材料学院毕业设计摘要.doc

材料成型及控制工程*铜钢异种金属机器人等离子焊接技术研究（良）摘要：该课题针对铜钢异种金属焊接，利用弧焊机器人系统，结合等离子焊接方法，实现钢基本上堆焊铜的等离子焊接工艺（Introduction）。运用机器人示教编程器对焊接工艺进行示教程序编制，完成了单层焊和双层焊工艺的示教程序编制，控制机器人等离子焊机进行自动焊接试验（Materials and Methods）。通过对比不同工艺参数下进行焊接试验得到的焊接接头质量，确定了焊接电流，焊接速度，工装轴转速，送丝速度，喷嘴距工件的距离等合理的工艺参数（Results）。对焊接后的试样进行微观组织分析，接头无气孔、未焊合、夹渣等焊接缺陷。关键词：铜钢异种金属，机器人，等离子弧焊Research robot plasma arc welding technology of copper steel dissimilar metalsAbstract: The top is about the joint between copper steel dissimilar metals. Using robot plasma arc welding system, combined with the methods of plasma arc welding to achieve the welding process of depositing a layer of copper based on the steel matrix. Completing the single welding and double layers welding process with using a robot teaching-programming pendant, to control the plasma welding robot for automatic welding test. by comparing the welded joints from the text with different process parameters, developed reasonable parameters of welding current, welding speed, wire feed speed, the distance between the nozzle from the workpiece, and so on. Through the microstructure analysis testing, there are no pores, soldering, folder jardine and the Pan-iron welding defect in the welding joint.Key words: copper steel dissimilar metals, robot, plasma arc weldingGMAW焊机数字化控制设计（良）摘要：针对传统模拟控制GMAW逆变焊机的数字化控制问题，深入分析了原NBC-500逆变焊机的控制电路，设计逆变焊机数字控制方案；同时分析了motoman NX100机器人控制器的弧焊接口，应用Protel电路设计软件，基于线性光耦的线性变换原理，设计了逆变焊机与机器人的数字化控制接口，对所采用元器件进行了数据采集分析处理，对焊机电源主控制电路板进行了观察分析以及信号确认，连接了接口电路印刷电路板与焊机电源主控制电路，实现了焊机参数的机器人调节与控制，初步实现了NBC-500型逆变焊机的数字化控制。关键词：GMAW，焊机，接口电路，元器件Design of digital control for GMAW welding machineAbstract: In accordance with the GMAW traditional control of digital inverter welding machine control, depth analysis of the orginal NBC-500 of the control circuit of inverter welding machine, inverter welding machine design of digital control programs; at the same time, analyze the MOTOMAN NX100 of the arc welding robot controller, application Protel circuir design software, based on the linear transformation of linear optocoupler theory, the design of the inverter welding machine and robotic digital control interface, the components were used in data acquisition and analysis processing, the main control circuit board, and to observe and analyze the signal confirmed that the interfance circuit to connect the printed circuit board with the main control circuit of welding power. Welding parameters achieve the regulation and control of robots, the initial realization of the NBC-500 inverter welding machine digital control.Key words: GMAW, welding machine, interface circuit, componentAl2O3陶瓷表面化学镀Ni-P工艺及其连接技术（良）摘要：本文以改善陶瓷的焊接性为目的，以Al2O3陶瓷表面化学镀镍技术为核心内容，主要研究了氧化铝陶瓷表面前处理工艺各个工序，制订了前处理流程为化学镀镍前准备除油表面粗化表面敏化表面活化还原；研究得到化学镀镍磷的优化工艺为硫酸镍浓度15g/L，次亚磷酸钠25g/L，丙酸钠13g/L，pH值4.5-5.5，温度35-400C，时间根据镀层厚度需要而定。对镀镍磷Al2O3陶瓷在真空炉中热处理后进行了低温钎焊工艺试验，研究了镀镍磷Al2O3陶瓷的焊接性，讨论了不同的钎焊温度和钎焊时间对接头组织及力学的影响。结果表明，钎焊温度越高，焊缝缺陷增加，焊缝质量越差；而焊接时间增加，焊缝组织更紧密，分布更均匀，焊接质量也较好；最佳的焊接工艺为：温度3500C，焊接时间根据需要来确定，最短不能低于10min。关键词：Al2O3陶瓷，化学镀，真空热处理，低温钎焊Al2O3 ceramic surface Ni-P electroless plating process and its connectingAbstract: In this article, we make it that in order to improve the welding of ceramics as the purpose, and electroless nickel plating technology on the Al2O3 ceramic surface as the core, and we studied various processes of alumina ceramic surface pre-treatment process, developed a pre-treatment of electroless nickel plating process such as the preparation of chemical nickel plating, oil removal, suface coarsening , surface of sensitizedl, surface activation, reduction, the optimization result of electroless Ni-P plating is that nickel sulfate concentration of 15g/L, sodium hypophosphite 25g/L, sodium 13g/L, pH value of 4.5-5.5, temperature 35-400C, the time according to the needs of the coating thickness. Put the Al2O3 ceramic-plated nickel-phosphorus in a vacuum furnace for the heat treatment and then brazing process of the low-temperature experiment was conducted in order to study Ni-P welding of Al2O3 ceramic, to discuss the impact of different brazing temperature and time on the mechanical performance of the joints. Results showed that , the higher the temperature brazing, weld defects increase, the worse the quality of welds, and welding time, welding closer, more uniform distribution, better welding quality. So the best welding procedure is that temperature 3500C, the time according to the needs, the minimum duration is 10 min.Key words: Al2O3 ceramic, electroless plating, vacuum heat treatment, soldering in low temperature超高强板螺柱焊工艺与热影响区性能实验研究（良）摘要：针对高强高硬合金钢与大直径实心螺柱焊接，采用感应加热+螺柱电弧复合热源进行焊接试验研究，探索出最佳的焊接工艺方法。结果表明，对于厚度分别为45mm、80mm装甲钢与直径27mm实心螺柱，再合适的工艺参数下，焊接过程稳定，外观成形美观，有效的避免了末熔合，成形不良等焊接缺陷，抗剪强度达到380Mpa以上。接头显微组织观察表明，螺柱和高强高硬合金钢母材加热、熔化均均匀，组织界面过渡自然，未发现末熔合，成型不良等缺陷，焊接接头力学性能良好。针对高强超高强钢大直径实心螺柱在有大拘束的条件下进行复合热源焊接，对焊接接头产生的冷裂纹为进行研究，并结合实际情况，指出如何在焊接过程中控制并减少焊接冷冽纹的出现。关键词：高强高硬合金钢，大直径实心螺柱，复合热源，冷裂纹Ultra-high strength plates stud welding process and heat-affected zone experimental study on performanceAbstract: High-strength alloy steel for high hard stud with large-diameter solid welding, the use of induction heating stud arc welding heat composite pilot study to explore the best methods of welding technology. The results showed that the thickness of 45mm, 80mm armored solid steel stud and 27mm in diameter, in the appropriate process parameters, the welding process stability, forming the appearance of beautiful, is not effective to avoid a fusion, forming undesirable defects, such as welding, shear strength reached more than 380 Mpa. Joint microstructure observation showed that the stud and hardware high-strength and high-alloy steel base metal heating, melting both the uniform interface of natural transition, was found not fusion, forming defects such as bad, good mechanical properties of weilded joints.Ultra-high strength steel for high strength large diameter stud binding in a large complex under conditions of heat welding, welded joint on the cold produced by crack for the purpose of research, combined with the actual situation, pointing out that how to control the welding process and to reduce cold welding crack emergence.Key words: high-strength alloy steel hardware, stud welding large-diameter solid welded joints, composite heat, cold crack大型钢结构失效分析 （优）摘要：本文通过对ANSYS软件模拟、小孔应力释放试验对大型钢结构失效进行分析。在模拟时采用二维模型，通过在建模、求解加载时设置不同的变量值，模拟出不同焊接情况下的应力场分布；在小孔应力释放试验时，通过在焊接上钻盲孔，用应变仪器量钻孔后焊缝的应变释放量，通过实验公式换算为应力，发现焊缝残余应力接近甚至高于材料的屈服强度。通过对模拟和试验结果进行对比分析，得出焊接钢结构失效的主要原因是结构设计不合理，即在钢柱腹板上焊接时，影响应力分布的主要原因是焊缝端部到翼缘之间的距离，该距离存在一个临界最小值使得钢结构不因结构不合理而失效。关键词：钢结构，失效，模拟，应力释放The analysis of the Large-scale steel structure expirationAbstract: This article through the ANSYS software simulation, and the eyelet stress release experiments to analysis the large-scale steel structure expiration. When simulation was carried out the two-dimensional model was used. For simulating in the different welding situation, the modeling, the solution and the loads establishes should be defined in the different variable value. During stress release experiment, the strain gauge measurement was used to measure the strain release quantity, when drilling the blind hole on the welded joint. Through the empirical formula conversion, discovered the welded joint stress is close or even higher than the yield strength of the material. Through the simulation and the test result, the primary cause of the welded steel structure expires is that the structural design is unreasonable.Key words: steel structure, expiration, simulation, stress release弧焊机器人焊接工艺推理设计技术研究 (及格)本课题针对弧焊机器人焊接工艺，研究弧焊机器人焊接工艺推理设计研究技术。在分析弧焊机器人焊接工艺推理设计过程的基础上初步建立弧焊机器人WCAPP系统框架。设计了WCAPP焊接工艺智能设计系统的体系结构，分析了弧焊机器人焊接焊接工艺推理规则，完成了WCAPP软件总框架设计，采用了SSTab等控件等技术设计了登陆界面、总体界面、接头信息管理和维护界面、焊接工艺实验报告管理和维护界面以及智能化推理工艺卡界面。并对弧焊机器人WCAPP软件功能和焊接数据库进行需求分析。关键词：焊接工艺推理，WCAPP系统，模块设计Arc welding robot welding technology research designAbstract: The top for the arc welding robot welding technology to study the arc-welding robot welding technology design reasoning. The anaysis of arc welding robot welding technology design process of reasoning based on the initial establishment of the framework of arc welding robot system WCAPP. Designed WCAPP welding technology of intelligent design system architecture, analysis of the arc welding robot welding technology reasoning rules, the completion of the overall framework of WCAPP software design, use of technologies such as SSTab control design, such as the landing interface, general interface, information management connector and maintenance interface, the experimental report of welding technology to manage and maintain the interface as well as the reasoning process of intelligent interface card. And arc-welding robot and welding WCAPP software needs analysis database.Key words: welding process reasoning, WCAPP system, modular design材料科学与工程nano-HA/PVA复合水凝胶软骨修复材料的制备及生物相容性研究（良）用原位复合加冷冻解冻法制备nano-HA/PVA复合水凝胶，研究了nano-HA/PVA复合水凝胶的生物相容性，并与PVA水凝胶做比较。用X射线衍射分析（XRD）、透射电镜（TEM）、扫描电镜（SEM）等方法对聚乙烯醇/纳米羟基磷灰石复合水凝胶的晶态结构及分散状态进行了表征，分别对nano-HA/PVA复合水凝胶和PVA水凝胶进行含水量测试，溶血试验和MTT实验，结果表明，聚乙烯醇/纳米羟基磷灰石复合水凝胶形成了良好的结晶结构且分散良好，分布均匀。PVA+低HA复合水凝胶和PVA水凝胶的溶血率分别为1.8%和1.89%，MTT实验中的吸光度分别为0.9320.045 和0.9030.028。结果表明，nano-HA/PVA复合水凝胶和PVA水凝胶都有着良好的生物相容性。关键词：聚乙烯醇，羟基磷灰石，复合水凝胶，原位复位，冷冻解冻，生物相容性，溶血试验，MTT实验Preparation of Polyvinyl Alcohol / nano-Hydroxyapatite Composite Hydrogel and Its biocompatibilityAbstract: A new kind of bioactive polyvinyl alcohol (PVA) / nano-Hydroxyapatite (HAP) blend hydrogels were prepared by in situ synthesis method combined with freexing-thawing method. Biocompatibility of nano-HA/PVA blend hydrogels compared with PVA hydrogel was investigated. The crystal structure and dispersed statement of nano HA/PVA blend hydrogels were characterized by XRD, TEM and SEM. Nano-HA/PVA blend hydrogels and PVA hydrogel were tested by use of Water content, hemolysis test and MTT method. Ultrafine granular crystalline was formed in blend hydrogels, which was well dispersed. The results showed that the hemolysis rate of PVA + lowGA blend hydrogels is 1.83%, the hemolysis rate of PVA hydrogel is 1.89%. The absorbance of PVA + lowHA blend hydrogels is 0.9320.045 and the absorbance of PVA hydrogel is 0.9030.028. Results demonstrated that both of them have good biocompatibility.Key wrods: PVA, HAP, blend hydrogels, in situ synthesis method, blend hydrogels, biocompatibility, hemolysis test, MTT Water content*感应烧结工艺对铁基粉末冶金材料组织与性能的影响（良）本文以铁粉和碳粉为原料，通过压制成型-感应加热烧结的工艺路线制备样品（Introduction）。所制样品的含碳量分别为0%， 0.4%，0.8%，并且每种成分的样品还分为三种密度，利用感应加热对样品在不同温度下进行烧结，烧结温度分别为11600C，12000C，12400C (Materials and Methods)。通过金相观察和硬度测试来分析不同感应烧结温度、不同成分及密度对铁基粉末冶金材料组织和性能的影响。结果表明：随着密度的增加，粉末冶金材料的孔隙度会逐渐降低，硬度值逐渐升高（Results）。材料组织中的珠光体含量会随着碳含量的增加而增大，试样的硬度也随之增大。随着感应烧结温度的升高，孔隙度会逐渐降低，但是在温度升高到一定值时，孔隙含量的变化并不明显。对于含碳的试样，随着感应烧结温度的升高，微观组织中的珠光体含量增大，但材料的硬度并不是随着烧结温度的改变呈线性变化的，而是先减小后增大，在12000C烧结时的硬度值最小(Discussion)。关键词：铁基粉末冶金，感应加热，孔隙，性能Induction sintering impact on the organization and performance of Fe-based powder metallurgy materialAbstract: In this dissertation, iron power and carbon power was used as raw material. Samples were prepared from the forming process of suppression to induction heating sintering. The carbon content of the sample system was 0%, 0.4% and 0.8%, and each element of the sample was divided into three types by the dentsity. Samples were sintered at different sintering temperature by induction heating and the sintering temperature is 11600C，12000C and 12400C. The effect of the different sintering temperature, different components and density to the organization and performance of the Fe-based powder metallurgy materials was analyzed by metallographic observation and hardness test. the results showed that: with the increase in density, porosity of powder metallurgy materials will be gradually reduced, the hardness value increased gradually. The content of pearlite will increase with the content of carbon, the hardness of the sample also increases. With the temperature increasing, the porosity will be gradually reduced, but to a certain temperature value, the porosity does not significantly change. For the sample content carbon, with the temperature increasing, the microstructure of the pearlite content increases. However, the hardness of the material does not change with the sintering temperature change is linear, 12000C sintering in the hardness of the minimum value.Key words: Fe-based powder metallurgy, induction heating, hole, property具有生物结构神态材料的制备及微观结构研究 (中)由于木材组织结构方面的独特性，制备多级孔结构的木材生态陶瓷在探索特殊微观结构和性能之间的关系方面有着重大的意义。本文以蚕丝为生物模版成功制备了具有蚕丝微观结构的Al2O3和Fe2O3遗态陶瓷，同时分析研究了烧结温度、浸渍溶液浓度和浸渍时间等工艺参数对遗态材料的组织和结构的影响规律。结果表明，烧结温度影响氧化物相形成与相变，浸渍溶液浓度影响陶瓷纤维表面形貌，浸渍时间影响陶瓷纤维厚度。关键词：蚕丝模版，Al2O3和Fe2O3生态陶瓷，烧结温度，浸渍时间，浸渍溶液浓度Preparation and microstructure study of Eco-materials with biological structuresAbstract: Because of the unique structure of Timber Organization, preparation of multi-level pore structure of wood has great significance in exploring the special relationship between eco-ceramic microstructure and properties. In this paper, preparation Al2O3 and Fe2O3 ecology ceramic of silk microstructure with the silk as biological template. At the same time, researching the Process Parameters such as the sintering temperature, soaking time and concentration of impregnating solution left state of the organization and structure of materials analyzed. The results showed that, the sintering temperature affected Oxice phase formation and phase transition, Impregnating solution concentration affected the surface morphology of ceramic fiber, ceramic fiber impregnation affected the thickness of time.Key words: Al2O3 and Fe2O3, ecology ceramic, silk template, the sintering temperature, soaking time, concentration of solutionAZ31镁合金塑性变形中的孪生行为 （优）镁合金中，孪生是一种重要的晶内塑性变形机制。本文探讨了镁合金塑性变形中的孪生机制以及孪生的影响因素。将挤压态AZ31镁合金进行退火处理，得到不同晶粒尺寸的试样，然后采用不同加载方法进行力学试验，并且对纤维组织图片以及TEM图片进行分析。确定了结构和晶粒尺寸是影响孪生的两个主要因素，以及孪生在不同加载方向下拉伸或压缩变形时孪生发生率的显著不同导致了积压屈服不对称性。由于结构的组织，以不同的方向和方式加载时，孪生的开动情况也不一样。关键词：镁合金，塑性变形，孪生，孪晶AZ31 magnesium alloy in the plastic deformation behavior of the twinAbstract: In Magnesium alloy, the twin is an important plastic deformation mechanism in crystal. This paper discusses the plastic deformation of magnesium alloy twin mechanisms, as well as the impact of the twin factors. In order to obtain AZ31 magnesium alloys with different grain size, the samples are annealed at 4200C for different time, then carried out mechanical tests by different load direction and load manner, and analyse the picture of the microstructure as well as the TEM image. To determine the texture and grain size is the twin effects of the two main factors, as well as the twins in different directions under tensile load or compressive deformation occurred when the twins are significant differences between rates has led to tension and compression yield asymmetry. Because of the role of texture, different directions and means to load, the twin is not the same operation.Key words: electron alloys, plastic yield, twinning, twin背压ECAP中镁合金的组织演变(优)摘要：作为最轻的金属结构材料，镁合金有着广泛的应用前景，但其室温塑性差、强度低等缺点又制约了它的应用。为了克服这个难题，特别是在提高AZ31镁合金塑性变形能力的同时获得较高的屈服强度，本文对2000C下一道次ECAP变形和一道次BP-ECAP变形后的AZ31镁合金分别进行了微观组织、力学性能和结构演变的测定。进行室温下的拉伸力学试验，研究AZ31镁合金的力学性能；同时通过金相显微分析、透射电子显微分析来研究微观组织的变化；通过极图和取向分布函数（ODF）分析在变形过程中结构的演变。研究结果表明：一道次BP-ECAP以后，晶粒明显细化的同时材料塑性和屈服强度都得到了大幅提升；BP方式所得（0002）极图与ECAP相比出现了新的极点：TEM照片显示了样品中c+a位错的存在，并且证实了在ECAP中引入背压能够使c+a非基面滑移系开动；计算机模拟应力应变曲线与实测结果基本一致，证明了模型的正确性；而BP方式下c+a非基面滑移开动份额大幅提升，进一步证明了背压的加入能够使得c+a非基面滑动激活。关键词：AZ31镁合金，背压，等径角挤压（ECAP），c+a非基面滑移Analysis on evolution of microstructure and texture of magnesium alloys during equal channel angular pressing with backpressureAbstract: As the lightest metallic structural material, magnesium alloys are attractive for many applications. However, the applications of magnesium alloys have been limited due to the poor plasticity and low strength at room temperature. In order to overcome this serious obstacle, especially to improve the dictility and strength of AZ31 alloys at same time. In this paper, microstructure, mechanical property and texture development of an AZ31 Mg alloy during one pass equal channel angular pressing (ECAP) with and without backpressure at 2000C were investigated. The mechanical properties were tested by tensile testing at room temperature, and microstructures have been investigated using optical microscopy (OM) and transmission electron microscopy (TEM). Texture development during deformation was analyzed by pole figure and orientation distribution function (ODF). The results indicated that: AZ31 magnesium alloys after 1 pass BP-ECAP, the ductility and strength were improved at same time, along with grains refined obviously; a new peak appeared in the (0002) pole figure of ECAP compared with that of BP-ECAP; TEM observation shows the prevailing of c+a dislocations and thus confirms the activation of c+a non basal slip by applying back pressure during ECAP; the simulation of stress-strain curve is baic consistent with measure result, which pro