钢厂
凝固速率对定向凝固50W600无取向硅钢固液界面稳定性和枝晶间距的影响
采用ZMLMC超高梯度定向凝固装置,研究了5种凝固速率(10、35、80、150和450μm/s)对定向凝固50W600无取向硅钢的固液界面稳定性转变规律和一次、二次枝晶间距的影响。研究结果表明,在特定的温度梯度下,随着凝固速率的增加,定向凝固的固液界面由胞状晶转变为胞状枝晶,再转变为细小的树枝晶。随着凝固速率的增加,定向凝固组织的枝晶形貌逐渐细化,一次和二次枝晶间距逐渐减小,且与冷却速率之间都符合指数关系:λ1=151.73×(G L·R)-0.31,λ2=22.07×(G L·R)-0.44。当冷却速率达到4.275℃/s时,一次、二次枝晶间距分别为112μm、14.1μm。 Under the conditions of certain temperature gradient and different solidification rate,the directional solidification experiment of non-oriented electrical steel 50W600 was carried out.The microstructure of 50W600 steel was also analyzed in different solidification rate.The result shows that the solid/liquid interface of the steel undergoes an evolution from cellular,cellular dendrite and finally to fine dendrite morphologies.The dendrite refines gradually and the distance between dendrites decr...
硅钢铸坯再加热过程中夹杂物的析出行为
研究了硅钢铸坯再加热过程中夹杂物的析出行为。采用非水溶液电解提取+扫描电镜观察方法,观察了试样的显微组织,统计了夹杂物的尺寸、种类、数量、分布。结果表明,均热温度为1 523 K时,水淬试样的夹杂物尺寸绝大部分小于0.5μm,0.5~5.0μm的夹杂物数量很少,没有发现5.0μm以上的夹杂物。此外,均热时间为10、30、60、90、120、240 min时,对应试样中0.05~0.2μm的夹杂物数量分别为4.04×104、4.73×104、3.70×104、3.33×104、3.10×104、1.56×104个/mm3。绝大部分夹杂物以MnS、AlN、CuxS类为主,并以三类夹杂物中的两类复合或三类复合居多。三类复合夹杂物总量占每组试样夹杂物总量的90%或以上。随均热时间延长,典型的夹杂物组成会发生如下变化:MnS+AlN+CuxS MnS+AlN AlN。与此同时,MnS、AlN、CuxS三者复合比例从45.2%(均热10 min)降为9.7%(均热240 min)。 The methods of electrolysis extraction from nonaqueous solution and scanning electron microscope were adopted to study the precipitation behavior of non-metallic inclusions in Si steel slabs during reheating processes.The morphologies,chemical compositions,quantity and size distribution of non-metallic inclusions in these steel samples were analyzed.Results show that,when the soaking temperature is 1 523 K,almost all of the non-metallic inclusions are smaller than 0.5 μm,few are in the range of ...
退火温度对双辊连铸无取向硅钢组织的影响
利用光学显微镜、TEM和EBSD研究了退火温度对双辊连铸无取向硅钢再结晶组织的影响。结果表明,900℃退火后组织分布不均匀,有大量带状组织,平均晶粒尺寸29.5μm。提高退火温度,晶粒尺寸增大,组织均匀化程度增加,1050℃退火时,带状组织基本消失,平均晶粒尺寸42.2μm。 Effect of annealing temperature on recrystallization microstructure of non-oriented electrical steel produced by twin-roll casting process was investigated using OM,TEM and EBSD.The results show that the recrystallization microstructure is uneven because of many banded grains existing,average grain size is 29.5 μm.With annealing temperature increasing,the recrystallization grain size increases,microstructure becomes more homogeneous.When 1050 ℃ annealing,the banded structure almost disappear and...
本钢无取向硅钢热轧生产工艺路线的实践
冷轧无取向硅钢是高技术含量、高附加值产品,工艺复杂,生产周期长,过程控制难度大,被誉为钢铁产品中的\"工艺品\"。热轧生产工艺又是无取向硅钢生产的重中之重,直接决定了硅钢的铁损和电磁性等多项指标。 Cold rolled non-oriented silicon steel is high technology content 、high added value product. Its process is complex, its production cycle is of length, and its process control is difficult, which is known as the iron and steel products \" Arts and crafts\". Hot rolling production process is the top priority of non-oriented silicon steel, which directly determines iron loss of the silicon steel and electromagnetic property,as well as other many index.
ICP-AES法测定硅钢中铌的不确定度评定
分析了电感耦合等离子体发射光谱法(ICP-AES)测定硅钢中铌的检测过程,讨论了该检测过程中不确定度的主要来源,建立了该方法的定量的数学模型,并根据这一模型计算出了检测结果的合成标准不确定度和扩展不确定度。 The measurement of niobium content in silicon steel by inductively coupled plasma atomic emission spectrometry(ICP-AES) was analyzed,by which the main factors affecting the uncertainty of the measurement were ascertained and the calculation formula was given.Finally,according to the formula the combined uncertainty and expanded uncertainty were obtained.
210 t BOF-RH-CC炼钢过程无取向硅钢XG800WR洁净度的试验研究
两炉次无取向硅钢XG800WR(/%:0.003~0.004C、0.71~0.75Si、0.32~0.33Mn、0.004~0.007S、0.016P)的炼钢流程为铁水预处理(KR)-210 t顶底复吹转炉-钢包吹氩-RH脱碳精炼-230mm×1220 mm板坯连铸。53 t中间包钢水过热度为25~30℃,钢包到中间包采用长水口全程吹氩保护浇铸,中间包至结晶器采用浸入式水口浇铸。结果表明,在RH、中间包、结晶器过程中钢中总氧以及夹杂物数量和尺寸均明显降低;但在钢包到中间包过程T[O]、[N]和钢中夹杂物数量增加,说明长水口浇铸过程存在二次氧化。连铸坯中T[O]、[N]平均他分别为11×10-6和30×10-6,显微夹杂物数量平均为4个/mm2。铸坯中的显微夹杂物主要为3~5μm的AlN,同时存在少量的MnS、Al2O3·AlN和Al2O3·MgO·MnS。 The steelmaking flow sheet for two heats non-oriented silicon steel XG800WR(/%:0.003~0.004C. 0.71~0.75Si,0.32~0.33Mn,0.004~0.007S,0.016P) is hot metal pretreatment(KR)-210 t top and bottom combined blown converter-ladle argon blowing-RH decarburization refining-230 mm×1 220 mm slab casting.The superheating extent of liquid in 53 t tundish is 25~30℃,whole casting is shielded by blowing argon with long nozzle from ladle to tundish and the submerged nozzle is adopted in casting from tundish to mold...
无取向硅钢成品钢卷头、尾磁性能差异探讨
结合工业化生产过程中出现的同卷带钢头、尾磁性能差异现象,对50SW1300牌号无取向硅钢同卷带钢头、尾试样的夹杂物、晶体织构和显微组织进行了分析研究。结果表明,夹杂物、晶体织构是影响成品钢卷磁性能的重要因素。夹杂物是造成同卷带钢头、尾铁损差异的主要原因。夹杂物数量越多,尤其是小尺寸的夹杂物数量越多,对成品带钢的磁性能影响越大,对于本试验而言,AlN和MnS是影响成品带钢磁性能的主要夹杂物。晶体织构是造成同卷带钢头、尾磁感应强度差异的主要原因。有益的{100}和Goss织构含量越大,有害的{111}<110>和{111}<112>织构含量越小,即有益织构与有害织构含量比越大,成品带钢的磁感应强度越大。 Based on the industrial manufacture of non-oriented silicon steel sheets 50SW1300, the magnetic property variation of head and tail of the same finished steel sheets was discussed by analyzing non-metallic inclusion, crystal texture, and microstructure. Results show that, both of the non-metallic inclusion and the crystal texture will affect the magnetic properties significantly. The non-metallic inclusion is the key factor of the core loss variation of head and tail of the same finished steel s...
无取向硅钢热轧边裂的形成原因
利用加热炉模拟、动态再结晶以及热模拟等试验方法以及扫描电镜、金相显微镜等分析观察手段对无取向硅钢边裂的成因进行了探讨。结果表明,长时间加热使得板坯边部晶粒异常长大,晶界氧化并脱碳,轧制过程中边部温度过低,动态再结晶过程变弱,使得板坯边部延伸性能变差,是导致硅钢边裂的主要原因。建议通过适当降低铸坯加热温度、缩短保温时间、提高终轧温度来改善硅钢边裂缺陷。 The behaviors of high temperature oxidation,dynamic recrystallization,and hot ductility,microstructure evolution were investigated on the non-oriented electrical steel sheets to discuss the formation of edge crack.The key causes of cracking was found to be the coarse as-cast microstructure,grain boundary oxidation and decarburization in reheating furnace,as well as reduced temperature at strip edge region during hot rolling process resulting in reduced hot ductility and lack of enough dynamic re...
低牌号无取向电工钢磁时效行为分析
选取了三种50W 800无取向电工钢,分析了化学成分、晶粒尺寸、织构、以及200℃时效处理48 h前后的磁性能和第二相粒子析出状态的变化。结果表明,钢板中第二相粒子的分布密度对钢板铁损有最重要的影响。降低钢中C、N元素含量,或改进钢板热加工参数以降低成品钢板中第二相粒子形成元素的过饱和度均有利于明显降低钢板磁时效过程中的铁损增幅。钢板中对磁性能有利的织构也有利于降低钢板铁损的时效幅度。 The evolution of chemical composition,grain size,texture,as well as magnetic property after aging treatment at 200 ℃ for 48 h and distribution of second phase particles precipitation in three selected 50W800 non-oriented electrical steels were analyzed.The results show that the distribution density of second phase particles has great influence on core loss.Reducing C and N content,or improving hot-working parameters to reduce the supersaturation of elements forming second phase particles in prod...

