层易被氧化变黑。     

耐指纹电镀锌板表面亮点缺陷分析

采用扫描电镜对耐指纹电镀锌板上表面亮点缺陷形貌及成分进行了分析,对其形成机理进行了探讨。结果表明:泄漏在电镀槽镀液中的少量硅藻土以杂质形式吸附在基板表面,影响电镀过程锌层晶体形核及生长形态,形成尺寸大于正常部位且平行于基板的片状晶体,从而导致耐指纹电镀锌板上表面产生亮点缺陷。     

电镀锌耐指纹板冲压开裂原因分析

针对偶发于电镀锌耐指纹板上无法通过调整模具进行改善的冲压开裂现象,分析了原因。通过对材料成分、工艺和性能反查,对比分析电镀锌基板和电镀锌材料样板的力学性能和表面粗糙度,认为更换新钝化液导致了电镀锌耐指纹板表面钝化膜的化学成分发生变化,影响了成品材料的表面粗糙度和摩擦系数,最终对冲压性能造成影响。更换钝化液后,冲压开裂问题得到解决。     

马钢建筑用热镀铝锌有铬耐指纹彩涂板的试验研究

基于马钢彩涂生产工艺,开展了彩涂热镀铝锌有铬耐指纹板的试制,并通过耐碱性和耐腐蚀性等试验方法对三家供应商提供的有铬耐指纹板进行试验分析。结果显示,马钢彩涂生产线基本掌握了热镀铝锌有铬耐指纹板的生产工艺技术,并且通过试验分析优选出一家最适合的耐指纹液供应商。     

热轧热镀锌板表面划伤原因浅析

分析了带钢在镀锌过程中,镀前、镀中、镀后三阶段产生划伤的原因,并从板材原料、张力设置、锌液温度和化学成分、人为操作等方面人手,提出解决措施.措施实施后,热轧热镀锌板表面划伤大幅下降,涂镀划伤和镀后划伤基本杜绝,表面划伤缺陷所占总缺陷比重也由50.2%降低到了11.6%.     

X射线荧光光谱法测定镀铝锌板耐指纹膜重

1前言镀铝锌钢板表面再进行耐指纹处理后,赋予了镀铝锌层表面优良的耐指纹特性和良好的耐蚀性、耐热性、导电性等。冷轧板厂生产两种类型的耐指纹钢板,一种是无Cr（VU耐指纹型,应用的是以Zr盐为主的耐指纹液;一种是有Cr（VI）耐指纹型,应用的是传统含Cr（VI）钝化型耐指纹液。     

热镀锌工艺对汽车用镀锌钢板表面缺陷的影响

用扫描电镜和能谱分析研究了热镀锌板(%:0.001 5C、0.004P、0.005S、0.02A1、0.04Ti)表面平行的条状凸起缺陷,得出镀锌层表面有黑斑、微裂纹、贝壳状花纹、划伤痕迹及氧化皮等缺陷。分析表明,锌液中Sb含量偏高,增加锌层脆性;锌液中Al含量偏高,锌液温度低,以及镀锌前钢板划伤和氧化铁清洗不完全导致产生表面缺陷。     

涂镀钢铁产品发展近况

随着带钢生产技术的日益进步,涂镀钢铁产品已由传统产品向具有高性能的新型产品发展,无铬钝化板、氟碳板、耐指纹板及自清洁板等应运而生.介绍了部分涂镀钢铁产品近期发展的概况,指出在发展过程中需要注意并加以解决的一些问题.     

涟钢高端热镀锌无铬耐指纹产品开发与应用

本文通过对无铬耐指纹药剂配方优化、无铬耐指纹产品膜厚、生产运行速度等研究与控制,涟钢生产的无铬耐指纹产品具备比较优异的表面电阻、高温耐黄变、烤漆性能、耐蚀性能等性能;同时解决了表面偏暗、条锌、云状等表面缺陷,研发出的无铬耐指纹产品满足电子电器行业高表面质量的要求。     

攀钢环保镀锌板技术突破欧盟壁垒

正2月26日,笔者从攀钢研究院材料研究所冷板实验室获悉,攀钢成功开发出无铬耐指纹处理液,并生产出了无铬耐指纹热镀锌板等产品。据介绍,为防止钢板在储存及运输过程中产生锈蚀,需对钢板表面进行短期防腐处理,传统的做法是采     

Microstructure of W - Ni - Sn Composites in Relation to Amount of Liquid Phase on Sintering

Microstructure transformation is examined for W - Ni - Sn composites made by liquid-phase sintering at 1200 °C for 1 h; the liquid phase was a eutectic containing 67.5 mass% Ni and 32.5 mass% Sn. There is a nonmonotone dependence of the tungsten grain size in the sintered composites on the volume proportion of liquid phase in the range 6.7–36.8%. The mean grain size in relation to volume proportion of liquid phase in liquid-phase sintering is calculated from rheological sintering theory. The form of the empirical function f(v) is quantitatively demonstrated, which determines the rate of tungsten grain growth on liquid-phase sintering and is dependent on the proportion of matrix in the composite and the size of the liquid phase layer. __________ Translated from Poroshkovaya Metallurgiya, Nos. 7–8(444), pp. 53–57, July–August, 2005.     

降低转炉钢水终点碳氧积技术实践

延长转炉复吹炉龄一直是钢厂追求的目标,其中转炉钢水终点碳氧积又是衡量底吹效果的一个重要指标。降低钢水终点碳氧积既可提高合金收得率,又可提高钢水质量。     

零星废液达标治理实践

介绍了企业生产环节中少量废液的来源,和防治对策,并较详细地论述了以废治废的简易处理方法。     

Inclusions in continuously cast steel slabs - numerical model and validation

A numerical model for liquid steel flow and inclusion transport and separation in continuous casting moulds is presented, which covers several features simultaneously. The free surface at the meniscus is computed; the submerged entry nozzle is discretised in detail to resolve the outlet geometry; gas injection through the SEN and its effect on liquid steel flow are considered; capture of inclusions within gas bubbles is covered in a simplified approach; the solidifying shell and the process of inclusion entrapment by the growing shell are simulated. Computed flow profiles are compared to experimental results on water and to measurements on liquid steel in a slab caster. Predicted inclusion profiles in solid slabs are compared to empirical findings from literature. Results of the model for various cases will be presented in a subsequent publication.     

COREX-3000发生煤气管堵塞物的分析

宝钢COREX-3000是世界上规模最大的COREX熔融还原炼铁装置。熔融气化炉的发生煤气管（GGD）堵塞是实际生产中遇到的重大问题之一。通过对COREX-3000发生煤气管堵塞物进行取样,并在实验室中采取多种手段对其化学成分、理化特征等进行分析,结果表明,堵塞物呈明显的层状结构,由大量液相包裹铁颗粒构成。堵塞物试样在1 000～1 100℃开始软化收缩,而在1 250～1 300℃产生明显液相。     

The precipitation diagram of [Ce]-[O]-[S] in liquid iron and its application

A space precipitation diagram of [Ce]-[O]-[S] in pure liquid iron has been constructed utilising recent experimental thermodynamic data gathered on allied equilibrium systems of RE-O, RE-S and RE-O-S. A quantitative correlation between the activities of oxygen, sulphur and the constitution of the formed RE inclusions has been found. This correlation was theoretically evaluated through thermodynamic calculation and verified by experimental data concerned with the activities of oxygen and sulphur in liquid iron and the composition of the formed RE inclusions.     

广钢实施GB1499—1998标准的统计分析

广州钢铁股份有限责任公司实施标准GB1499－1998以来,电炉厂质量稳定,至今未出现力学性能的废品;比实施前减少了吨钢合金的加入量（其中Mn含量平均降低0.235%）,因Cu超标而产生的原料钢炉数也逐步下降,有利于冶炼成本降低;而转炉厂初期出现多炉成分偏低,屈服、抗拉强度不足的钢铁废品,经过及时的调整（提高钢水的C、Mn成分,加强钢水的均匀性）,质量逐步稳定,基本达到预期的效果。     

Thermodynamics of Liquid Alloys and Metastable Phase Transformations in the Copper - Titanium System

We have used solution calorimetry at temperatures of 1573 K and 1873 K over broad concentration ranges to study the mixing enthalpy of Cu - Ti liquid alloys. The molar mixing enthalpies of the system are significant negative values. We have established the temperature dependence of the molar mixing enthalpies of the system: there is an increase in their exothermicity as the temperature is lowered. The significant negative mixing enthalpies of the system allow us to conclude that the chemical bonds are localized in the studied melts and consequently associates form. We tested this conclusion within ideal associated solution theory, which describes well the results obtained with a set of CuTi and CuTi₂ associates. Using the model obtained, we have calculated the excess thermodynamic functions of mixing (enthalpy, Gibbs free energy, heat capacity) for the liquid alloys. We estimated the Gibbs energies of fcc, bcc, and hcp solutions in the system by the CALPHAD method, using data from the initial sections of the phase diagrams and from the corresponding thermodynamic data. We have calculated the metastable phase equilibria between the limiting solid solutions and the liquid or supercooled liquid phase. It was shown that for the supercooled liquid and the amorphous phase, a broad concentration range of relative thermodynamic stability can be obtained. The concentration range of amorphization of Cu - Ti melts corresponds to the position of the metastable liquidus line and the T₀ line at temperatures close to the temperature range of amorphous solidification. __________ Translated from Poroshkovaya Metallurgiya, Nos. 5–6(443), pp. 67–80, May–June, 2005.     

Density of Liquid Steel over Temperature Range of 1 803-1 873 K

The density of three kinds of liquid steel was measured by a modified sessile drop method over the temperature range of 1 803-1 873 K. It is found that the density of liquid steels decreases with increasing temperature and carbon content in steel. Both of the density and its absolute temperature coefficient of studied steels are smaller than the literature values of pure iron. The molar volume of the steels increases with increasing temperature.     

Nature of the strength of tungsten - nickel - iron alloys

Conclusions A study was made of the structural changes taking place in W - Ni - Fe alloys during slow cooling from the sintering temperature. It is shown that aging occurs in the binder phase and in a layer of the refractory tungsten-base phase adjoining the low-melting-point constituent.A W - Ni - Fe alloy sintered in the presence of a liquid phase and slowly cooled from the sintering temperature has a complex multiphase structure of a dispersed-aggregate type. The results of the present investigation provide a foundation for subsequent research into the behavior of the phase constituents of these alloys during plastic deformation and into the nature of their strength.Translated from Poroshkovaya Metallurgiya, No. 5(65), pp. 73–78, May, 1968.