低温取向硅钢初次再结晶动力学模型及织构演变

研究了低温取向硅钢在625~850℃的等温退火过程,根据Avrami方程建立了其初次再结晶动力学模型,并利用EBSD技术对初次再结晶织构演变过程进行了分析。结果表明:当退火温度为850℃时保温5s即可发生完全再结晶;而在625℃下保温1.7h以上再结晶才能进行完全。当退火温度在625~700℃时,Avrami指数n在0.82~0.89之间,当退火温度在750~850℃时,n值在1.25~1.27之间,相对应的再结晶激活能QRX分别为239.3、160.4kJ/mol。初次再结晶早期主要发生在高储存能的γ纤维织构上,而中后期则主要发生在低储存能的α纤维织构上。初次再结晶完成后织构类型主要是以{111}112组分为主的γ织构、{114}418织构及少量分布在次表层的Goss织构。     

取向硅钢板坯加热温度对热轧及冷轧板织构的影响

 采用取向分布函数及取向线分析方法对取向硅钢高温和低温板坯加热工艺的热轧及冷轧钢板织构进行了研究。结果表明：低温与高温板坯加热工艺的热轧板及冷轧板织构组分有明显不同。低温板坯加热热轧板中{100}<001>及{110}<110>织构较强,但经冷轧后{001}<110>织构最强。     

低温加热取向硅钢组织与织构演变研究

采用OM、EBSD、XRD分析研究了含Cu低温加热取向硅钢组织、织构的演变特征,研究结果表明：热轧板中存在铁素体层和珠光体层彼此交替的带状组织,且显微组织在厚度方向上分布不均匀,热轧板中{001}〈110〉、{112}〈110〉织构以及{110}〈001〉织构在板厚方向上分布不均匀;经过冷轧后,铁素体晶粒被严重拉长,形成了沿轧向伸长的纤维状组织,冷轧板织构类型主要是α织构和γ织构;脱碳时基体发生回复再结晶,显微组织为单一的铁素体等轴晶粒,织构主要为γ织构;二次冷轧板经渗氮后织构仅从强度上有所降低,其织构类型变化不明显。成品二次再结晶组织发展比较完善,晶粒尺寸约为10~20 mm。织构类型为锋锐的Goss织构。成品磁感B800达到了1.926 T,铁损P1.7/50为1.047 W/kg。     

日本取向硅钢板坯低温加热的研制现状

简述了取向硅钢板坯低温加热的必要性，并介绍了国外取向硅钢板坯低温加热工艺的研制现状。     

低温板坯加热取向3%硅钢热轧板的研究

研究的两种取向硅钢(%:No1-0.042C、3.16Si、0.009Al、0.07Mn、0.50Cu、0.015S、0.0084N和No2-0.040C、3.20Si、0.014Al、0.22Mn、0.49Cu、0.016S、0.008 2N)由50 kg真空感应炉冶炼,锻成(mm)350×120×35板坯,经1 250℃30 min加热,开轧温度1 100℃,5道次热轧成2.3 mm板,终轧温度950～1 000℃。实验结果表明,两热轧板沿板厚方向存在组织和织构的不均匀性,热轧板次表层为再结晶组织,有较强的Goss织构组分;中心层为形变组织,具有典型的形变织构。含0.22%Mn的No2钢次表层{110}〈001〉织构组分比含0.07%Mn的No1钢弱,中心层{001}〈110〉织构组分大大强于0.07%Mn No1钢,导致两者磁性能差异,0.22%Mn No2钢磁感应强度(B₈₀₀)和铁损(P_1.7/50)分别为1.87 T和1.24 W/kg,0.07%Mn No1钢分别为1.88 T和1.18 W/kg。     

铌对低温取向硅钢初次再结晶行为的影响

以含铌取向硅钢铸坯低温加热制备高磁感取向硅钢为研究目标,通过研究铌对低温取向硅钢初次再结晶行为的影响,达到获得有利于二次再结晶发展的初次再结晶组织目的,采用OM和EBSD技术主要对比了 0.055％铌和不含铌对低温取向硅钢中间退火板的初次再结晶组织、织构和晶界特征的影响.结果表明,铌的加入,使硅钢基体中形成了细小弥散的...     

取向硅钢薄带形变再结晶组织及织构演变

利用背散射电子衍射微织构分析技术及X射线衍射织构分析技术,结合对取向硅钢薄带再结晶各阶段退火板磁性能的分析,系统研究了其形变再结晶过程中的组织及织构演变.结果表明,薄带内原始高斯晶粒取向发生绕TD轴向{111}〈112〉的转变,同时晶粒取向还表现出绕RD轴的附加转动,这种附加转动及其导致的表层微弱立方形变组织可为再结晶立方织构的形成提供核心.退火各阶段样品磁性能的变化对应了{110}-{100}〈001〉有益织构及其他织构的强弱转变以及再结晶晶粒不均匀程度的变化,综合织构类型及晶粒尺寸的变化推断发生了二次及三次再结晶过程.升温过程再结晶织构演变主要体现了织构诱发机制,也即与基体存在绕〈001〉轴取向关系的晶粒长大优势结合高斯织构的抑制效应发挥作用;而在高温长时间保温后三次再结晶过程,{110}低表面能诱发异常长大发挥主要作用使得最终得到锋锐的高斯织构.     

低温板坯加热Hi-B钢的组织和织构演变

采用光学显微镜和X射线衍射仪对低温板坯加热Hi-B钢的组织、织构的特征演变进行了研究。结果表明：从热轧板和常化板的表面到中心,组织和织构分布不均匀。热轧板组织分为表层再结晶区域、再结晶和变形晶粒混合区域和中心变形晶粒区域,并且热轧板各层的织构类型不同。常化板表层晶粒长大,过渡层和中心层的形变晶粒基本消失,常化板继承了热轧板的织构特点。冷轧板为纤维状变形组织,冷轧后形成了以{001}<110>～{111}<110>为主的α织构。脱碳渗氮板的横断面和纵断面的晶粒平均尺寸分别为25.9μm和25.3μm,织构主要为{111}<112>、{114}<481>和{001}<120>织构。成品板晶粒平均尺寸为19.1μm,成品板为单一的高斯织构。     

不同厚度低温渗氮型取向硅钢初次再结晶组织、织构差异分析

以0.27 mm、0.23 mm和0.20 mm三种厚度且磁性能都较好的取向硅钢样品为研究对象,通过EBSD技术对其对应的初次再结晶晶粒尺寸及织构进行研究,从而探索不同板厚度对应的最佳初次再结晶组织和织构是否存在异同。结果表明：三种厚度对应的最佳一次再结晶晶粒平均尺寸均在20～22μm范围内,沿板厚侧面的平均晶粒尺寸基本接近,约为21.4μm; 0.27 mm的中心层区域的平均晶粒尺寸比表层更大,而随厚度继续减小,表层和中心层平均晶粒尺寸逐渐接近。随板厚度的减小,初次再结晶织构增强,主要织构{114}〈481〉、{111}〈112〉以及{100}〈021〉织构均在一定程度上增强,其中{114}〈481〉织构的强度又显著高于其他织构;{114}〈481〉组分面积百分比增加,Goss以及{210}〈001〉组分减少。在这三种厚度样品中,表层区域的Goss、{210}〈001〉和{114}〈481〉组分比例都高于中心层,{100}〈021〉以及黄铜组分比例都低于中心层。随着厚度的减薄,表层和中心层区域的{114}〈481〉、{111}〈112〉织构以及中心层区域的{100}〈021〉织构都明...     

降低取向硅钢板坯加热温度的研究

传统取向硅钢生产技术的特点是:以MnS作为抑制相的板坯,在1350～1380℃的高温加热后进行热轧,然后以二次冷轧法进行生产。这种生产工艺的缺点是能耗大、成材率低、修炉频繁、限制轧机能力、成本高。实验室研究表明:通过适当调整钢中的C、Mn、S含量,严格控制酸溶铝含量,同时加入微量的晶界富集元素,可以把取向硅钢板坯的加热温度降低到1250～1300℃。在后步工序的配合下,可以生产磁性良好的产品。本研究是根据实验室的研究成果,在武钢大生产的条件下,为验证降低取向硅钢板坯加热温度的可行性而开展的。并从化学成分、热轧、冷轧、退火工艺方面进行了详细的分析,确立了在大生产条件下最佳的化学成分及工艺参数。得出结论:大生产条件下降低取向硅钢板坯的加热温度是可能的。     

取向硅钢低温铸坯加热技术的研发进展

取向硅钢高温铸坯加热工艺是长期困扰各大取向硅钢生产厂的一个技术难题.近20年来,开发低温铸坯加热工艺一直是该领域的研究热点.通过对取向硅钢低温铸坯加热新工艺中不同抑制剂方案的分析比较,并结合世界各大钢铁企业对低温铸坯加热工艺的开发及应用情况,对目前低温铸坯加热技术的发展现状进行了全面的总结.     

低温加热生产取向硅钢中MnS和Cu2S的竞相析出

针对薄板坯连铸连轧流程(TSCR)生产具有低温加热(1200℃)抑制剂成分取向硅钢,研究了薄板坯连铸、均热以及热连轧过程中MnS和Cu2S的析出特征,研究结果表明,连铸过程形成的MnS在1180℃下难以完全固溶,并形成尺寸为200~600 nm的粗大MnS粒子,而在此温度下Cu2S可以完全固溶并在热连轧过程中细小弥散析出,平均粒子尺寸约为30 nm,可以作为取向硅钢的有效抑制剂。     

Correlation between Primary and Secondary Recrystallization Texture Components in Low-temperature Reheated Grain-oriented Silicon Steel

Low-temperature slab-reheated grain-oriented silicon steel is characterized by a sharp{411}148 primary recrystallization texture.To date,the influence of this texture on secondary recrystallization is not clear.Microtextures in primary and secondary recrystallized sheets of low-temperature reheated grain-oriented silicon steel were examined using electron backscatter diffraction.By comparing the textures and microstructures of specific primary recrystallized grains neighboring secondary grains with those of other primary grains,the influences of primary recrystallization textures and microstructures on the orientations of secondary grains were investigated.Results show that for low-temperature reheated grain-oriented silicon steel,the primary recrystallization sheet comprises {411}148,{111}112,and{001}120 texture components.During secondary recrystallization,the{111}112 primary recrystallized grains were easily consumed by abnormally grown Goss,deviated Goss,Brass,or{210}001grains;the{411}148 primary recrystallized grains were more resistant to being swallowed;and the{001}120grains were the most resistant to being consumed.For a particular primary grain,the distribution of its surrounding grain boundaries determined how easily it is consumed during secondary recrystallization.Primary grains surrounded by 20°-45°grain boundaries were consumed much earlier than those having grain boundaries above 45°,which is in accordance with high-energy grain boundary theory.In addition,special Σ9 boundaries between {411}148 and Goss grains move more slowly than Σ9 boundaries between{111}112and Goss grains,which is attributed to the different positions of110 rotation axis with respect to the normals of grain boundaries.     

采用低温板坯加热工艺生产的取向硅钢中抑制剂的研究

 对采用低温板坯加热工艺生产的取向硅钢的抑制剂析出行为进行了研究,试验结果表明,本工艺的抑制剂是在热轧阶段开始弥散析出的,热轧板、脱碳退火板和回复板析出相的抑制能力呈递增趋势。抑制剂以Cu2S为主,还有一定量的（Cu,Mn）S、Cu2S+AlN等复合析出相,AlN不起抑制剂作用。     

薄板坯连铸连轧生产取向电工钢模拟实验

 在实验室条件下模拟薄板坯连铸连轧流程试制了取向电工钢。结果表明,实验室条件下模拟薄板坯连铸连轧流程生产取向电工钢是可行的。试制的电工钢成品磁感较好,铁损偏高。实验中,铸坯中柱状晶发达,有穿晶出现,铸坯心部有少量等轴晶。热轧板和常化板晶粒尺寸沿板厚方向有明显变化,组织沿板厚方向可分为表面脱碳层、过渡层、中心层。中间退火后晶粒细小,脱碳退火后晶粒细小均匀。试验中,常化和产品厚度对产品磁性能的影响不明显。     

济钢中板2号加热炉内钢坯温度场仿真研究

利用计算机仿真技术建立中板加热炉的数学模型，依据实际加热条件模拟出炉内板坯各断面的温度分布，并用黑匣子在线测温的方式验证了模拟结果的正确性，为加热炉在线优化控制提供了依据。     

Texture Evolution of Columnar Grains in Electrical Steel During Hot Rolling

Columnar grains in cast slabs of electrical steel show strong anisotropy in grain orientation and morphology and thus influence the subsequent microstructure and texture after hot rolling significantly. The texture evolution of hot rolled sheets containing initial columnar grains with their <100> directions approximately parallel to the rolling direction (RD), transverse direction (TD) and normal direction (ND) of the hot rolled sheets was investigated by using EBSD technique. The results indicated that, whatever the initial texture of the columnar grains was, typical Goss, brass-type and copper-type shear texture component could develop in shear-deformed surface region. The copper-type texture formed under the maximum shearing force with the fine, sheared or dynamically recrystallized grains, and Goss grains were mainly elongated and deformed grains, while brass grains behaved between them. Additionally, the rotating relationship of the three types of shear textures was different due to the restriction of grain boundaries. In homogenously deformed center region, the RD sample contained more {112} <110> grains, and TD sample was covered by {100} textures such as {100}<011> and {100}<021> with coarse grains, while the ND sample developed many {100}<011> grains which were attributed to more {100} grains in the initial sample. Remarkable texture transition occurred on both sides of grain boundaries when {110} grains were adjacent to α-fiber texture grains. It was found that significant texture gradient and preferred distribution of rotating axis existed in the soft orientation grains on the α-fiber when the grains neighbored hard grains on γ-fiber.     

无取向电工钢CSP-冷轧-退火过程中的织构演变

利用ODF图研究了采用CSP工艺生产的热轧带钢为基料的无取向电工钢在冷轧生产过程中的织构演变.结果表明,无取向电工钢冷轧生产过程中,从CSP热轧带钢到退火成品,织构强度逐渐减弱.从热轧带钢到冷轧带钢织构骨架线保持不变,都是沿〈011〉方向.退火态成品织构分布比较均匀.无取向电工钢在冷轧生产过程中,晶粒取向由α纤维线向γ纤维线转动.当w(Si Al)从1.0%增加至1.5%时,在冷轧及退火过程中它对热轧织构的影响逐渐减弱.     

Texture of Cold Rolled Strip of Fe-3Si Steel Produced by Thin Slab Casting and Rolling

 The hot rolled strip of Fe-3Si steel was experimentally produced by thin slab casting and rolling (TSCR) process in the laboratory. The texture evolution rule was investigated during hot rolling and cold rolling. The texture distribution of cold rolled strips with four kinds of cold rolling reduction schedules was observed through X-ray diffraction method, and the orientation density variation of 1/16 layer, 1/8 layer, 1/4 layer, and 1/2 layer in thickness was analyzed. The cold rolled texture of steel A with four kinds of cold rolling reduction schedules was mainly composed of α and γ fibers. Cold rolling reduction ratio of 70% was more beneficial for obtaining more γ fibers. The γ fiber texture orientation density of {111}<011> and {111}<1 12> was the largest on the 1/8 layer and 1/4 layer and the least on the 1/16 layer and 1/2 layer for steel B. The texture orientation density of {001}-{223}<110> in the α fibers for steel C was increased, but the texture orientation density of {332}-{110}<110> was low.