常化处理对50W800电工钢组织、织构与磁性的影响

以企业不常化的50 W800热轧板为初始材料,利用金相显微技术、EBSD技术,对比研究了不同常化温度对50 W800成品板组织、织构及磁性能的影响。结果表明,常化后板材表层晶粒显著粗化,晶粒尺寸可达500μm以上,这层粗大的晶粒有利于成品板的磁性能,常化可提高0.041 T的B50磁感,降低0.6 W/kg的P1.5/50铁损。与不常化的成品板对比,经过常化后的成品板{111}织构比例降低,Goss织构比例略有增加,磁感增加。成品板晶粒尺寸与初始的常化板晶粒尺寸没有直接对应关系,常化板晶粒尺寸越大,形变剪切带形核越多,成品板再结晶晶粒尺寸越小;晶粒长大阶段非{111}取向晶粒长大能力明显高于{111}取向晶粒,延长保温时间可有效发挥常化的改善磁性的作用。     

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...     

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。     

薄板坯连铸连轧流程Fe-3%Si钢热轧板和常化板织构

在实验室按照薄板坯连铸连轧工艺流程试制了Fe-3%Si硅钢热轧板,采用EBSD和X射线衍射方法观察了A钢和B钢热轧板和常化板的织构组织,分析了α、ε和γ取向线上织构取向密度变化规律。A和B钢热轧板具有相似的{110}〈112〉和、{001}〈110〉和{001}〈010〉和高斯织构组织,A试样表层的晶粒均匀性较差,B试样具有较强的γ织构取向。采用EBSD观察比较了A钢和B钢热轧板和常化板的垂直TD面的EBSD微观织构组织,A钢和B钢常化退火后基本保留了热轧时形成的中心部位的组织,而次表层和表层晶粒发生了再结晶长大,晶粒组织和织构梯度减小,织构主要集中在{001}〈^-1^-10〉和{001}〈0^10〉和之间以及高斯织构上。常化后织构的总体强度下降,高斯强度减弱。试验研究结果为开发薄板坯连铸连轧短流程生产电工钢技术提供理论依据和参考数据。     

退火温度和时间对冷轧无取向硅钢组织与织构的影响

针对冷轧无取向硅钢退火工艺的特点,研究了退火温度和保温时间对成分为0.004%C、0.33%Si的冷轧无取向硅钢晶粒组织和织构演变的影响.结果表明:退火后,α线上{100}织构密度明显减弱,取向从{112}〈110〉向{111}〈112〉大量聚集;适当增加保温时间有助于提高{100}〈hkl〉织构,900℃、保温180 s,水冷得到的织构分布比较均匀,{001}面织构占有率比较高.     

低温板坯加热晶粒取向3.0%Si钢高温退火中的组织演化

采用取向分布函数及金相分析方法研究了以Cu₂S为主要抑制剂的低温板坯加热晶粒取向硅钢(%:0.04C、3.16Si、0.50Cu)在650～1 050℃高温退火中组织的演化过程。结果表明,该取向硅钢的初次再结晶温度为650～700℃,二次再结晶温度为1 000～1 050℃。初次再结晶后的主要织构强度以{111}〈110〉、 {112}〈110〉、 {111}〈112〉顺序减弱。初次再结晶组织的晶粒尺寸和织构强度在700～900℃变化很小,在900～1 000℃晶粒长大速度加快,{111}〈110〉、{112}〈110〉组分增强,而{111}〈112〉组分的强度基本保持不变。     

冷轧压下率对薄规格取向硅钢冷轧和退火织构的影响

实验采用不同厚度的低温取向硅钢热轧板冷轧至0.18 mm。通过XRD分析冷轧板表面和中心层的织构,通过EBSD分析了脱碳板截面的织构。结果表明,冷轧样品表层和中心层,随着压下率增大,{111}面织构总含量有所减少,{100}面织构总含量有所增多;脱碳样品中{111}面织构明显增多,尤其是{111}〈112〉织构组分,{100}面织构明显减少,尤其是{100}〈011〉织构组分,{411}〈148〉织构组分也明显增多;脱碳样品中,随着压下率增大,晶粒尺寸逐渐减小。不利于二次再结晶发展的织构随着压下率的增大明显增加,同时有利的CSL晶界随着压下率的增加会稍有减少。     

热轧常化温度对3．0%Si无取向电工钢组织和性能的影响

当常化温度由850℃提高至1 100℃,0.005%E-3.0%Si无取向电工钢2.5 mm热轧板的平均晶粒尺寸由60μm增至200μm;当热轧板常化温度为1 000℃,0.5 mm冷轧板850℃+950℃退火后的晶粒尺寸最大,为105μm。随热轧板常化温度提高,冷轧板退火后{111}、{112}和{114}织构明显减弱,{100}织构增强,热轧板最佳常化温度为900～1 050℃,该电工钢的铁损最低。     

无取向硅钢热轧板常化过程中的织构演变

 通过对取向分布函数（ODF）的分析,研究了无取向硅钢热轧板在常化过程中不同厚度位置的织构演变情况。结果表明,热轧板内部在常化过程中发生再结晶,不同位置的织构变化不同,表层处织构变化不明显,各组分混乱分布且强度不高;1/4板厚处热轧板和常化板的高斯织构都比较强,但900 ℃常化后高斯织构强度有所降低;中心层常化前后织构发生明显变化,{111}<112>织构强度增强。     

常化处理对1.1 %Si无取向硅钢组织和性能的影响

针对Si的质量分数为 1.1 % 无取向硅钢试验材料,通过980 ℃×140 s常化和未常化处理,采用XRD、EBSD和磁性能测量技术对比分析了常化和未常化对 1.1 %Si 无取向硅钢常化、退火态组织、织构与成品磁性能的影响。结果表明：980 ℃×140 s常化处理使热轧组织增大约23 μm,最终成品晶粒尺寸增大约12 μm,均匀性提高;常化后的组织的{100}织构增强约 3.0 % ,{111}取向织构减弱约 2.6 % ,成品{100}织构增强约 0.43 % ,{111}取向织构减弱约 6.5 % ;硅钢磁感 B50 值提高 0.021 T ,铁损 P1.5/50 值降低 0.34  W/kg。     

CSP制无取向硅钢热轧、常化、冷轧织构的演变

运用EBSD和X射线衍射技术,研究了模拟CSP流程生产无取向硅钢在热轧-常化-冷轧过程中织构的演变。热轧板沿板厚方向应力场和温度场的差异导致由表至中织构锋锐度增高,织构类型存在明显变化,表层主织构为B类纤维织构,次表层为A类纤维织构,中心层为旋转立方织构{001}<110>。常化过程削弱了这种差异性,但中心层仍保留了一定强度的立方织构{001}<100>。冷轧板表层及中心层的主织构均为{112}<110>、{111}<112>,表层织构锋锐度较中心层的强。分析表明热轧、常化、冷轧织构的演变与基体初始织构、组织密切相关。表层、次表层热轧板织构经常化演化成散漫、分布较均匀的织构,中心层主要织构由{001}<-1-10>绕RD逆时针旋转45°演化至{001}<0-10>。冷轧后织构演变为以{223}<110>为主的B类织构和以{111}<112>为主的A类织构。     

Comparison between simulated and experimental transformation textures in a Nb microalloyed steel

Samples of a Nb microalloyed steel were control rolled and finished (i) at 1020°C (in the γ recrystallization range) and (ii) at 870°C (in the γ no-recrystallization range). The textures of these materials were compared with b.c.c. transformation textures derived analytically from (i) annealed and (ii) cold rolled samples of an f.c.c. Ni30Co alloy. For this purpose, the Kurdjumov-Sachs relationship was assumed, together with the absence of variant selection. The ferrite texture of the experimental steel finish rolled in the γ recrystallization range is sharper than the corresponding simulated texture, the major components of both being {100}〈011〉 and {110}〈110〉. The texture of the experimental steel finish rolled in the γ no-recrystallization range is again sharper than the corresponding simulated texture, both containing {113}〈110〉, {332}〈113〉 and {100}〈011〉 as the major components. The detailed textural features of the steel finished at 1020°C can be explained by allowing for some variant selection, together with selective growth of the {100}〈011〉 oriented α grains during transformation. A combination of selective α grain growth and variant selection is again required to explain the detailed texture of the steel sample finished at 870°C.     

常化及冷轧压下率对Hi-B钢初次再结晶织构影响

 为了研究Hi-B钢的常化工艺(二段式常化)及不同冷轧压下率(63.8%、75.2%及87.1%)对其初次再结晶退火（820 ℃,5 min）后织构的影响,采用CSP工艺试制以Cu2S和AlN作为抑制剂的方法进行模拟。利用NOVA400 Nano SEM场发射扫描电子显微镜对初次再结晶退火后的微观织构进行EBSD数据采集,从晶粒取向、ODF分析以及特征取向线分析3个方面对织构进行分析。结果表明,经常化后再冷轧初次退火后Hi-B钢的组织更加均匀,高斯织构和有利的{111}〈112〉织构相对较多,织构间发生了转变,对产生高斯织构有利的{111}〈112〉织构为主要转变产物。在压下率为87.1%时,有良好的晶粒取向以及合适的取向线分布。     

Textures of low carbon and titanium bearing extra low carbon steel sheets hot rolled below their AR3 temperatures

The textures of warm rolled low carbon and Ti-bearing extra low carbon steel sheets have been investigated using ODF's ECC-ECP (electron channeling contrast-electron channeling pattern) and selected area electron diffraction and the following results were obtained: (1) The main orientation of the low carbon steel sheet was near {113}〈110〉 while that of Ti-bearing extra low carbon steel was near 〈111〉//ND. (2) The recrystallization of the low carbon steel occurred mainly from deformed {100} grains while the main nucleation sites in the Ti-bearing extra low carbon steel were the grain boundaries of the deformed {111} grains. (3) The main orientations of grains recrystallized from deformed {100} grains are {100}〈110〉−{112}〈110〉 for both steels. (4) The orientation of the grains recrystallized from the deformed {111} grains of the Ti-bearing extra low carbon steel is mostly near 〈111〉//ND and that of the low carbon steel is mainly near {114}〈110〉. This difference is discussed in terms of the influence of carbon in solution on the crystal rotation at nucleation sites. (5) It is concluded that the different recrystallization textures formed in the two steels is explained by the difference in the preferred nucleation sites and in the local crystal rotations in the vicinity of grain boundaries.     

0.20 mm薄规格取向硅钢的开发及关键工艺探讨

为开发磁性能优良的0.20 mm薄规格取向硅钢,对该取向硅钢的组织特征,不同冷轧压下率和高温退火气氛对磁性能的影响进行了研究。结果表明：所获得的0.20 mm薄规格取向硅钢成品组织二次再结晶完全,铁损（P1.7/50）为0.89 W/kg,磁感（J800）为1.906 T;热轧和常化1/8层的主要织构组分为Goss织构,冷轧织构为较强的{001}〈110〉,退火织构主要为{411}〈148〉,脱碳晶粒尺寸约为21.17 μm,Goss晶粒极少;0.20 mm薄规格取向硅钢合适的冷轧压下率为91.3 %;高温退火升温段合适的气氛为75% N2。     

初次再结晶退火对模拟CSP含Cu Hi-B硅钢组织和织构的影响

在实验室用模拟CSP工艺试制Hi-B高磁感取向硅钢薄板（/%:0.07C,3.02Si,0.13Mn,0.020P,0.006S,0.21Cu,0.025Cr,0.016A1,0.004Sn）,该钢经25kg真空感应炉熔炼,铸成41 mm×120 mm板坯-热轧成2mm板-1 120℃常化-冷轧成0.27mm薄板。研究了830~870℃,3~7min退火对再结晶组织和织构的影响。结果表明,0.27mm含Cu Hi-B高磁感取向硅钢板的合适退火工艺为830℃ 5 min,其平均晶粒尺寸为15.6μm,不利织构{111}〈110〉和{001}〈110〉含量较低,有利织构{111}〈112〉分布合理,有利于在二次再结晶退火过程形成良好的高斯组织。     

JSP-双机可逆冷轧条件下IF钢织构研究

针对济钢现场工艺条件下生产的Ti-IF钢,利用X’Pert ProxX射线衍射宏观织构分析方法,研究了中薄板坯热连轧轧制及随后的冷轧、退火工艺过程中织构的变化规律。IF钢冷硬板主要织构类型为{111}〈110〉、{111}〈112〉和{001}〈110〉,其中{111}〈110〉织构强度达到12;再结晶退火后的IF钢退火板,主要织构类型为{111}〈110〉和{111}〈112〉,{111}〈110〉织构强度提高到15.37。济钢生产的Ti-IF钢获得了对板材成形最有利的{111}//ND织构。     

Texture evolution by grain growth in the presence of MnS and AIN precipitates in Fe-3% Si alloy

Texture evolution by grain growth in the presence of MnS and AIN precipitates in Fe-3% Si alloy was investigated by X-ray diffraction and electron channelling technique. Two texture groups A and B evolved from the primary texture (grain diameter of 6 μm) composed mainly of {111} 〈112〉 oriented grains. The group A (grain diameter of 2600 μm) were mainly composed of two subgroups, one with Goss oriented grains and another with Goss oriented grains rotated around ND axis by about 15 and 20°, while the group B (grain diameter of 700 μm) had an intensity level of about one seventh of that of the group A and had orientations centering around {112} 〈110〉. The ideal Goss or near Goss oriented grains of group A were infrequent in the primary recrystallized structure and made few Σ1 boundaries. They made large numbers of Σ9 boundaries though, or had a large value of the product (number of grains at orientation × number of σ9 boundaries made by them). The grains in orientations within the texture group B were fairly frequent in the primary structure and made large numbers of Σ1 boundaries. The value of the product (number of grains at orientation × number of Σ9 boundaries made by them) was large. The mechanism of the evolution of the A and B groups is considered to be due to (1), the higher mobility, in the presence of precipitate inhibitors, of adjacent grains in Σ9 coincidence or in coincidence orientations with a 〈110〉 rotation axis; (2), because Σ1 related grains are stable and less mobile under these conditions.     

IF钢罩式退火过程中再结晶组织与织构的演变

研究了IF钢(/%:0.005C、0.02Si、0.16Mn、0.011P、0.004S、0.042Als、0.061Ti、0.003 1 N)0.8 mm冷轧板在500～800℃退火时的再结晶组织及织构,采用X射线衍射技术结合微观组织观察分析了IF钢罩式退火过程中{111}再结晶织构形成机制和显微组织演变规律。结果表明,随退火温度的升高,再结晶数量逐渐增多,640℃为实验钢实际再结晶温度,同时{111}再结晶织构强度亦逐渐增大,{111}取向的晶粒主要在再结晶过程中形成,并在{111}取向晶粒长大过程中,γ纤维织构之间也发生相互转化,主要由{111}〈112〉织构转变为{111}〈110〉织构。