铁基非晶合金带材生产线喷带闭环控制方法的研究

为提高非晶薄带的生产效率,非晶合金薄带生产和X光测厚仪配置,设计了基于PLC的板型闭环控制系统。结果表明,采用X光测厚仪在线检测薄带厚度,根据厚度反馈控制喷嘴包伺服系统进行位置调节,使喷嘴包和冷却辊之间的间距保持动态稳定。同时,设计板型显示器在线显示非晶薄带板型及厚度,实现人机交互。在薄带开始制备时,采用梯度反馈控制策略逐步调整辊嘴间距,可以有效防止超调或者振荡。该系统满足精度和实时性要求,提高了非晶薄带长度和宽度方向的厚度一致性。     

永磁同步电机在非晶带材卷取上的设计与应用

针对异步电机机械特性比较软,非晶带材精度很难达到系统要求的问题,提出使用永磁同步电机卷取伺服系统实现收卷的精度误差小于2%的方法。介绍非晶生产线带材抓取和卷取的工艺过程和要求,通过对三项异步电机和永磁同步电机的机械特性曲线精度对比,对采用双闭环控制的永磁同步电机卷取伺服系统进行理论分析。实际应用过程中的生产数据验证了理论计算的正确性,证明永磁同步电机伺服系统达到了精确的收卷效果,使得系统精度误差小于2%。     

加入Ni基非晶带的TWIP钢激光焊接头组织及力学性能研究

采用激光焊对Fe-Mn-C-Al系TWIP钢进行不加非晶带和加入Ni基非晶带2种方法焊接,对2种方式下的焊接接头组织和力学性能进行了分析。结果表明:TWIP钢焊接接头结合良好,无裂纹等明显缺陷,添加Ni基非晶的焊缝处晶粒比未加非晶带焊缝处晶粒更加细小; 2种方法焊缝处的硬度均高于母材,添加非晶带的焊缝处硬度高于未添加非晶带的焊缝;在拉伸过程中,母材的抗拉强度为1 007 MPa,未加Ni基非晶的焊接试样抗拉强度为1 015 MPa,在焊缝处断裂,而添加非晶带的焊接试样抗拉强度为1 038 MPa,均高于母材和未加非晶带的焊接试样,拉伸时在母材处断裂。     

Nd60Fe30M10（M=Al，Si，Ga）系非晶永磁的性能与组织结构

采用真空快淬设备以辊速5m／s、10m／s、15m／s、20m／s、30m／s制备了Nd60Fe30M10（M=Al,Si,Ga）系的“非晶带”,研究了制备速度对“非晶带”永磁性能和结构的影响。实验结果表明：Nd60Fe30Si10和Nd60Fe30Ga10同经典合金Nd40Fe30Al10一样,也显示出非晶永磁性能,并且比相同条件下制备的Nd60Fe30Al10“非晶带”的永磁性能更好;三种“非晶带”的矫顽力随辊速的降低而提高。对Nd60Fe30Al10“非晶带”的TEM分析表明,以30m／s辊速制备的“非晶带”,有2～5nm的析出物弥散分布在非晶基体上;而以5m／s辊速制备的“非晶带”,有10nm左右和150-200nm的析出物分布在非晶基体上。析出物的生成,促进了矫顽力的提高。     

退火工艺对FeCuNbSiB非晶薄带的磁感应效应的影响

研究了频率、磁场及退火工艺对Fe73.5Cu1Nb3Si3.5B9非晶薄带的磁感应效应及磁感应效应变化幅度的影响。结果表明：非晶薄带的磁感应效应随着频率的升高而增强,随磁场的增强而减弱;非晶薄带的磁感应效应变化幅度随磁场的增强而增大,随频率的升高而减小;与淬火态非晶薄带相比,退火可以提高非晶薄带的磁感应效应变化幅度。且经300℃×1h退火后非晶薄带的磁感应效应变化幅度最大,当测试频率为0．8MHz时,磁场为1412A／m时。淬火态非晶薄带的磁感应效应变化幅度为1．50V,经300℃×1h退火后非晶薄带的磁感应效应变化幅度为1．77V。     

精密合金生产工艺发展的主要方向

精密合金生产工艺发展的主要方向近年来在精密合金生产中日益广泛地运用了熔体快淬非晶带和非晶丝的制取技术，所生产的非晶带和非晶软磁材料具有极其优异的物理性能（磁性，强度和耐蚀性）。但非晶合金的工业生产目前还只是集中在美、日、德、俄等少数几个国家，这主要是...     

矩形脉冲电流退火与激励电流对Co基非晶带巨磁阻抗效应的影响

利用矩形脉冲电流对Co_(66.3)Fe_(3.7)Si_(12)B_(18)非晶带进行退火处理,研究了退火电流密度对非晶带巨磁阻抗效应的影响,同时研究了激励电流频率对退火处理后的非晶带巨磁阻抗效应的影响。结果表明,该非晶带的特征频率为1.4 MHz。最大巨磁阻抗所对应的磁场随激励电流频率的增加逐渐向高磁场方向移动。     

Al86Fe10Zr4非晶合金的晶化与腐蚀行为研究

利用甩带法制备出Al86Fe10Zr4非晶薄带,用X射线衍射仪和差示扫描量热计对该非晶的非晶特性及晶化过程进行了研究.结果表明,Al86Fe10Zr4非晶薄带的晶化过程为两步晶化,其晶化温度分别约为603和718 K.用Kissinger 法得到了合金两步晶化过程的激活能分别为273和239 kJ/mol.对该非晶薄带...     

辊速及晶化工艺对(Nd, Pr)13Fe80Nb1B6快淬薄带组织和矫顽力的影响

用熔体快淬法制备(Nd,Pr)_(13)Fe_(80)Nb_1B_6快淬薄带并晶化处理,研究辊速和晶化条件对其组织和矫顽力的影响.结果表明,在10～20、25和35 m/s分别得到纳米晶、部分非晶和完全非晶薄带,且在18 m/s制备的薄带有较好的c轴各向异性.快淬态薄带的矫顽力随辊速(10～25 m/s)的增大而增加.非晶薄带晶化后由(Nd,Pr)_2Fe_(14)B相和富稀土相组成,且完全非晶薄带晶化后比部分非晶薄带晶化后的矫顽力要高,这是由于前者比后者具有更均匀的微结构造成的.非晶薄带晶化后矫顽力最大为1616 kA/m,高的矫顽力与添加Pr和Nb有关.     

钴基非晶合金薄带应力阻抗效应的研究

通以高频交变电流的钴基非晶带在弯曲时，由于受到应力作用而具有显著的应力阻抗效应，实验中所用的材料是经过适当脉冲电流退火的钴基非晶合金薄带Co66.3Fe3.7Si12B18。研究了阻抗变化率随非晶带弯曲程度的变化关系以及交流电流幅值和频率对非晶带应力阻抗效应的影响。实验结果表明，在弹性体末端位移为正方向时，非晶带具有负的阻抗变化率，而位移方向为负时，具有正的阻抗变化率，且都随位移的增加而增大。在位移一定的情况下，阻抗变化率随着频率的增加先增大后减小，随电流大小的变化关系也具有这种趋势。     

伦茨EVS9300-EP在停剪定尺控制中的应用

介绍了伦茨EVS9300-EP交流伺服位置系统在带材定尺剪切控制中的应用。     

带厚对FeSiB非晶铁芯软磁性能的影响

研究了带材厚度对非晶环形铁芯软磁性能的影响,铁芯由标称成分为Fe91.7Si5.3B3.0(质量分数),分别为带厚22μm,25μm和26μm的带材制成。铁芯在氮气保护下经过653~723K保温1h进行热处理。在5~30kHz以及200~1 000mT(Bm)范围内测试铁芯软磁性能。研究表明,带材厚度影响铁芯软磁性能,随着带材厚度的减小,铁芯动态损耗值、矫顽力和剩磁都逐渐减小,带厚22μm带材绕制的铁芯可以获得最优的软磁性能。     

Tuning the Planar-Flow Melt-Spinning Process Subject to Operability Conditions

An amorphous structure improves the physical properties of metal and enhances material performance. Planar-flow melt-spinning (PFMS) is a rapid solidification process for producing microcrystalline and amorphous metal ribbons. In PFMS, molten metal is fed through a nozzle onto a rotating wheel where the melt freezes and a continuous ribbon is spun. This study proposes a rapid method for process tuning. Examples were used to determine the applied pressure and wheel speed for designing the ribbon thickness and a wheel-nozzle gap with a preset nozzle size. The determined operating variables are suited to operation conditions, enabling the successful production of continuous ribbon. The proposed method was tested using computational fluid dynamics by treating the liquid metal and ambient air as a two-phase flow using the volume of fluid method. This study used the model to predict the puddle shape and ribbon thickness by fixing the dimensions of the wheel-nozzle gap and nozzle slot and varying the pressure and wheel speed. The results from the simulation confirmed the viability of the method and showed a concerted trend for the ribbon thickness compared with previous studies. In addition, the simulation revealed a fluctuation in the ribbon thickness, which was attributed to the first vibration mode of the puddle that was related to the natural frequency of the liquid inertia balanced by surface tension.     

The pressure loss and ribbon thickness prediction in gap controlled planar-flow casting process

The dynamics of the single roller planar-flow casting (PFC) process is modeled using mass balances and the Bernoulli equation to formulate the final analytical solution. The emphasis is focused on the gap controlled PFC process and the prediction of ribbon thickness with given PFC process parameters. The experimental results show that the pressure loss is significant when the flow turns its direction from the nozzle slot into the upstream region of puddle. By introducing the pressure loss into a PFC process model, the predicted ribbon thickness is qualitatively in good agreement with the experimentally measured ribbon thickness in large scale production of amorphous ribbons.     

Cooling wheel features and amorphous ribbon formation during planar flow melt spinning process

A numerical model incorporating actual production conditions of planar flow melt spinning process is presented. Knowledge of the process conditions at which an amorphous ribbon with uniform thickness can be obtained is important to reduce the manufacturing costs. Cooling wheel conditions play a significant role during rapid solidification of the melt. Hence a heat transfer analysis is performed to investigate the influence of cooling wheel temperature on ribbon formation. Nusselt's correlation is used for the first time for selecting a convective heat transfer coefficient between rotating wheel and surrounding air. This approach assists in predicting the conditions at which a continuous/broken/no ribbon formation is obtained during the process. The model could predict whether the ribbon to be obtained is amorphous or non-amorphous before the experiment is actually performed at a set of process conditions. Various internal and external conditions of the cooling wheel are tested, and they show little influence on the ribbon thickness up to 0.5 s (10 rotations). Broken and nonamorphous ribbons are obtained for poor cooling conditions of the wheel with increase in time of cast from 0.5 s to 1 s (20 rotations). Amorphous ribbon with uniform thickness can be obtained for a wheel of 20 mm wall thickness, when the inner and outer surfaces of the cooling wheel are maintained at a temperature of at least 300 K.     

基于FX2N-10GM定位模块的圆台磨床数控系统

利用三菱FX2N-10GM定位模块,FX2N系列可编程序控制器(PLC)和交流伺服电机的组合,能对磨头的位置实现有效控制。实际应用证明该系统提高了圆台磨床的准确性和灵活性。     

冷却速度对快淬Fe-Si-B-Cu合金结构和磁性能的影响

采用单辊旋淬法,以不同的轮辊转速(50、40、30和25 m/s)制备高Fe含量Fe_(82.65)Cu_(1.35)Si_2B_(14)非晶合金薄带,研究了冷却速度对快淬合金结构和性能的影响.结果表明:随冷却速度的降低,淬态Fe_(82.65)Cu_(1.35)Si_2B_(14)合金的条带厚度逐渐增大,合金由完全的非晶态结构转变为非晶与纳米晶的混合结构;同时,随冷却速度的降低,一次晶化温度下降,材料的饱和磁感应强度逐渐增加,在轮辊转速为25 m/s时,淬态合金的饱和磁感应强度达到1.4 T.     

Fabrication and new electrochemical properties of nanoporous Cu by dealloying amorphous Cu–Hf–Al alloys

To produce monolithic nanoporous Cu (NPC) ribbons with good mechanical integrity, we investigate chemical dealloying behavior of an amorphous Cu_52.5Hf₄₀Al_7.5 alloy with good mechanical properties by immersion in 0.5 M HF solution for different times. With the design concept of adding ductile amorphous supporter to NPC ribbons, an amorphous alloy-containing interlayer with a certain thickness is successfully fabricated in the NPC ribbon by controlling dealloying time to ensure the good bendability of the dealloyed product. New electrochemical properties of the obtained NPC ribbon are further developed. The current signal and the specific capacitance of the NPC-supported MnO₂ composite electrode are remarkably enhanced as compared to those of pure MnO₂ powders. NPC substrate with large specific surface areas and excellent electrical conductivity can effectively promote the morphological change of MnO₂ from globular particles to nanoflakes for larger specific surface area and improve the utilization of MnO₂ surface active sites, which reveal new electrochemical properties of NPC in a potential application for supercapacitor composite electrodes.     

带厚对FeCuNbSiB纳米晶铁芯性能的影响

采用标称成分为Fe73.5Cu1Nb3Si15.5B7(原子百分数)、带厚分别为18 μm、22 μm和26 μm的带材制成环形铁芯,经过560℃保温1h热处理后测试其性能,发现铁芯损耗随带材厚度的减小而降低,实验中用18μm和22 μm厚带材制备的铁芯与在共模电感方面处于国际领先地位的VAC公司生产的同规格铁芯在电感...     

伺服阀科学使用的研究

分析伺服阀零位流量增益、零位压力增益、零位流量压力增益系数、零位内泄漏流量的重要作用,并利用伺服阀测试曲线说明阀芯、阀套锐边的磨损是导致伺服阀零位特性下降和零位内泄漏流量增加的主要原因。提出根据不同工况,将零位特性较差的伺服阀更换使用位置,不仅可以降低设备维护成本,同时可保障伺服液压系统性能和产品质量。