绿色再制造工程及其在我国主要机电装备领域产业化应用的前景*

阐述了装备再制造工程的内涵与特征，提出了今后需要研发的再制造关键技术与系统装备，论述了再制造今后的产业化应用方向，阐述了推进我国再制造产业发展的政策建议与措施。结果表明：绿色再制造工程是废旧产品高技术修复改造的产业化，是现代服务业的重要组成，再制造工程今后可在我国汽车领域、工程机械领域、化工冶金领域、国防装备等领域推广应用并形成产业化。在新世纪发展再制造工程并推进其产业化发展是构建循环经济和建设节约型社会的重要途径之一。     

装备再制造设计及其内容体系

装备再制造工程是实现装备资源节约与环境保护的重要手段,科学的装备再制造设计是提高装备再制造效益及提高装备再制造性的关键方法,也是再制造工程的重要研究领域。文中指出装备再制造设计面向装备再制造的全过程,包括面向生产的设计、面向回收物流的设计和面向装备服役的设计3部分内容,提出了再制造设计研究的范围、对象、目的、手段及时域,明确了其任务和目标,构建了包含再制造设计基础、再制造技术与工艺设计、再制造管理设计的装备再制造设计理论与技术体系,并确立了装备再制造设计要采取全系统、全寿命、全费用和绿色化的基本观点,给出了今后发展的装备再制造性设计与评价、再制造生产系统规划设计、再制造逆向物流优化设计、再制造信息管理与应用设计等4个关键领域的研究目标和内容。     

新时代中国特色再制造的创新发展

再制造是机电产品资源化循环利用的最佳途径之一,是推进资源节约和循环利用的重要技术支撑。文中回顾了维修工程向表面工程到再制造工程的发展历程,阐述了中国特色再制造独有的技术模式和效益模式;总结了中国特色再制造在面向国家战略、围绕装备需求、推动人才培养等方面取得的成绩;重点提出了新时代中国特色再制造在推进绿色发展,促进装备战斗力再生,构建一流学科等方面的创新发展方向。     

2017中国内燃机再制造企业赴欧考察交流圆满成功

为积极响应国家“一带一路”建设的倡议,深入贯彻落实《内燃机再制造推进计划》的五大工程,实现发展目标,促进内燃机再制造产业的发展.中内协和内燃机再制造产业联盟组织了2017中国内燃机再制造企业赴欧考察交流活动,本次活动主要是加强对欧洲再制造产业发展模式、先进再制造技术、再制造专用装备应用、再制造技术标准体系建设、当地的政策法规等重点领域的认识,促进中欧企业在再制造领域的交流与合作,释放中国内燃机再制造企业的产能,获得更大的经济效益和社会效益.     

高速电弧喷涂技术在装备维修与再制造工程领域的研究应用现状

高速电弧喷涂技术是一种优质、高效、低成本的再制造工程关键技术,综述了高速电弧喷涂技术的发展,及其分别在汽车发动机再制造、装备钢结构件防腐、火电厂锅炉管道受热面防护领域的研究应用现状,并展望了高速电弧喷涂技术在维修与再制造工程中的发展趋势.     

第二届全国装备再制造工程学术会议10月在济南举行

由中国工程机械学会维修工程分会、中国设备管理协会再制造技术委员会与工程机械维修委员会、装备再制造技术国防科技重点实验室联合主办的第二届全国装备再制造工程学术会议今年10月将在济南召开。这次会议的主题是绿色再制造与绿色维修。它体现了贯彻落实科学发展观，构建循环经济，建设资源节约型和环境友好型社会的要求，符合我国经济可持续发展的方向。因而受到国家发改委环境与资源利用司，国家科技部高新技术发展与产业化司、国家自然科学基金委、中国工程院机械与运载工程学部，以及中国重汽集团有限公司等单位的大力支持。     

我国再制造工程及其产业发展

再制造是维修工程和表面工程发展的高级阶段,是先进制造的重要组成,是废旧产品高技术修复、改造的产业化。近年来,中国的再制造发展迅速,已在再制造的政策法规、产业实践及基础研究方面成绩斐然。本文阐述了中国自主创新再制造的模式及内涵,综述了我国再制造质量控制关键技术,分析了国内再制造工程产业发展的前沿问题。     

装备再制造工程学科的建设和发展

阐述了装备再制造工程的内涵、国内外研究现状以及装备再制造工程学科体系。重点从装备再制造工程特定的研究对象、坚实的理论基础、独立的研究内容、具有特色的研究方法与关键技术、国家重点实验室的建立等5个方面论述了装备再制造工程这一新兴学科的形成。指出再制造工程是先进制造工程的重要组成部分,是表面工程等先进技术在废旧机电产品上的综合应用,也是对维修工程的继承和发展。装备再制造工程学科及装备再制造技术国防科技重点实验室的建设必将促进装备维修保障的新发展,加速旧武器装备的廷寿和升级改造,对军队现代化建设将起到重要作用。     

2017中国内燃机再制造企业赴欧考察交流圆满成功

为积极响应国家"一带一路"建设的倡议,深入贯彻落实《内燃机再制造推进计划》的五大工程,实现发展目标,促进内燃机再制造产业的发展。中内协和内燃机再制造产业联盟组织了2017中国内燃机再制造企业赴欧考察交流活动,本次活动主要是加强对欧洲再制造产业发展模式、先进再制造技术、再制造专用装备应用、再制造技术标准体系建设、当地的政策法规等重点领域的认识,促进中欧企业在再制造领域的交流与合作,释放中国内燃机再制造     

再制造工程及其失效分析

再制造工程是废旧产品高技术修复、改造的产业化,也是循环经济4R准则中最活跃的形式和首选途径.再制造工程具有节能节材、环境保护及解决就业等重要作用.再制造工程与失效分析关系密切,失效分析是再制造工程的基础和依据,再制造工程是失效分析的结果与发展.结合重载车辆侧减速器主动轴、重载车辆扭力轴、飞机发动机压气机叶片等关键零部件的失效分析和再制造工程实例,阐述了失效分析和再制造工程的相互关系及其对在工程中的联合作用.     

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.     

新型的治疗阿尔茨海默氏症药物(1-二甲基磷酰基-2,2,2-三氯)-乙基-1-醇烟酸醋对体外神经细胞的作用

目的: 观察本实验室合成的一种治疗阿尔茨海默氏症(AD)的药物(1-二甲基磷酰基-2, 2, 2 -三氯)-乙基^-1-醇烟酸醋(NMF),对体外培养的皮层神经细胞活性的影响以及对海人藻酸(KA)所致的神经损伤的保护作用。方法: 采用体外培养皮层神经元的方法,解剖分离 15 d胚胎小鼠皮层神经细胞, 接种于 96孔板,48 h 后加药并培养 72 h,以 MIT 法 观察 NMF 对小鼠皮层神经细胞活性的影响;同时将接种于 24 孔板的细胞预先给予 NMF,d 3 时加或不加KA处理后,以台盼蓝染色鉴别并计数死、活细胞,可得出细胞的存活率。结果: NMF 明显促进胎鼠皮层神经元活性,其中 NMF1、0. 1、10nmol·L^-1促进神经元活性增殖率分别高达 34.7%、37.4%、36. 7%, NMF 明显促进正常胎鼠皮层神经元存活卒,与对照组比较,10nmol·L^-1 NMF 对皮层神经元的存活率分别提高 39.3%、73.5%。 NMF能显著 对抗 KA 所致的神经元损伤,与 KA 损伤组相比, NMF0.1、10、10nmol·L^-1对损伤皮层神经元的保护率分别为 77.30%、80.10%、84.15%。结论: NMF 明 显促进胎鼠皮层神经元的洁性、提高正常皮层神经元,的存活卒,并能有效地保护KA所致的神经元损伤,提示 NMF 是一种很有潜力的治疗 AD 的药物。     

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).     

Three-Dimensional Growth of Coherent Ferrite in Austenite: A Molecular Dynamics Study

Coherent second phase often exhibits anisotropic morphology with specifi c orientations with respect to both the second and the matrix phases. As a key feature of microstructure, the morphology of the coherent particles is essential for understanding the second-phase strengthening eff ect in various industrial alloys. This letter reports anisotropic growth of coherent ferrite from austenite matrix in pure iron based on molecular dynamics simulation. We found that the ferrite grain tends to grow into an elongated plate-like shape, independent of its initial confi guration. The fi nal shape of the ferrite is closely related to the misfi t between the two phases, with the longest direction and the broad facet of the plate being, respectively, consistent with the best matching direction and the best matching plane calculated via the Burgers vector content(BVC) method. The strain energy calculation in the framework of Eshelby's inclusion theory verifi es that the simulated orientation of the coherent ferrite is energetically favorable. It is anticipated that the BVC method will be applicable in analysis of anisotropic growth and morphology of coherent second phase in other phase transformation systems.     

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.     

Directional Growth of Tin Crystals Controlled by Combined Solute Concentration Gradient Field and Static Magnetic Field

A new method was introduced to achieve directional growth of Sn crystals. Microstructures in liquid(Pb)/liquid(Sn) diffusion couples were investigated under various static magnetic fields. Results show that the β-Sn crystals mainly reveal an irregular dendritic morphology without or with a relatively low static magnetic field(B0.3 T). When the magnetic field is increased to 0.5 T, the β-Sn dendrites close to the final stage of growth begin to show some directional character. With a further increase in the magnetic field to a higher level(0.8–5 T), the β-Sn dendrites have an enhanced directional growth character, but the dendrites show a certain deflection. As the magnetic field is increased to 12 T, the directional growth of the β-Sn dendrites in the center of the couple is severely destroyed. The mechanism of the directional growth of the β-Sn crystals and the deflection of the β-Sn crystals with the application of static magnetic field was tentatively discussed.