The Effect of Sintering Temperature on Microstructure of High Chrome Bricks

The microstructure of high chrome bricks made at dif-ferent sintering temperature are analyzed by SEM. The re-sults indicate that the sintering temperature of high chromebricks has an optimum range, it is not the higher, the ber-ter. The high chrome. bricks made at this sintering temper-ature have the moderate crystal size in the matrix and ofdense structure. The closed bonding structure could be ob-tained between grains and matrix and no crackle occurred.The high chrome bricks with this microstructure have thebest dynamic properties.     

气化炉用后高铬砖的渣蚀机理

采用扫描电镜和XRD等分析方法,对石油焦气化炉和水煤浆气化炉用后高铬砖及渣蚀试验砖的显微结构进行了观察与分析。根据高铬砖显微结构变化,研究了在不同气化炉内高铬砖受熔渣侵蚀损毁的机理。结果表明:石油焦气化炉用高铬砖中的Cr2O3与熔渣中的V2O5接触反应,在低温下形成液相而被熔蚀,是其蚀损的主要原因;水煤浆气化炉用高铬砖蚀损的主要原因是Cr2O3在熔渣里的溶解和ZrO2的熔蚀;LIRR-HK95砖由于成分和结构的优化,抗石油焦渣侵蚀性能好。     

Discussion on Wear Mechanism of High Chrome Brick Used in Coal Slurry Gasifier

The microstructure and phase composition of high chrome brick used in coal slurry gasifier has been analyzed by means of SEM and Energy Spectrum. The results indicate that the used brick can be divided into different zones as slag-adhered zone, reaction zone, penetration zone and unaltered zone. The phase composition and microstructure are different and cracks occurred in different degree at these zones. A dense ring belt was formed with complex spinel ( Mg, Fe)( Cr,Al, Fe2O4) in the reaction zone near the hot face. The wear mechanism of the brick during its employment has been discussed. It is considered that the reaction and penetration of coal slag and strong reduetant bring about the composition change of the brick and destroys its original network inlayed structure and consequently result in its structure spalling and weakening strength, which is the main wear mechanism of the brick and followed by temperature fluctuation and high mechanical im-pact of flowing fluid with high-speed.     

水煤浆加压气化炉用高铬耐火材料的显微结构及损毁机理

采用扫描电镜和能谱分析方法 ,分析了水煤浆加压气化炉用高铬砖渣蚀前后的显微结构和相组成 ,探讨了主要损毁机理。结果表明 :煤熔渣与砖反应和渗透引起砖组成的改变 ,从而导致砖的结构剥落和强度弱化是砖损毁的主要原因 ;LIRR -HK90砖的显微结构呈网络状镶嵌结构 ,直接结合程度高 ,与渣反应可生成 (Mg ,Fe) (Al,Cr,Fe) 2 O4 复合尖晶石致密带 ,阻止了渣的进一步渗透 ,减缓渣蚀速度和结构剥落 ,其使用效果优于进口的同类产品     

Analysis of Spent High Chrome Brick in Slagging Gasifier

Wear of the spent high chrome brick in slagging gasifier was studied.The result shows that erosion and spalling are the main wear mechanism of high chrome brick and the CaO content of coal slag is crucial to wear of high chrome brick.     

水泥窑用低铬优质镁铬砖的研制

本文介绍了结合我国国情采用增铝、增铁的技术路线研制的低铬优质镁铬砖以代替普通镁铬砖，当Ｃｒ２Ｏ３＜４％时仍具有优良的热震稳定性和粘挂窑皮性。该砖已经在牡丹江水泥厂１＃窑烧成带使用了两个窑次，具良好有使用性能     

Chemical Corrosion Mechanisms of Magnesite-chrome Bricks by Converter Slag

The corrosion resistance of four kinds magnesitechrome bricks against converter salg was investigated by static crucible slag tests. The microstructures of the asdelivered and tested refractories were analyzed by means of SEM and EDS. The results showed that： Different magnesite-chrome bricks have different slag resistances. Generally, the slag resiantance sequence is as follows： rebounded fused magnesite-chrome brick 〉 semi-reboun- ded magnesite-chrome brick 〉 direct-bonded magnesitechrome brick 〉 silicate bonded magnesite-chrome brick. Slag reacts with the periclase of magnesite-chrome refractories, which results in the dissoving of periclase in fayalite slag. However, the complex spinels have superior slag resistance.     

铬砖在蓝色浮法玻璃液中的耐侵蚀机制

用广东石井特种耐火材料厂生产的铬砖(Cr2O3>94%)和洛阳浮法玻璃有限公司生产的蓝色浮法玻璃为实验材料,参照GB 1020488<玻璃熔窑用耐火材料在静态下抗玻璃液侵蚀实验方法>,使用扫描电子显微镜测试分析手段.研究了侵蚀前后铬砖显微结构和侵蚀界面附近元素组成的变化,探索了铬砖的耐侵蚀机制.实验结果表明:铬砖的耐侵蚀性与其显微结构有关,也与玻璃的组成有关,碱金属氧化物能降低其耐侵蚀性.     

Corrosion Mechanism of MgO-CaO Brick for AOD Furnace

In recent years burnt MgO-CaO brick have a-chieved a good application in AOD furnace[1].Thiswork analyzed the microstructure of residual MgO-CaObricks after being used in AOD furnace and discussedthe corrosion mechanism,which provides a theoreticalfoundat…     

再生废镁铬砖生产镁铬砖的试验研究

本文讨论当Cr2O3以电熔镁铬砂、铬铁矿及RH炉废镁铬砖3种形式引入并控制Cr2O3含量分别为6％、8％、12％和16％时,镁铬砖试样的各项理化性能.结果表明:加入废镁铬砖的试样的各项性能略低于加入电熔镁铬砂的试样,但与加入铬铁矿的试样相差不大,且其高温抗折强度均大于加入铬铁矿的试样.通过本试验说明,利用废镁铬砖生产的镁铬砖,可以替代直接结合镁铬砖,应用在水泥回转窑、有色金属冶炼及重烧镁砂竖窑等热工设备.     

烧成温度对高铬砖显微结构的影响

利用扫描电子显微镜分析了 170 0℃、174 0℃、1780℃、182 0℃和 186 0℃烧成后高铬砖的显微结构。结果表明 :高铬砖的烧成温度不是越高越好 ,而是有一个合适的烧成温度 174 0℃。在该烧成温度下制得的高铬砖 ,其基质中的Cr2 O3晶粒尺寸适中 ,基质组织结构致密 ,基质和颗粒结合紧密 ,无裂纹 ,并且其力学性能最佳。     

Study on Corrosion Mechanism Between MgO-CaO Refractories and Slag

1 IntroductionIn recent years, with the steady growth of steeloutput, the refinement process also became popular.The main processes include Argon-Oxygen Decarburi-sation ( AOD), Vacuum Oxygen Decarburisation(VOD), Secondary Refining Process〔1〕. No matte…     

AOD炉衬MgO-CaO砖的侵蚀机理

采用光学显微镜(OM)、扫描电镜(SEM)和能谱仪(EDAX)对AOD炉用镁钙砖的残砖进行了分析,探讨了炉衬镁钙砖的侵蚀机理。结果表明:AOD炉衬镁钙砖的蚀损主要是由硅酸盐液相的溶解和渗透引起的;在残砖反应带和原砖带之间形成的平行于工作面的横断裂纹,是加速镁钙砖损毁的重要因素。     

AOD炉渣对MgO-C砖的侵蚀机理研究

不锈钢生产主要采用氩氧精炼(AOD)炉冶炼工艺,本文探究AOD炉渣对钢包内衬用MgO-C砖的侵蚀机理,为提高钢包内衬用MgO-C砖的使用性能和服役寿命提供理论支撑。结合FactSage6.2软件、X射线衍射(XRD)、场发射扫描电子显微镜(SEM)和能量色散光谱(EDS)等测试手段分析炉渣侵蚀后MgO-C砖的物相变化、显微结构和化学成分变化。结果表明,随着侵蚀反应的进行,方镁石逐渐被熔蚀,且逐步出现Ca₃MgSi₂O₈等低熔点物相,以及MgAl₂O₄等高熔点物相。AOD炉渣通过基质部分侵蚀渗透MgO-C砖,并与方镁石反应生成Ca₃MgSi₂O₈等低熔点物相,熔蚀方镁石;同时,方镁石边界处生成MgAl₂O₄,阻碍AOD炉渣对MgO-C砖的侵蚀渗透。     

大型合成氨装置及炉衬用耐火材料

介绍了引进的以天然气、渣油和煤为原料的大型合成氨装置的工艺原理、炉型选择和炉衬耐火材料。同时介绍了气化炉用各种耐火材料国产化的进展情况，以及耐火材料的损毁机理。     

一种新型微裂纹镀铬工艺及镀层性能研究

本文研究了电镀微裂纹硬铬的工艺参数和添加剂对镀层裂纹长度、深度和密度的影响。借助3D显微镜以及SEM观察镀层表面微裂纹,并将自行研发的ND-331微裂纹镀铬工艺与标准镀铬工艺、国外知名品牌的HCR镀铬工艺进行了对比。结果表明,研发的ND-331微裂纹镀铬工艺电流效率可达20.5%,镀铬层裂纹密度为1020条/cm、硬度为989.9 HV,其性能优于标准镀铬,与HCR镀铬相当。     

炼铜转炉用镁铬砖损毁机理的探讨

研究了炼铜转炉用直接结合镁铬、硅酸盐结合镁铬砖的损毁机理。结果表明：对直接结合镁铬砖而言，不论是其抗冰铜的渗透性、抗转炉渣的侵蚀性，还是热震稳定性、高温强度均优于硅酸盐结合镁铬砖。所以使用直接结合镁铬耐火材料替代硅酸盐结合镁铬耐火材料可以大幅度地提高转炉炉龄。     

德士古气化炉耐火砖的选型、施工和应用

德士古气化炉耐火砖的使用寿命关系着整个系统是否能够长周期、安全、稳定运行.从德士古气化炉的耐火砖的选型、施工、应用等方面进行分析,旨在找出气化炉耐火砖的最佳运行方式.     

炼铜诺兰达炉用镁铬砖损毁机理的探讨

简要介绍了诺兰达炉用耐火材料的现状,并以风口区使用后的镁铬残砖为试样,采用化学分析、SEM和EDAX等手段对其侵蚀机理进行了分析研究。结果表明:铜渣对镁铬耐火材料的侵蚀,在工作面以熔蚀为主;在砖体内部主要以锍渗透为主。锍渗透的主要途径为开口气孔、晶界及微裂纹。