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基于BP算法的Ti-Fe-Mo-Mn-Nb-Zr系钛合金成分优化 总被引:4,自引:0,他引:4
研究了不同成分的Ti Fe Mo Mn Nb Zr合金的压缩强度、硬度及其在Hank’s人工体液中的耐腐蚀性能 ,得到了高压缩强度、硬度与牙本质相近的钛合金。在综合考虑钛合金成本、力学性能及耐腐蚀性能的基础上 ,采用BP神经网络建立了钛合金中的元素质量分数与硬度之间的关系 ,并通过实验进行了验证 ,预测结果与实验测定结果的对比是令人满意的。在保证性能的基础上 ,利用训练好的BP网络结构对材料的成分进行优化 ,以减少贵重元素的加入量。 相似文献
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Artificial neural networks have been widely used to predict the mechanical properties of alloys in material research.This study aims to investigate the implicit relationship between the compositions an... 相似文献
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This paper presents recent developments of a simplified finite element method called the inverse approach (IA) for the estimation of large elastoplastic strains and thickness distribution in tube hydroforming. The basic formulation of the IA, proposed by Guo et al. (1990), has been modified and adapted for the modeling of three-dimensional tube hydroforming problems in which the initial geometry is a circular tube expanded by internal pressure and submitted to axial feed at the tube ends. The application of the IA is illustrated through the analyses of numerical applications concerning the hydroforming of axisymmetric bulge, made from aluminum alloy 6061-T6 tubing, the hydroforming of square section hollow component and the hydroforming of a free Tee extrusion from welded low carbon steel LCS-1008 tubing. Verifications of the obtained results have been carried out using experimental results together with the classical explicit dynamic incremental approach using ABAQUS® commercial code to show the effectiveness of our approach. 相似文献
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带钢在退火炉内进行长时间加热的过程中,由于炉内温度、张力以及带钢运行速度等变量间具有多重相关性且存在生产数据噪声,从而难以准确预测炉内带钢的延伸量。本文提出了一种基于遗传算法的BP神经网络理论(GA-BP神经网络)与最小二乘支持向量机(LSSVM)理论相结合的算法用于目标函数拟合,该算法兼顾最小二乘支持向量机的全局与局部拟合能力,有效避免算法陷入局部最优的缺点,利用改进的BP神经网络算法优化选择LSSVM 模型的惩罚因子和核函数参数,以避免人为选择参数的盲目性,使LSSVM具有更好的泛化能力和预测精度。将该方法应用到退火炉内带钢的延伸量预测,通过现场生产数据仿真模拟进行非线性函数估计,结果表明:本文所提出的方法具有良好的预测精度,可以应用于实际生产。 相似文献
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采用热重分析、XRD和SEM等方法研究Ti-Cr合金(0≤w(Cr)≤25%)从室温至1723K的非等温氧化行为及氧化膜的微观结构,探讨Cr元素对Ti-Cr合金抗氧化能力的影响机制。结果表明:当Cr含量小于某一临界值wC时,随着Cr含量的增加合金的抗氧化能力降低;当Cr含量高于wC时,随着Cr含量的增加合金的抗氧化能力提高;当温度高到1000K时,Ti-Cr合金的氧化仍符合抛物线规律,且主要发生钛的氧化;Ti-Cr合金氧化后基体中存在氧扩散层,氧化膜主要为金红石型TiO2,内层氧化膜出现富Cr现象,Cr氧化物的析出提高了Ti-Cr合金的抗氧化能力。金属和合金的着火是一个快速非等温氧化的过程,预测了Ti-Cr合金着火阶段的氧化机制。 相似文献
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REN Yuping ZHANG Haifeng SUN Wensheng WANG Aimin LI Hong HU Zhuangqi HAO Shiming LI Hongxiao 《稀有金属(英文版)》2007,26(5):504-507
The liquidus univariant lines of the Fe-Nb-B ternary system have been thermodynamically calculated by means of CALPHAD method and Fe-based thermodynamic data. It is found that there are two eutectic reactions in the Fe-rich corner,that is,(1) L(Fe-3Nb-15B) →α+γ+ M2B (1430 K),and (2) L(Fe-10Nb-27B) → FeB + Lc14 + M2B (1575 K). Moreover,the eutectic points are very close to the compositions with high glass forming ability determined experimentally. This means that it is feasible to design the compositions of multicomponent bulk metallic glasses by looking for the eutectic points in the Fe-Nb-B system by means of thermodynamic calculation. 相似文献
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采用反向传播(back propagation,BP)人工神经网络(artificial aeural network,ANN)和遗传算法建立了激光熔覆层形貌质量(熔覆层高度、宽度及稀释率)与激光功率、送粉速率和扫描速率之间的遗传神经网络预测模型.设计正交试验得到预测模型训练样本数据,并在正交试验的基础上,用极差分析法分析了各加工参数对熔覆层形貌质量各个指标的影响规律.经过试验验证,遗传神经网络模型预测值与试验实测值误差不大于4.6%.结果表明,运用该模型可以为准确的选择镍基高温合金激光熔覆参数提供一定参考,从而有利于提高镍基高温合金激光熔覆层形貌质量. 相似文献
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E. A. Carrera J. H. Ramírez-Ramírez F. A. Pérez-González J. A. González I. Crespo I. Braceras 《International Journal of Cast Metals Research》2017,30(3):171-179
Liquid aluminium alloys affect the moulds, by formation of intermetallic layers at their surface; such attack is enhanced by the flow of the molten metal on the surface of the tooling. Metal tooling are used to promote high heat transfer rates and increase the solidification rate to enhance mechanical properties in cast pieces, but the damage to their surface affects their quality and increases the production costs due to the need to repair them. This work presents the results of a series of studies conducted to evaluate the attack produced by molten aluminium on samples of iron based materials commonly used in the manufacture of dies and moulds. The studies were conducted in a machine that imposes a rotating movement to experimental specimens to simulate the flow of liquid metal. The damage observed in the samples was compared to that experienced by tooling in the melt shop. 相似文献
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Intermetallic alloys based on gamma titanium aluminide 总被引:4,自引:0,他引:4
Titanium-aluminide alloys based on TiAl have an excellent potential to become one of the most important aerospace materials because of their low density, high melting temperature, good elevated-temperature strength and modulus retention, high resistance to oxidation and hydrogen absorption, and excellent creep properties. The chief roadblock to their application is poor ductility at low to intermediate temperatures that results in low fracture toughness and a fast fatigue-crack growth rate. During the last several years, a great deal of effort has been made to improve these ductile properties. These endeavors have met with some success through chemistry modification and microstructure control. 相似文献
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Direct production of alloys based on titanium aluminides has been demonstrated via two-step aluminothermic reduction of titanium tetrachloride (TiCl4). In the first step, TiCl4 is reduced by aluminium to titanium trichloride (TiCl3) at a temperature below the boiling point of TiCl4 and at 1 atm under argon. The resulting TiCl3 intermediate product is then reacted with aluminium at temperatures up to around 1000 °C, leading to synthesis of a Ti–Al alloy powder. In addition, alloying additives such as Nb, Cr, Mo and C have also been included in various concentrations. 相似文献
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Optimization of pulsed TIG cladding process of stellite alloy on carbon steel using RSM 总被引:2,自引:0,他引:2
F. Madadi 《Journal of Alloys and Compounds》2012,510(1):71-77
Stellite 6 is a cobalt-base alloy which is resistant to wear and corrosion and retains these properties at high temperatures. The exceptional wear resistance of Stellite 6 is mainly due to the unique inherent characteristics of the hard carbides dispersed in a Co-Cr alloy matrix. In this study, pulsed tungsten inert gas (TIG) cladding process was carried out to deposit Stellite 6 on plain carbon steel plate. The beneficial effects of this cladding process are low heat input, low distortion, controlled weld bead volume, less hot cracking tendency, less absorption of gases by weld pool and better control of the fusion zone. The dilution effect is a key issue in the quality of cladded layers and, in this regard, the pulsed current tungsten inert gas (PCTIG) was performed to decrease excess heat input and melting of substrate. This paper deals with the investigation of the hardness and dilution ratio by experimental study and mathematical modeling. The experiments were conducted based on four-factor, five-level central composite rotatable design. The second-order regression method was developed to study the correlations. The developed models were checked for their adequacy and significance by ANOVA analysis and confirmation tests were carried out to check the accuracy of predicted values. 相似文献
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设计了一种基于电流变液的触觉显示器,并对该触觉显示器的触摸敏感性进行了研究.该显示器具有5×5个显示单元,其表面是一层导电弹性薄膜,作为电极为电流变液提供电场.对该触觉显示器的表面触摸力响应实验研究表明,该触觉显示器显示能力持久且具有良好的重复使用性.通过监测通过电流变液层的电流变化,可以有效地探测出施加于触觉显示器表面的外力的变化.这个结果对进一步将该触觉显示器改造成兼具传感与作动功能于一体的新型阵列式触觉显示器具有极大的意义. 相似文献