塑胶工件硫化过程的强鲁棒智能控制策略研究（英文）

针对不确定性导致的塑胶工件硫化过程难于实施数学建模精准控制,探讨了一种强鲁棒智能控制策略。剖析了胶塑工件的硫化效应影响因素,总结了塑胶工件硫化过程的控制论特性,研究了与硫化过程相匹配的强鲁棒控制策略,并构造了一种基于仿人智能的强鲁棒控制算法。以典型二阶滞后硫化等效模型为例,基于Matlab软件平台的仿真对比研究,验证了研究控制策略的强鲁棒性能。仿真结果表明:提出的控制策略可对塑胶工件硫化过程实施优化控制,所构造的智能控制算法是合理、可行与有效的。     

复杂塑胶加工件成形过程的强鲁棒性控制策略

针对塑胶加工件成型过程中保温时间、注射压力与过程温度难于实施精确控制的问题,探讨了基于多模态控制的强鲁棒性策略。剖析了过程存在的控制难题,总结了过程的控制论特性,基于控制策略的对比研究,探讨了基于仿人智能的强鲁棒性控制策略,构造了塑胶加工件成形过程的多模态控制算法。以过程温度控制为例,仿真验证了提出的强鲁棒性控制策略的良好动静态控制品质。实验仿真结果表明：该强鲁棒性控制策略是合理可行的。     

复杂不确定性过程中基于智能的多模态控制策略

数学模型难以描述复杂不确定性的过程.为了避免复杂不确定性过程控制中用数学范式建模与控制的困境,探索了一种基于无模型的智能控制策略.基于分解协调原理,对过程控制的难点进行了剖析,总结了底层复杂不确定性过程的控制论特征,研究了面向独立子过程的无模型多模态智能控制策略,并构造了一种多模态控制算法.实验仿真的响应曲线表明:基于仿人智能控制的多模态控制策略能获得预期的良好控制品质.研究结果表明:提出的多模态控制策略是合理可行的.     

Control Strategy of Rigidity Based on Intelligence Fusion for Plastic & Rubber Workpeice

针对塑胶硫化过程控制的复杂性,提出了一种基于仿人智能的融合控制策略.剖析了硫化过程中的工艺控制难点,总结了硫化过程的控制论特性,研究了控制策略,构建了控制模型,讨论了控制算法.基于工程实现,搭建了一个工控机控制系统.系统实验测试结果显示,提出的控制策略及控制算法的鲁棒性强、稳定性好和控制精度高.研究结果表明提出的智能融合控制策略是可行与有效的.     

复杂不确定性过程中基于智能的多模态控制策略（英文）

数学模型难以描述复杂不确定性的过程。为了避免复杂不确定性过程控制中用数学范式建模与控制的困境,探索了一种基于无模型的智能控制策略。基于分解协调原理,对过程控制的难点进行了剖析,总结了底层复杂不确定性过程的控制论特征,研究了面向独立子过程的无模型多模态智能控制策略,并构造了一种多模态控制算法。实验仿真的响应曲线表明:基于仿人智能控制的多模态控制策略能获得预期的良好控制品质。研究结果表明:提出的多模态控制策略是合理可行的。     

塑胶工件刚度的智能融合控制策略(英文)

针对塑胶硫化过程控制的复杂性,提出了一种基于仿人智能的融合控制策略。剖析了硫化过程中的工艺控制难点,总结了硫化过程的控制论特性,研究了控制策略,构建了控制模型,讨论了控制算法。基于工程实现,搭建了一个工控机控制系统。系统实验测试结果显示,提出的控制策略及控制算法的鲁棒性强、稳定性好和控制精度高。研究结果表明提出的智能融合控制策略是可行与有效的。     

基于模糊免疫PID控制的AGC控制系统

针对变截面板簧轧机厚度自动控制系统这一类非线性、时变的复杂系统,利用模糊算法的强鲁棒性以及根据人类免疫系统而设计的免疫算法,提出了模糊免疫PID控制方法.这种控制方法不需要建立控制对象精确的数学模型,是一种具有鲁棒性强、实时性强的智能控制策略.仿真实验证明:在模糊免疫PID控制器的控制下的AGC系统具有了高响应速度,超调量小,抗干扰能力强的响应特性.     

基于积分滑模的压机液压缓冲垫负载力控制

针对压机液压缓冲垫负载力控制问题,提出一种基于积分滑模的鲁棒控制策略。该方法利用滑模控制鲁棒性强的优点,实现了缓冲液压垫负载力的精确跟踪控制,并且对系统中的参数不确定性和外部干扰具有较好的抑制作用。理论分析与仿真结果对比验证了该控制算法的有效性。     

基于动力学补偿的并联机器人鲁棒轨迹跟踪控制研究

针对6-DOF并联机器人系统存在动力学建模误差和外界不确定性因素干扰的问题,提出了一种基于动力学补偿的并联机器人鲁棒轨迹跟踪控制策略。在充分研究了机器人系统动力学模型特点的基础上,基于Lyapunov方法获得了并联机器人的鲁棒控制率,提出了一种鲁棒轨迹跟踪控制方法,采用逆动力学对内回路进行补偿,外回路采用PD控制,然后对并联机器人进行了鲁棒控制器的设计,最后通过MATLAB进行了系统的轨迹跟踪控制仿真分析。仿真结果表明:当系统存在外界周期干扰的状况时,系统轨迹跟踪误差仍然一致终值有界,在一定程度上提高了系统的鲁棒稳定性。     

改进的PSO算法及其在控制系统参数整定中的应用(英文)

针对传统PID控制对非线性、强耦合控制系统的控制效果不佳,参数整定难度大的情况,基于改进的PSO算法,设计了一种HSIC控制器。该设计借助改进的粒子群算法对控制器参数整定进行了优化研究,基于粒子群算法,借鉴遗传算法中操作因子特性,提出了一种具有遗传思想的改进粒子群算法。在Matlab环境下,通过对标准函数的仿真实验测试,验证了该改进算法的优越性。利用Simulink工具对所设计的2种控制器进行了仿真比较研究,仿真实验表明,所设计的仿人智能控制器具有较好的控制品质,有比较好的可实现性。研究表明,整定后的控制器可以满足受控系统的控制品质要求。     

Effects of Post-weld Heat Treatment on Microstructure,Mechanical Properties and the Role of Weld Reinforcement in 2219 Aluminum Alloy TIG-Welded Joints

In as-welded state, each region of 2219 aluminum alloy TIG-welded joint shows diff erent microstructure and microhardness due to the diff erent welding heat cycles and the resulting evolution of second phases. After the post-weld heat treatment, both the amount and the size of the eutectic structure or θ phases decreased. Correspondingly, both the Cu content in α-Al matrix and the microhardness increased to a similar level in each region of the joint, and the tensile strength of the entire joint was greatly improved. Post-weld heat treatment played the role of solid solution strengthening and aging strengthening. After the post-weld heat treatment, the weld performance became similar to other regions, but weld reinforcements lost their reinforcing eff ect on the weld and their existence was more of an adverse eff ect. The joint without weld reinforcements after the post-weld heat treatment had the optimal tensile properties, and the specimens randomly crack in the weld zone.     

The First Phase of the SRIF Industrialized Base in ＂West Area＂ Has Been Put into Operation

After nearly two years＇ tense construction, the first phase of industrialized base of Shenyang Research Institute of Foundry （SRIF）, located at the Tiexi Casting and Forging Industrial Park in the west of Tiexi District, has now been completed and formally put into operation.     

Thermodynamics Study on the Decomposition of Chromite with KOH

Institute of Process Engineering, Chinese Academy of Sciences, China, has proposed a method for oxidative leaching of chromite with potassium hydroxide. Understanding the mechanism of chromite decomposition, especially in the potassium hydroxide fusion, is important for the optimization of the operating parameters of the oxidative leaching process. A traditional thermodynamic method is proposed and the thermal decomposition and the reaction decomposition during the oxidative leaching of chromite with KOH and oxygen is discussed, which suggests that chromite is mainly destroyed by reactions with KOH and oxygen. Meanwhile, equilibrium of the main reactions of the above process was calculated at different temperatures and oxygen partial pressures. The stable zones of productions, namely, K2CrO4 and Fe2O3, increase with the decrease of temperature, which indicates that higher temperature is not beneficial to thermodynamic reactions. In addition, a comparison of the general alkali methods is carried out, and it is concluded that the KOH leaching process is thermodynamically superior to the conventional chromate production process.     

Influence of Heat Treatment on Damping Behaviour of the Magnesium Wrought Alloy AZ61

The effect of isochronal heat treatments for 1h on variation of damping, hardness and microstructural change of the magnesium wrought alloy AZ61 was investigated. Damping and hardness behaviour could be attributed to the evolution of precipitation process. The influence of precipitation on damping behaviour was explained in the framework of the dislocation string model of Granato and Lücke.     

Effect of Rare Earth Doping on Impedance,Modulus and Conductivity Properties of Multiferroic Composites:0.5(BiLa_xFe_(1-x)O_3)–0.5(PbTiO_3)

The Lanthanum-doped bismuth ferrite–lead titanate compositions of 0.5(Bi LaxFe1-xO3)–0.5(Pb Ti O3)(x = 0.05,0.10,0.15,0.20)(BLxF1-x-PT) were prepared by mixed oxide method.Structural characterization was performed by X-ray diffraction and shows a tetragonal structure at room temperature.The lattice parameter c/a ratio decreases with increasing of La(x = 0.05–0.20) concentration of the composites.The effect of charge carrier/ion hopping mechanism,conductivity,relaxation process and impedance parameters was studied using an impedance analyzer in a wide frequency range(102–106Hz) at different temperatures.The nature of Nyquist plot confirms the presence of bulk effects only,and non-Debye type of relaxation processes occurs in the composites.The electrical modulus exhibits an important role of the hopping mechanism in the electrical transport process of the materials.The ac conductivity and dc conductivity of the materials were studied,and the activation energy found to be 0.81,0.77,0.76 and 0.74 e V for all compositions of x = 0.05–0.20 at different temperatures(200–300 °C).     

Quantitative Analysis of the Crystallographic Orientation Relationship Between the Martensite and Austenite in Quenching–Partitioning–Tempering Steels

The orientation relationships(ORs)between the martensite and the retained austenite in low-and medium-carbon steels after quenching–partitioning–tempering process were studied in this work.The ORs in the studied steels are identified by selected-area electron diffraction(SAED)as either K–S or N–W ORs.Meanwhile,the ORs were also studied based on numerical fitting of electron backscatter diffraction data method suggested by Miyamoto.The simulated K–S and N–W ORs in the low-index directions generally do not well coincide with the experimental pole figure,which may be attributed to both the orientation spread from the ideal variant orientations and high symmetry of the low-index directions.However,the simulated results coincide well with experimental pole figures in the high-index directions{123}_(bcc).A modified method with simplicity based on Miyamoto’s work was proposed.The results indicate that the ORs determined by modified method are similar to those determined by Miyamoto’method,that is,the OR is near K–S OR for the low-carbon Q–P–T steel,and with the increase of carbon content,the OR is closer to N–W OR in medium-carbon Q–P–T steel.     

Growth Kinetics of Single Inclusion Particle in Molten Melts

On the basis of the single-particle framework, a new theory on inclusion growth in metallurgical melts is developed to study the kinetics of inclusion growth on account of reaction and collision. The studies show that the early growth of inclusion depends on reaction growth and Brawnian motion collision, and where the former is decisive, the late growth depends on turbulence collision and Stokes＇ collision, and where the former is dominant; collision growth is very quick during the smelting process, lessened in the refining process, but nearly negligible in the continuous casting process.     

Theoretical Analysis for the Motion and Temperature of Melt Droplets in Spray Degassing Process

The motion of melt droplets in spray degassing process was analyzed theoretically. The height of the treatment tank in spray degassing process could be determined by the results of theoretical calculation of motion of melt droplets. To know whether the melt droplets would solidify during spraying process, the balance temperature of melt droplets was also theoretically analyzed. Then proof experiments for theoretical results about temperature of melt droplets were carried. In comparison, the experimental results were nearly similar to the calculation results.     

Using Finite Element and Contour Method to Evaluate Residual Stress in Thick Ti-6Al-4V Alloy Welded by Electron Beam Welding

This work was to reveal the residual stress profile in electron beam welded Ti-6Al-4V alloy plates(50 mm thick) by using finite element and contour measurement methods.A three-dimensional finite element model of 50-mmthick titanium component was proposed,in which a column–cone combined heat source model was used to simulate the temperature field and a thermo-elastic–plastic model to analyze residual stress in a weld joint based on ABAQUS software.Considering the uncertainty of welding simulation,the computation was calibrated by experimental data of contour measurement method.Both test and simulated results show that residual stresses on the surface and inside the weld zone are significantly different and present a narrow and large gradient feature in the weld joint.The peak tensile stress exceeds the yield strength of base materials inside weld,which are distinctly different from residual stress of the thin Ti-6Al-4V alloy plates presented in references before.     

Microstructures and Tensile Properties of Ultrafine-Grained Ni–(1–3.5) wt% SiC_(NP) Composites Prepared by a Powder Metallurgy Route

Silicon carbide nanoparticle-reinforced nickel-based composites(Ni–Si CNP),with a Si CNPcontent ranged from1 to 3.5 wt%,were prepared using mechanical alloying and spark plasma sintering.In addition,unreinforced pure nickel samples were also prepared for comparative purposes.To characterize the microstructural properties of both the unreinforced pure nickel and the Ni–Si CNPcomposites transmission electron microscopy(TEM) was used,while their mechanical behavior was investigated using the Vickers pyramid method for hardness measurements and a universal tensile testing machine for tensile tests.TEM results showed an array of dislocation lines decorated in the sintered pure nickel sample,whereas,for the Ni–Si CNPcomposites,the presence of nano-dispersed Si CNPand twinning crystals was observed.These homogeneously distributed Si CNPwere found located either within the matrix,between twins or on grain boundaries.For the Ni–Si CNPcomposites,coerced coarsening of the Si CNPassembly occurred with increasing Si CNPcontent.Furthermore,the grain sizes of the Ni–Si CNPcomposites were much finer than that of the unreinforced pure nickel,which was considered to be due to the composite ball milling process.In all cases,the Ni–Si CNPcomposites showed higher strengths and hardness values than the unreinforced pure nickel,likely due to a combination of dispersion strengthening(Orowan effects) and particle strengthening(Hall–Petch effects).For the Ni–Si CNPcomposites,the strength increased initially and then decreased as a function of Si CNPcontent,whereas their elongation percentages decreased linearly.Compared to all materials tested,the Ni–Si CNPcomposite containing 1.5% Si C was found more superior considering both their strength and plastic properties.