共查询到20条相似文献,搜索用时 78 毫秒
1.
Philippe Guillo José Simões 《钢铁》2004,39(Z1):93-97
在浇注相同的钢种时,钢水的可浇铸性经常会由于一些不明原因出现波动,诸如水口堵塞,正常浇铸或对连铸耐材产生侵蚀.本文分析了钢水中杂质含量的高低如何对夹杂物组分和耐火材料侵蚀产生影响. 相似文献
2.
3.
4.
氧化锆陶瓷泡沫过滤器,除了减少水口阻塞和提高钢水洁净度,减少了结晶器液面突然波动引起的事故,还改进了中间包流体动力学。 相似文献
5.
连铸用的铝碳质和铝锆碳质长水口砖为实现连铸钢水罐和中间罐之间的钢水流股的密封浇铸,国外一些耐火材料生产厂家开发成功了连铸用的铝碳质和铝锆碳质的长水口砖.连铸中间罐用的长水口用高纯度原料制成并用等静压机成型.长水口砖经高温隧道窑烧成后,要在车床上加工到... 相似文献
6.
一、前言众所周知,弧型连注机浇铸的铸坯,由于夹杂物在接近铸坯内弧侧表层的聚集,降低了连铸方坯的内部质量。为了减小冲击深度,防止夹杂物的聚集,已设计出了浸入式水口。然而,由于钢水的侵蚀和操作条件的限制,水口的形状易于改变。因此,为容易地得到高质量的方坯,研制并试验了用电磁搅拌器促使钢水流动的方法。 相似文献
7.
8.
(1)水口砖的改善原设置400mm见方两种水口:一是吹气用多孔塞(即BB水口);二是浇钢水口(即SN水口)。改进措施:一是将方形砖改成圆形砖;二是将成砖工艺改为真空振动浇注成形;三是适当调整了耐火材料组分,即将原来的两种水口及不同材质调整为一种(铝镁质)材质,具体成分为91%Al2O3、0.5%SiO2、8%MgO,各种物性指标也相应改善。使用结果表明,改进后砖不易产生裂纹,且致密性能、耐氧气清洗性能优良。(2)钢包内衬结构的改善内衬渣线部比接触钢液部更易熔损,故选用了进口镁铬质砖砌筑渣线。进口砖的化学组成为69.7%MgO、12.4%Cr2… 相似文献
9.
水口结瘤一直是困扰连铸生产的问题,对连铸生产中发生结瘤的中间包上水口和浸入式水口从上到下做了全面的解剖分析,通过SEM、EDS、X-RD等手段对水口的结瘤物进行分析研究。结果表明,中间包上水口结瘤严重,钢水完全凝结;在浸入式水口渣线以上,发生了严重的结瘤,厚度约为16 mm,渣线下的结瘤较轻,结瘤物主要是Al2O3夹杂着钢水凝结而成,由于钢水中的酸溶铝含量较高,水口处Al2O3的富集使钢水凝结,堵塞水口。根据研究得出,中间包上水口和浸入式水口结瘤堵塞的原因为钢水酸溶铝含量较高,钢水在水口处温降过大、拉速过低等。 相似文献
10.
11.
Interfacial reaction between refractory materials such as zirconia, magnesia and doloma brick, and the metallurgical slags of the CaO‐SiO2‐MgO‐CaF2 system with varying CaF2 content were investigated at high temperatures using various methodologies with static and dynamic modes. To figure out the corrosion mechanism due to interfacial reaction with the slag, the slag characteristics were examined in terms of flow temperature and viscosity and the corroded interface of zirconia, magnesia and doloma refractories were analyzed by SEM‐EDS and EPMA. With an addition of CaF2, three different layers were formed at the interface between slag and zirconia refractory. Furthermore, the corrosion of zirconia refractory was found to be accelerated with an increase of CaF2 which facilitated the dissolution of intermediate compounds. The penetration of slag through the grain boundaries of MgO refractory is enhanced by increasing the content of CaF2 due to an increase in the fluidity of slag in the dynamic mode. On the other hand, in the static condition, a dense Ca2SiO4 layer is formed at the hot face of magnesia‐doloma refractory due to a reaction between silica in slag and lime in doloma, resulting in the protection of direct corrosion of refractory brick. However, the thickness of C2S layer decreases with increasing content of CaF2 due to an increase in fluidity of slag. 相似文献
12.
对钢包供气砖的供气形式、结构、性能及使用后蚀损情况进行分析讨论,提出了提高使用寿命与吹成率的新型供气砖的设计方法。 相似文献
13.
ABSTRACTThe process parameters of selective laser melting (SLM) fabricated 24CrNiMoY alloy steel were optimised. Different contents of zirconia powder were added to the 24CrNiMoY alloy steel powder. With the optimum process parameters, the fabricated samples were characterised using various modern analysis methods. The results show that the main phase composition of 24CrNiMoY alloy steel is proecctectoid ferrite (PF) and granular bainite (GB). After the addition of zirconia, Lath bainite (LB) begins to appear, and with the increase of zirconia, the content of LB first increases and then decreases. When the zirconia content is 0.3%, the average micro hardness of the 24CrNiMoY alloy steel reaches the maximum and is 374?HV. In addition, the tensile strength is 811?MPa, the elongation is 6.7%, and the fracture surface shows ductile fracture. 相似文献
14.
摘要:首先,总结了3种常用的非金属夹杂物对不锈钢耐点蚀性能影响的研究方法,即原位腐蚀观察、微区电化学法、原子力显微镜。其次,总结了硫化物、氧化物、稀土夹杂物3种不同类型夹杂物对不锈钢耐腐蚀性能影响。随着硫化物含量的增多,不锈钢的耐点蚀性能会下降;对于氧化物的影响,目前的研究集中在氧化物的成分对不锈钢耐点蚀性能的影响。不同成分的夹杂物对不锈钢耐点蚀性能的影响机制还不是很清楚;稀土夹杂物对不锈钢点蚀的影响主要与稀土对不锈钢中夹杂物改性有关。而后,汇总了目前提出的夹杂物对不锈钢耐点蚀性能影响的机制,即贫Cr区机制、微缝隙机制、活性机制。贫Cr区机制主要用于解释硫化物引起的点蚀,后2种主要用于解释氧化物引起的点蚀。最后,提出了夹杂物控制提升不锈钢耐点蚀性能的展望。 相似文献
15.
16.
对高炉炉缸用炭砖及刚玉砖的抗渣侵蚀性及挂渣性进行了研究。在1 500 ℃高温条件下进行试验,探究现场高炉渣对炭砖及刚玉砖的侵蚀机理,通过SEM-EDS及XRD等手段分析侵蚀界面的微观组织结构和物相组成,并提出炭砖及刚玉砖挂渣理论。试验结果表明,高炉渣与刚玉砖在侵蚀界面发生反应,反应生成的镁铝尖晶石及刚玉砖中的Al2O3、SiC等高熔点物质阻碍高炉渣对刚玉砖的进一步侵蚀;高炉渣在炭砖表面未生成高熔点物质,炭砖因与高炉渣黏结点少而导致高炉渣对炭砖黏结强度差,从而形成炭砖表面渣皮周期性脱落。 相似文献
17.
18.
连铸机拉矫辊辊面激光重熔纳米ZrO2基涂层性能 总被引:1,自引:0,他引:1
为了提高连铸机拉矫辊的使用寿命,在H13钢表面等离子喷涂常规级和纳米级两种规格的ZrO2涂层,并对其进行激光重熔处理。利用有限元软件ABAQUS分析热障涂层对拉矫辊温度场的影响,利用激光共焦显微镜观察涂层表面和断面的组织结构,利用场发射扫描电子显微镜(SEM)测量涂层断面的元素分布,采用Gleeble-3800热模拟试验机考查涂层的抗热冲击性,结果发现,经激光重熔之后纳米级ZrO2涂层的孔隙率和微裂纹数量都明显少于常规级ZrO2涂层,并且纳米级ZrO2涂层的抗热冲击性都优于常规级涂层。 相似文献
19.
20.
A pure TRIP‐steel alloy and a novel zirconia reinforced TRIP‐steel matrix composite were implemented in a 2D square‐celled honeycomb structure fabricated by a paste extrusion method, respectively. In terms of a series of compression tests in out‐of‐plane loading direction the buckling and the pronounced strain hardening behavior of the honeycomb structures are described with regard to different material compositions and varied nominal strain rates. Both the compressive flow behavior and the microstructure evolution in the crushed zones are controlled by the rate of formation of strain‐induced martensite and the ceramic particle/steel matrix interactions. The insertion of magnesia partially‐stabilized zirconia (Mg‐PSZ) particles in the austenitic steel matrix cause an increased yield strength and higher compression stresses up to certain deformations degrees. The limited ductility of the composite materials is a consequence of the rearrangement and fracture of zirconia particles initiating cracks and shear bands during deformation. Consistently, the visible strain rate effects on the mechanical responses of the honeycomb structures are similar to AISI 304L austenitic stainless steel specimens in the form of compact rods. However, at high local strain rates generated in drop weight impact tests a micro‐inertia factor support the failure behavior of the cellular structures. 相似文献