基于分路分量冷却的主轴热偏移控制方法研究

为有效控制主轴的热偏移现象,对数控卧式铣镗床主轴系统进行了热特性分析,提出一种分路分量冷却的主轴热偏移控制方法。设计不同流量的冷却油路,保证主轴轴承的热量被有效带走,进而控制主轴的热伸长,并在样机上进行了试验验证,确定了该方法的有效性。     

精密直联式主轴系统的结构设计

对不同类型的主轴系统进行分析对比,确定直联式主轴为高精度数控卧式坐标镗床的主轴系统类型;从机床实际的加工工艺需求出发,计算得到不同加工方式下的最大切削力学参数,以此为基础完成主电机与主轴轴承的选型计算;根据主轴系统的功能与精度要求进行结构设计,从而完成精密直联式主轴的完整设计。样机的试制与应用验证表明,该直联式主轴的精度与性能水平达到设计要求。     

用矿石代废钢熔炼优质铸铁

我厂自一九七一年三月在厂党委的关怀和领导下,开始试验用赤铁矿石代替(部分代替)废钢熔炼优质铸铁,并于同年七月全面投入生产使用,通过几年来的生产实践,经摸索和改进,使熔炼操作逐渐正常、稳定,并浇注了座标镗床、卧式镗床、电动仿型铣、万能工具铣等机床铸铁件,重量从100公斤到4吨左右,共生产了二万多吨铸件。熔炼的铸铁性能比较稳定,达到设计要求,铸件质量良好。     

风冷散热装置在机床主传动系统中的应用

提出一种全新的机床主传动冷却方式,特别适用于卧式铣镗床。采用小型液压泵站,结合风冷散热装置对机床主传动系统进行循环冷却。经过严格设计与计算,选择适合的冷却装置,合理安排主传动系统冷却装置的布局,在机床要求的环境温度下,满足主传动系统散热要求,使设备能够连续稳定运行。该冷却方式结构紧凑、清洁环保,提高了换热效率、使用寿命及主轴的切削精度。     

齐齐哈尔二机床广泛开展国际合作

<正>为了进一步缩小与国际先进技术水平的差距,齐二机床广泛开展国际合作。近几年,企业与德国罗特乐公司就高档重型数控落地铣镗床、与意大利FMT公司就大型数控导轨磨床、与瑞典APT公司就重型数控油压机、与美国环球公司就精密数控卧式铣镗床进行技术合作。特别是与德国哈格自动化公司合作开发的     

落地铣镗床主轴系统优化研究

建立了落地铣镗床主轴系统的模型,研究主轴径向变形;对落地铣镗床主轴轴承寿命、主轴大齿轮对轴承刚度和主轴变形的影响进行分析,并对轴承配置进行了优化分析,为轴承组合方式的选用以及大齿轮支承的合理配置提供了依据。     

基于模糊故障树的某重型数控机床主轴系统可靠性分析

为提高数控机床主轴系统的可靠性,找出主轴系统的薄弱环节,以某重型数控卧式铣镗床主轴系统为研究对象,建立以主轴系统故障为顶事件的故障树。由于时间和成本的限制很难得到基本事件故障率的准确值,因此结合专家判断法和模糊集理论,将专家意见汇总为梯形模糊数,确定出基本事件的发生概率,对故障树展开定性定量分析,并计算基本事件的重要度。最后通过基本事件的重要度排序结果,确定出影响系统的关键故障因素。     

西门子Simotion运动控制器在普通卧式镗床中的应用

本文介绍了西门子Simotion运动控制器在普通卧式镗床中的应用。在不改变镗床主要机械结构前提下,主轴使用变频控制器取代了传统的机械齿轮调速,进给轴利用闭环的伺服驱动技术,实现点到点精确定位,多种自动加工循环功能。通过应用先进的运动控制技术,将普通镗床改造成一款高精度,低消耗的半自动加工机床。     

重心驱动原理在高速卧式镗铣加工中心关键部件结构设计中的应用

介绍了重心驱动技术的原理,针对高速卧式镗铣加工中心的结构特点,提出了将重心驱动技术应用在主轴箱、滑架等关键部件结构设计的方法.利用有限元分析软件对应用“重心驱动技术的高速卧式镗铣加工中心整机进行了动静态特性分析,得到了其应力、应变图及前四阶固有频率和振型图.分析结果表明采用“重心驱动”的加工中心具有良好的动静态特性,因此重心驱动技术作为一种新型的数控机床进给驱动方式,可以有效地减少加工中心的振动,提高其动静态特性.     

TM738新型镗床

湖南长沙轴瓦设备厂研制成功一种功能齐全、结构新颖的TM738型卧式精密轴瓦镗床，并已通过了省级鉴定。其中螳头倾斜双刀镗削等五项设计已获国家专利。价格大大低于进口同类机床。该镗床主轴系统采用先进的动静压轴承；动作功能采用PCL控制，健头倾斜双刀螳削加工解决了我国长期瓦口削薄尺寸和不等原瓦加工达不到要求的难题。TM738新型镗床@胡正隆     

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。     

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.     

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.     

Effect of Short-Time Aging on the Pitting Corrosion Behavior of a Novel Lean Duplex Stainless Steel 2002

The effect of short-time aging in the temperature range between 400 and 1000 °C on the pitting corrosion behavior and mechanical property of a novel lean duplex stainless steel(LDSS) 2002 was investigated through the potentiostatic critical pitting temperature(CPT) tests and the Charpy impact tests. Both the pitting corrosion resistance and the toughness of aged specimens degraded due to the precipitation of detrimental secondary phases and the most significant reduction of CPT and impact energy emerged at 650 °C concurrently. The CPT of LDSS 2002 specimen aged at 650 °C decreased by 28 °C, and the impact energy dropped from 69 to 29 J/cm~2 compared with the solution-annealed sample. Transmission electron microscopy characterization showed that the main precipitates in LDSS 2002 were Cr_2N and M_(23)C_6 along the ferrite–austenite grain boundaries.     

Information for Contributors

正The Transactions of Nonferrous Metals Society of China,founded in 1991 and sponsored by The Nonferrous Metals Society of China,is published monthly now and mainly contains reports of original research which reflect the new progresses in the field of nonferrous metals science and technology,including mineral processing,extraction metallurgy,metallic materials and heat treatments,metal working,physical metallurgy,powder metallurgy,with the emphasis     

Preface

<正>We are pleased to present this Special Issue of Transactions of Nonferrous Metals Society of China containing selected papers from the First Asian Conference on Aluminum Alloys(ACAA-2013),held in Beijing,China,13–17 October 2013.This conference has been initiated,with approval of     

Information for Contributors

The Transactions of Nonferrous Metals Society of China, founded in 1991 and sponsored by The Nonferrous Metals Society of China, is published monthly now and mainly contains reports of original research which reflect the new progresses in the field of nonferrous metals science and technology, including mineral processing, extraction metallurgy, metallic materials and heat treatments, metal working, physical metallurgy, powder metallurgy, with the emphasis on fundamental science. It is the unique preeminent publication in English for scientists, engineers, under/post-graduates on the field of nonferrous metals industry. This journal is covered by many famous abstract/index systems and databases such as SCI Expanded, Ei Compendex Plus, 1NSPEC, CA, METADEX, AJ and JICST.