钢厂
高强度无取向电工钢疲劳性能及断裂机制
测试了高强无取向电工钢的S-N曲线,并借助光学显微镜、扫描电子显微镜、透射电子显微镜分析了实验钢组织,疲劳断口形貌和位错结构。结果表明:室温条件下,频率为20Hz,应力比R为0.1,循环10~7周次时,实验钢的疲劳强度为360MPa,疲劳裂纹萌生于实验钢的次表面,裂纹萌生点附近有沿晶开裂现象,疲劳裂纹扩展区域有解理台阶与疲劳条纹,瞬间断裂区是韧性断裂,有大量韧窝。实验钢在循环应力作用下基体中产生了大量位错,并有驻留滑移带终止在晶界位置。 The S-N curve of a high strength non-oriented electrical steel was tested.The microstructure and fatigue fracture morphology and dislocation were analyzed by optical microscope,scanning electron microscope,transmission electron microscope.The results showed that:at room temperature and the frequency of 20 Hz and the stress ratio Rof 0.1,the fatigue strength of the experimental steel was 360 MPa when the cycle was 10~7 cycles.The fatigue crack initiation at the surface of the steel and the interg...
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...
电脉冲对取向硅钢凝固组织的影响研究
对取向硅钢熔融态钢液进行处理,对比研究了不同脉冲参数的作用效果。结果表明,电脉冲对钢锭晶粒组织具有明显的细化作用,凝固组织等轴晶比例大幅上升。在脉冲电容、频率、处理时间和电压中,影响等轴晶比例的最显著性因素为脉冲频率;最优正交实验参数为:电容1 200μF,脉冲频率1 Hz,处理时间5 s,脉冲电压800 V;随着输入能量的增大,等轴晶率先增大后减小,脉冲输入能量为某值时,等轴晶率最大,通过经典形核理论和热力学对这一现象进行了解释。 Research on the influence of the electric pulse on the solidification structure of oriented silicon steel was preformed.Electric pulses in different parameters were applied to molten steel and results were compared.The result shows that solidification structure of oriented silicon steel can be improved by the electric pulse,and the equiaxed crystal ratio increases obviously.Among the four parameter factors of electric capacity,frequency,applied time and voltage,the most effective factor is frequ...
电动汽车电机用电工钢疲劳性能测试技术研究
电动汽车电机在高速旋转时承受离心力和电磁力的作用,在进行电机转子设计时,既要考虑电磁性能,还要考虑机械性能。对电机转子受力情况进行了综述,分析了转子用电工钢疲劳性能参数的重要性,详细阐述了试样抛光、表面处理、试样的对中和安装对测试结果的影响。 The motor of electric vehicle bears big force for high speed rotors,mainly including centrifugal and electromagnetic forces.The magnetic and mechanical aspects of the electrical steel are crucial to machine design.In this paper,the forces applied on the motor were summarized and importance of fatigue properties was analyzed.The influence of specimen polish,surface treatment,alignment and installation on fatigue testing result were represented in detail.
铜含量对TSCR工艺生产取向硅钢热轧织构的影响
取向硅钢热轧板中织构梯度对发展完善的二次再结晶十分关键,通过添加铜可以显著降低取向硅钢板坯加热温度,从而影响热轧板织构分布。利用X射线衍射仪,分析了实验室模拟薄板坯连铸连轧(TSCR)工艺的3种不同铜含量的取向硅钢热轧板织构。结果表明:不同铜含量热轧板表面到厚度1/4处均为弱的热轧织构,热轧板心部主要为{100}面织构;铜含量约在0.4%时,热轧板次表层的{110}<001>织构比例最高,而热轧板心部的{100}<110>织构比例最低;铜含量对热轧织构中{114}<110>和{001}<100>织构发展有显著影响。 The texture gradient in hot rolled grain oriented silicon steel strip is one of the essential factors to achieve a perfect secondary recrystallization.The addition of copper can significantly reduce the slab reheating temperature of grain oriented silicon steel,so as to impact the texture distribution in the hot rolled strip.The texture of hot rolled grain oriented silicon steel strip as-rolled by thin slab casting and rolling process(TSCR) in laboratory with three different copper contents was ...
制备硅钢级氧化镁前驱体的原料水化研究
以青海盐湖水氯镁石为初级原料,采用喷雾热解法制备原料氧化镁,原料氧化镁通过水化制备硅钢级氧化镁前驱体氢氧化镁。原料氧化镁水化实验中对水化剂、水化温度、水化时间、液固比、搅拌速度及陈化时间对水化率、过滤速度和纯度的影响进行系统研究。采用均匀实验设计和DPS数据处理,(依次)通过建模分析、二次多项式模型回归建立数学模型,再通过各因素方差分析和总方差分析,确定了理论最优实验条件,再用理论最优条件作重复实验进行验证,最终确定了原料氧化镁的最佳水化条件。在水化温度60℃,水化时间105 min,液固比4,陈化时间4 h,水化剂1含量4.0%,水化剂2含量3.15%,洗水量4倍,搅拌速度120 r/min时,原料氧化镁的水化率达99.50%以上,得到的硅钢级氧化镁前驱体氢氧化镁纯度高、过滤性能良好。 By spray pyrolysis method,bischofite in Qinghai salt Lake,as primary raw material,was used to prepare precursor raw material MgO for silicon-steel MgO.The precursor raw material MgO was used for preparing Mg(OH)2 which was the precursor of silicon-steel MgO,by hydration method.In the hydration experiment of precursor raw material MgO,some experiment parameters were investigated systematically.such as the hydrated agent,the temperature and time of hydration,liquid/solid ratio that affected the hy...
火花源原子发射光谱法在线测定电工钢中的超低碳
采用火花源原子发射光谱分析测定电工钢中超低C,研究试样制备方法、Ar纯度和压力等条件对分析结果的影响,并对工作曲线进行了优化,实现了一次分析同时测定电工钢的多种元素,满足炉前和精炼在线分析的要求。 Ultra-low carbon in electrical steel is determined with spark-source atom emission spectrum.It is researched the influence of sample making method,purity of Ar,and pressure on analysis result.The work curve is optimized.The determination of many elements in electrical steel only in one analysis is realized.It meets demands of on-line analysis for blast furnace and refining.
电工钢铸锭内析出相粒子特征及回溶行为
利用场发射电镜及能谱仪研究了取向电工钢薄、厚板坯铸锭中不同区域的析出相差异,确定了MnS、AlN及Fe3C的析出顺序和形貌特征。结果表明AlN以先析出的MnS为形核核心,形成粗大微米级的复合析出相。针状Fe3C既可以在复合析出相表面形成也可以在基体中单独出现,主要受冷却速度的影响。在1250℃保温1～2 h,AlN、Fe3C均可完全回溶,但部分MnS仍不回溶。MnS尺寸随着保温时间延长而增大。导致热轧板中沿轧向分布的粗大MnS,减弱了粒子钉扎力。 Precipitates in thin and thick slabs of electrical silicon steel were investigated by means of field emission SEM and EDS analysis.The precipitation sequence and the morphology of MnS,AlN and Fe3C particles were identified.AlN particles are observed to be nucleated on surface of MnS forming micron-meter-sized complex particles.Acicular Fe3C can precipitate on surface of the complex MnS/AlN particles or directly from matrix depending on cooling rate of the slabs.After holding at 1250 ℃ for 1-2 h,...
