第九届中国国际模具技术和设备展览会模具水平评述

对第九届中国国际模具技术和设备展览会上展出的各类模具，模具标准件及模具材料进行了评述，介绍了主要展品的技术特点，分析了我国模具制造水平与国外先进水平的差距，展望了模具技术的发展趋势。     

应用SparkDepo系统进行模具维护的技术

在生产过程中，模具往往由于各种原因而造成磨损和一定程度的损伤，本文介绍了用ＳｐａｒｋＤｅｐｏ系统对模具进行修复和维护的技术，简要介绍了ＳｐａｒｋＤｅｐｏ系统的结构，工作原理，分析了其优缺点，并与其他的修复和维修技术进行了对照，结果表明，该系统是一种实用的效的系统。     

模具制造业如何满足市场需求

用比别人更快的速度向市场提供所需的高质量产品在80年代曾支配了英国工业，并为社会性的革命铺平道路。PhilCapes认为，模具制造业更符合这一情况。在英国，分承包工具制造业一直是很兴旺的，而因公司合理化而导致取消大量公司内设工具室，更将此行业推上了急剧增长之路。在80年代和90年代初，就已经看出在专有的设计和加工设备开发中的实际进步。在一个非常现代化的分承包的模具制造厂中，从CAD／CAM开始，一直到计算机数控、线切割、高速切削及工具制造商采用的快速样机技术是极其先进的。需要要求供应商解决商业环境中的许多问题以…     

导轨模具的改进

我厂生产的按钮产品中，有一塑料零件导轨（图1），在原生产导轨的模具中采用了如图2所示的推杆型式，工作原理为：开模时，动模板8定模板10分开，斜导柱5抽开左右滑块16，动模8继续下行，注射机项动推板24，塑料件被推杆19顶出．合模时，弹簧21和复位杆20使推杆19复位．模具制造技方便，但在注射连续生产中，合模时常发生推杆复位不及时（主要靠弹簧复位），造成推杆与滑块相擦损坏模具，耽误了零件加工而影响正常生产。因此，我厂模具车间钳工师傅开动脑筋，将导轨注射模结构改成图3所示的型式，在模板10下面加一块推件极7，开模时动模板1…     

废旧模具钢5CrMnMo铸造回用

采用铸造方法，将废旧模具重熔，在铸造过程中严格控制C、Mn,Si及合金元素含量，采用高温出炉进行变质处理，低温浇注，使用易割冒口，生产的铸造模具，在使用寿命上与锻造模具基本一致。     

温挤压模具的早期失效探讨及对策

针对温挤压模具在高温高压下产生早期失效的现象，探讨和剖析了模具早期失效产生的因素，从模具设计、模具材料、模具冷却和模具润滑等方面提出了对策。     

模具标准件的发展趋势及需要解决的问题

通过对模具产业特征的描述，阐述了模具标准件的作用，分析了我国模具行业及模具标准件市场的现状，提出了加速模具标准件发展需解决的问题。     

模具制造技术与发展趋势

论述了模具与模具工业概况，以及我国模具工业的现状和发展趋势，指出了我国模具技术与国外的差距，同时对国内外的模具市场进行了分析。     

关于提高铝合金压铸模具寿命的探讨与研究

铝合金压铸在生产中，模具寿命是关键。从模具结构、模具制造工艺、以及压铸工艺等三个方面，比较严密地论述了如何提高模具寿命的问题，重点介绍了分体式镶块结构，分析了有关模具设计的计算、以及模具制造、使用中的注意事项。提到的使用热超导管冷却模具是一项全新技术，很有发展前景。     

模具材料及热处理技术对模具寿命影响的研究

模具热处理不当及模具材料选择不合格，是造成模具早期失效的重要原因。模具寿命是衡量模具技术水平的重要标志，直接关系到加工生产的效率、质量和成本。影响模具寿命的因素很多，本文着重分析并总结了模具材料选择和热处理技术方面的影响因素，对模具的设计和制造，具有重要参考价值和推广意义。     

院校研究的基本范式:定性模式与定量模式

院校研究有两种研究路向,一种是“(问题)一理论—假设—观察一理论一(问题)”的研究路径,另一种是“(问题)一观察一概括一理论—观察一(问题)”的研究路径。从哲学方法论层面看,院校研究主要有四种研究范式,即经验主义、实证主义、结构主义和人本主义。其中,实证主义和经验主义是定量研究的方法论基础,结构主义与人本主义是定性研究的方法论基础。定性研究与定量研究并不是绝对的两分,它们构成一个连续的系谱。实验法与文学法位于这一系谱的两个极端。     

“我国古代大型铸铜文物”系列文章之十三：古代大铜锅和大铜缸（待续）

叙述了古代大铜锅和大铜缸的有关情况。在现存的26口古代大铜锅中,重点介绍了其中6口大铜锅的尺寸、铸造年代、功用、特点和存放地。而现存的165口古代大铜缸,都是明、清两代铸造的,绝大多数都存于北京故宫,本文较详细地介绍了其中5口大铜缸的有关情况。     

Rupture locations of friction stir welded joints of AA2017-T351 and AA6061-T6 aluminum alloys

The tensile rupture locations of friction stir welded joints of AA2017-T351 and AA6061-T6 aluminum alloys were examined. The experiments show that the rupture locations of the joints are different for the two aluminum alloys, which are influenced by the welding parameters. When the joints are free of welding defects, the AA2017-T351 joints are ruptured in the weld nugget adjacent to the thermo-mechanically affected zone on the advancing side and the rupture surfaces appear as oval contours of the weld nugget, while the AA6061-T6 joints are ruptured in the heat affected zone on the retreating side and the rupture surfaces are inclined at a certain degree to the bottom surfaces of the joints. When welding defects are present in the joints, the AA2017-T351 joints are ruptured in the weld center, while the AA6061-T6 joints are ruptured on the retreating side near the weld center. The rupture locations of the joints are dependent on the internal structures of the joints and can be explained through them.     

An ab initio study of Ti-Y-O nanocluster energetics in nanostructured ferritic alloys

So-called oxide dispersion strengthened steels or nanostructured ferritic alloys (NFAs) contain nanoprecipitates which give them exceptional mechanical properties and resistance to radiation effects. However, the structure and composition of these nanoprecipitates are still uncertain. To help clarify the nature of the smallest nanoprecipitates, density functional theory calculations are used to investigate the most stable Ti, Y, and O nanocluster computational units in Fe. Two distinct methods for searching for stable nanoclusters are proposed: one in which nanoclusters are restricted to the body-centered cubic Fe lattice and one in which the nanocluster structures are strained variants of bulk Ti and Y oxides. We discovered that nanoclusters that are structurally similar to bulk Ti and Y oxides are significantly more stable than nanoclusters that are restricted to the Fe lattice. Consequently, the most stable nanoprecipitates in Ti-Y-O NFAs are more likely to be small oxide phases than coherent solute-enriched clusters.     

2219铝合金不同气氛下TIG焊焊接接头组织性能

为研究氦弧TIG焊焊缝质量,对比分析了2219铝合金氦弧TIG焊与氩弧TIG焊焊缝成形及组织性能.结果表明,在背部熔宽相同的条件下,氦弧TIG焊焊缝正面熔宽、下塌量及热影响区宽度均小于氩弧TIG焊,氦弧TIG焊与氩弧TIG焊焊缝的微观组织及第二相组织基本相似,焊缝区晶粒为等轴晶,热影响区晶粒为粗大的板条状,组织为粗大的α铝基体与金属间化合物Al₂Cu及少量的共晶组织,焊缝区的第二相组织明显多于热影响区,无法发挥弥散强化的作用.氦弧TIG焊与氩弧TIG焊焊接接头的断裂方式均为韧性断裂,抗拉强度基本保持一致,氦弧TIG焊焊接接头的断裂总延伸率高于氩弧TIG焊,维氏硬度高于氩弧TIG焊焊缝的硬度.     

机械合金化的反应机制研究进展

介绍了机械合金化技术的基本原理、工艺过程及特点，对目前机械合金化存在的两种机制进行了分析，指出通过原子扩散逐渐实现合金化反应机制和爆炸式反应机制实质上是相似的，导致效果的不同主要在于合金体系的形成热不同。另外对影响机械合金化过程的因素以及该工艺存在的缺陷进行了阐述。     

GMAW焊接熔滴过渡动态过程的数值分析

以流体动力学、电磁理论及VOF方法为基础建立了熔滴过渡的动态模拟模型，模型中考虑电磁收缩力、表面张力、等离子流力的影响．利用建立的模型模拟了熔滴的形成、长大及脱离过程，计算了电流对过渡熔滴尺寸及频率的影响，计算结果与实验结果吻合较好．计算了不同阶段的熔滴中的流场，并利用计算的流场分析了熔滴的脱离机制。     

Characterization of nanostructured TiN coatings fabricated by reactive plasma spraying

The nanostructured TiN coatings are fabricated by means of reactive plasma spraying micrometers titanium powders in the atmosphere, and the microstructure and performance of the coatings are analyzed by XRD, SEM and TEM. The experimental results show that the coatings are mainly composed of TiN and Ti₃O phases, and the coatings have the typical sprayed lamellae structures. In parallel to substrate surface direction, the nanoscale grains with particle diameters ranging from 60 to 120nm are observed in the coatings, and both fine equiaxed and columnar grains are found in some zones of the nanostructured TiN coatings. But in vertical to substrate surface direction, the contrary is the case. Thus it can be concluded that the TiN coatings are composed of the columnar grains, and the columnar grains are nanostructural equiaxed grains in their cross-section. In addition, a large number of deformation twins caused by the stresses concentration are found in TiN coatings. Meanwhile, the nanostructured TiN coatings have a higher bonding strength and better fracture toughness than other observed as-sprayed coatings.     

自动TIG堆焊熔敷铜熔池图像视觉检测试验

提出了近红外波段取像的思路，设计了基于不同取像机理的两种复合窄带滤光系统，在脉冲TIG焊的电弧加热下，采用普通CCD传感器从正面对重熔自动TIG堆焊铜熔池进行了传感采集，对1064nm、980nm、520nm和405nm滤光条件下的取像结果进行了比较分析，找到了相对较好的取像窗口，获得了清晰的铜熔池图像。由传感试验结果得出，采用TIG弧热源，近红外波段易于获得较清晰的熔池图像；脉冲TIG弧基值期间利用四种滤光波段都可获得清晰的熔池图像。并对重熔自动TIG堆焊铜熔池的特征和熔深的控制进行了分析和试验研究。     

An investigation on the elastic modulus and density of vacuum casted aluminum alloy 2024 containing lithium additions

The elastic modulus and density of (2024+LiX) alloys are investigated. To the alloy of 2024, the weight percentages of lithium added are 2,3, and 4. Melting is carried out in an induction furnace under argon gas protection; casting is done under vacuum. To obtain the maximum strength and hardness, the specimens are solution heat treated under 495 C and quenched in water at room temperature. Then, they are aged naturally and artificially. For the purposes of comparing, some of the specimens are melted under argon gas, but casting is done without vacuum. All the specimens are subjected to tension tests. As a result of this work, the alloys of aluminum that are difficult to manufacture by the known methods are manufactured safely by the vacuum casting method. For 1% of lithium added to the alloy, an increase of 6% in the elastic modulus and 3% decrease in the density are obtained. The specific elastic modulus, E/ρ, ratio increases by about 10% for each 1% addition of lithium.