TCA钛合金惯性摩擦焊接头温度场分析

通过对惯性摩擦焊过程摩擦机理的分析，讨论了TC4钛合金惯性摩擦焊工艺参数与焊接过程界面摩擦扭矩及能量转换的关系，采用热电偶对TC4钛合金惯性摩擦焊焊接过程接头温度分布进行了测试，焊接接头沿径向温度梯度很大，中心温度接近800℃，边缘达1360℃。通过显微组织分析验证了测量结果，焊缝中心为细小的等轴组织，沿径向晶粒长大飞边为针片状组织。     

TC4钛合金高转速惯性摩擦焊接头组织及性能分析

采用高转速(3500～4300 r/min)惯性摩擦焊方法焊接TC4钛合金,观察了不同焊接工艺条件下焊接接头的显微组织,讨论了高转速条件下惯性摩擦焊接接头组织的形成机理,分析了焊接接头的性能.结果表明,TC4钛合金惯性摩擦焊焊接接头的形状呈"V"字型,焊缝区和热影响区的组织特征与低转速条件下的显微组织一致.焊缝组织沿径向变化,心部为细小的等轴晶,向外逐渐过渡为片状组织;焊缝区的硬度高于母材和热影响区;接头拉伸试样断裂于母材.     

转速对TC4摩擦焊接头温度分布与微观组织的影响

采用连续驱动摩擦焊技术对TC4钛合金进行了连接。利用热电偶测温及金相显微镜观察等分别研究了不同转速下TC4钛合金焊接接头界面区的温度分布及微观组织变化。结果表明,焊接界面的升温速率和峰值温度均随转速增加而增大,初始摩擦阶段升温速率最高达762℃/s,峰值温度最高达1041℃,且转速越高,焊接界面温度沿径向分布的均匀性越好。TC4摩擦焊接头焊合区组织为网篮状组织,热力影响区为双态组织。网篮状组织随转速增加而明显粗化。     

金属的焊接性

20093043TC4钛合金高转速惯性摩擦焊接头组织及性能分析/赵红凯…//焊接.-2008(11):46~49采用高转速(3500~4300r/min)惯性摩擦焊方法焊接TC4钛合金,观察了不同焊接工艺条件下焊接接头的显微组织,讨论了高转速条件下惯性摩擦焊接接头组织的形成机理,分析了焊接接头的性能。结果表明,TC4钛合金惯性摩擦焊接头呈“V“形,焊缝区和热影响区的组织特征与低转速条件下的显微组织一致。焊缝组织沿径向变化,心部为细小的等轴晶,向外逐渐过渡为片状组织;焊缝区的硬度高于母材和热影响区;接头拉伸试样断裂于母材。图5表3参820093044高氮奥氏体不锈钢MIG焊接头的组织和性能/杜挽生…//焊接.-2008(12):25~29高氮钢焊接技术的研究是高氮钢研制和应用的关键技术之一。采用熔化极惰性气体保护焊方法对7mm和14mm厚的高氮钢进行了焊接,研究了焊接接头的组织和力学性能。结果表明,高氮钢MIG焊焊缝和热影响区的组织为奥氏体和少量的δ-铁素体,焊接接头强度与母材相当。7mm厚板MIG焊焊接接头具有较好的韧性,而14mm厚板热影响区韧性较低,其原因为经历多次焊接热循环导致敏化区的碳化物Cr23C6...     

金属的焊接性

20093043TC4钛合金高转速惯性摩擦焊接头组织及性能分析/赵红凯…//焊接.-2008(11):46~49采用高转速(3500~4300r/min)惯性摩擦焊方法焊接TC4钛合金,观察了不同焊接工艺条件下焊接接头的显微组织,讨论了高转速条件下惯性摩擦焊接接头组织的形成机理,分析了焊接接头的性能。结果表明,TC4钛合金惯性摩擦焊接头呈"V"形,焊缝区和热影响区的组织特征与低转速条件下的显微组织一致。焊缝组织沿径向变化,心部为细小的等轴晶,向外逐渐过渡为片状组织;焊缝区的硬度高于母材和热影响区;接头拉伸试样断裂于母材。图5表3参820093044高氮奥氏体不锈钢MIG焊接头的组织和性能/杜挽生…//焊接.-2008(12):25~29高氮钢焊接技术的研究是高氮钢研制和应用的关键技术之一。采用熔化极惰性气体保护焊方法对7mm和14mm厚的高氮钢进行了焊接,研究了焊接接头的组织和力学性能。结果表明,高氮钢MIG焊焊缝和热影响区的组织为奥氏体和少量的δ-铁素体,焊接接头强度与母材相当。7mm厚板MIG焊焊接接头具有较好的韧性,而14mm厚板热影响区韧性较低,其原因为经历多次焊接热循环导致敏化区的碳化物Cr23C6...     

TC4钛合金搅拌摩擦焊连接组织形貌研究

使用搅拌摩擦焊技术成功地实现了TC4(Ti-6Al-4V)钛合金的有效连接,并对焊接接头组织进行了研究.结合TC4钛合金搅拌摩擦焊的特点,分析了TC4钛合金搅拌摩擦焊接头焊合区的组织形貌及特征.结果表明:TC4钛合金搅拌摩擦焊接头焊合区组织为细密的等轴晶组织,焊接过程中焊缝最大温度并未超过相变温度,且经历了很大的塑性变形.焊缝与母材过渡区域存在大量α/β界面相及界面产物,α/β界面相及界面产物会对接头力学性能造成不良影响,应进行焊后热处理予以消除.     

TC4钛合金摩擦焊接头的力学性能及显微组织

对钛合金TC4（Ti-6Al-4V）摩擦焊接性能进行了较详细的试验分析。结合摩擦焊接参数的优化选择,叙述了该合金摩擦焊接过程的特点,讨论分析了其焊接接头的力学性能及焊合区的显微组织结构。试验结果表明,该合金具有良好的摩擦焊接性,在无特殊保护措施的条件下,优化工艺,可获得良好的焊接接头。由于TC4钛合金导热系数小,热塑性高,容易氧化,摩擦焊亦选用较小的规范参数。焊合区硬度略低于母材,拉伸度样断于母材,拉伸、冲击断口均表现出明显的韧性断裂特性。力学性能数据表明,用优化的规范参数,TC4钛合金可获得等强、等韧甚至超强、超韧于母材的摩擦焊接接头。TC4钛合金摩擦焊接接头焊合区组织为细密的网蓝状组织,焊合区与母材过渡区为双态组织。     

TC4钛合金线性摩擦焊接头组织和力学性能

文中阐述了线性摩擦焊的原理、特点,并针对TC4钛合金线性摩擦焊接头组织和力学性能进行了研究.对比分析TC4钛合金线性摩擦焊接头焊态和焊后热处理态的接头组织和力学性能.结果表明,焊接接头共分为母材、热力影响区和焊缝区三部分;TC4钛合金的接头(包括焊态和焊后热处理态)抗拉强度和屈服强度均达到母材的90%以上;焊缝中心的硬度值最高,焊后热处理能使接头的硬度分布更加均匀.     

振幅对线性摩擦焊接头组织和元素分布的影响

针对航空发动机整体叶盘常用的TC11和TC17钛合金,在线性摩擦焊设备上进行了试件焊接,对TC11/TC17钛合金线性摩擦焊接头进行了金相组织观察和电子探针测试,并测量了焊接过程的温度.结果表明,当其它工艺参数不变时,TC17侧焊合区的宽度随着振幅的减小而变宽,两侧热力影响区的组织沿着受力方向被拉长,而焊核区的组织为动态再结晶组织.Cr元素的浓度变化距离随着振幅的增加而增大.焊接过程的温度可达到1 200℃,超过了钛合金的β转变温度.     

采用Ni基合金为中间层的TC4钛合金扩散焊接工艺

采用Ni基非晶态合金作为中间层对TC4钛合金进行了不同工艺参数的真空搭接扩散焊试验,通过对接头性能测试及对接头微观组织分析,研究了扩散焊工艺参数对接头性能的影响规律.试验结果表明,焊接温度和保温时间对接头质量有很大的影响.在本试验条件下,TG4钛合金添加Ni基合金为中间层扩散焊的最佳焊接工艺为焊接温度1 020℃、焊接...     

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.     

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.     

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.     

The Mirror with Patterns of Auspicious Animals and Grapes——Exquisite cast mirror and the technology of surface tin-enrichment by rubbing-in and infiltration of tin-rich powder

<正>Bronze mirrors were used by the Chinese people before the introduction of the glass mirror.Only after it was replaced by the glass mirror did the bronze mirror gradually retreat from people's lives.Different styles of bronze mirrors were made in different historical periods,particularly in the Warring States Period,the Han and Tang Dynasties,which were the three peaks of the development of bronze mirror arts in ancient China.The casting techniques were exquisite.The surface of the bronze mirror was smooth and bright enough to reflect one's image,and there were scarcely any casting defects on the mirror surface.On the back of the bronze mirror,there were rich depictions of Arts and Humanities,and the ornamentations were also     

The 9th China International Diecasting Congress & Exhibition

The 9th China International Diecasting Congress ＆ Exhibition was held on July 22-24, 2014 at Shanghai New International Expc Centre. This exhibition was the most successful over the years, with over 6890 visitors and 155 exhibitors, and the exhibition area increased by 30% from 9,500 square meters in 2012 to 12340 square meters. Die casting enterprises from a total of 24 countries and regions, including China mainland, Chinese Taiwan and Hong Kong, South Korea, Japan, Germany, India, Thailand, Malaysia, the United States, Russia, Australia, Iran, Ukraine, Brazil, Colombia, Singapore, Austria, Canada, Croatia, France, Turkey, United Kingdom, Vietnam, attended the congress and exhibition.     

Introduction of the Fluid Control Engineering Institute of Kunming University of Science and Technology

正The Fluid Control Engineering Institute of Kunming University of Science and Technology was set up in 1996.The researches of institute concentrate on electro-hydraulic(pneumatic)servo/proportional control and hydromechatronics.The Institute is committed to research and development of electro-hydraulic control of high-end technical equipment in ferrous metallurgy refining produc-     

RARE METALS Volume Contents

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