al2o3陶瓷与q235钢钎焊接头的微观组织与性能研究

1、河南科技大学 硕士学位论文 AlO陶瓷与Q235钢钎焊接头的微观组织与性能研究 姓名：王新阳 申请学位级别：硕士 专业：材料学 指导教师：李炎 20100101 摘 要 I 论文题目：论文题目：Al2O3陶瓷与 Q235 钢钎焊接头的微观组织与性能研究 专专 业：业：材料学 研研 究究 生：生：王新阳 指导教师：指导教师：李炎 教授 摘 要摘 要 实现 Al2O3陶瓷与 Q235 钢的可靠连接，既能发挥陶瓷材料优异的耐高温、 抗腐蚀及耐磨损等性能，又能充分利用金属材料易加工的特性，具有十分重要的 理论和实用价值。本文采用 Cu-Ti 钎料来钎焊连接 Al2O3陶瓷与 Q235 钢，研究 了 Cu-Ti 钎料对 Al2O3陶瓷的润湿性能，分析了钎料配比及钎焊工艺对接头组织 与性能的影响。采用扫描电镜、能谱仪、X 射线衍射仪、精密万能试验机等实验 设备重点研究了钎焊接头的微观组织和连接性能，并对界面性能及接头断裂模式 进行了探讨。 研究结果表明，钎料的配比直接影响 Cu-Ti 钎料对 Al2O3陶瓷材料的润湿性 能，在实验合金成分范围内，Ti 含量越高，钎料润湿性越好。钎料配比及钎焊 工艺

2、显著影响接头的微观组织与连接强度，使用不同配比钎料获得钎焊接头的界 面组织不同，导致接头强度差别较大；钎焊温度过高或过低，保温时间过长或过 短均不利于得到组织致密、性能良好的钎焊接头。使用 Cu75Ti25(at%)钎料，在 1050保温 30min 时，施加 74kPa 的钎焊压力能获得最佳的钎焊接头：界面结 合区组织致密，裂纹、微孔缺陷较少，接头抗剪强度达到 99.3MPa。 对钎焊接头显微结构分析表明，界面结合区分为三层，即钎料金属与陶瓷形 成的反应层、中间钎料层以及钢侧过渡层；在界面结合区生成有 Cu 基固溶体、 Cu3Ti3O、TiFe、TiFe2新相；陶瓷与金属间实现了良好的冶金结合。 对钎焊接头界面性能研究表明：界面区显微硬度值高于 Q235 钢，界面显微 硬度平缓过渡，接头性能良好。不同结合强度的钎焊接头具有不同的剪切断口特 征，接头的断裂模式有两种：一类是高强度断裂，断裂全部发生在陶瓷一侧；一 类是低强度断裂，断裂发生在陶瓷与金属界面处。 关关 键键 词：词：Cu-Ti 钎料，Al2O3陶瓷，Q235 钢，钎焊界面，接头性能 论文类型：论文类型：基础研究 摘要 II

3、Subject: Microstructures and Properties of Brazing Joint of Al2O3 Ceramic and Q235 Steel Specialty: Materials Science Name: Wang Xin-yang Supervisor: Professor Li Yan ABSTRACT To achieve a solid connection between Al2O3 ceramics and Q235 steel can play the excellent high-temperature performance, corrosion resistance, wear resistance of ceramic materials, and can also take full advantage of easy processing characteristics of metallic materials, which is extremely important in both theory and prac

4、tice. In this research, Al2O3 ceramics were bonded with Q235 steel by active brazing with the filler alloys of Cu-Ti. The wetting properties of Cu-Ti active filler alloy were studied, and effects of the composition of filler alloys and brazing parameters such as temperature, holding time on joining strength and interface microstructures were investigated and analyzed by means of SEM、EDS、XRD and precision universal testing machine, etc. The interfacial properties and the fracture model of the joi

5、nts were also discussed. The experimental results showed that the content of Ti in filler had an immediate impact on the wettability of the filler alloy, and the wettability increased with increasing Ti content in the experimental alloy composition range. The microstructure and properties of the joint depended on the composition of filler alloy and brazing parameters. Different shear strength of the joints was obtained as a result of different interface microstructures when using filler alloys w

6、ith different ratios. Too high or too low brazing temperatures and too long or too short holding times were not conducive to obtain joints with good performance and compact organizations. When brazed at 1050 for 30min with a filler alloy of Cu75Ti25 and exerted a pressure of 74Pa, a best joint was obtained with compact and few defects such as cracks and micropores in the interfacial-binding region and the average shear strength of the joint is 99.3MPa. The analysis of microstructure of the joint

7、s showed that interface-binding region could be divided into three layers. The three layers were reaction layer close to the ceramic, brazing alloy layer and diffusion layer close to the steel. The liquid braze alloy filled the micropores of ceramic and formed the reaction layer. Cu3Ti3O, TiFe, TiFe2 and Cu-base solid solution were confirmed as the reaction products. A 摘要 III metallurgical bonding had been achieved between the ceramics and the steel. According to the research of interfacial prop

8、erties of the brazed joint, the hardness of interfacial zone was higher than the Q235 steel, and the hardness of the interfacial zone smoothed their transition, which indicated an excellent joint. Different bonding strength of brazed joints showed different characteristics of the shear fracture. There were two fracture modes of the joints, when the bonding strength was high, the fracture occurred in the ceramic side completely, when the bonding strength was low, the fracture occurred in the inte

9、rface of ceramic and metal. KEY WORDS: Cu-Ti filler alloy, Al2O3 ceramics, Q235 steel, brazing interface, joint properties Dissertation Type: Fundamental research 第 1 章 绪论 1 第1章 绪论第1章 绪论 1.1 引言引言 材料、能源、信息是现代技术的三大支柱，而能源和信息的发展，在一定程 度上又依赖于材料的进步。例如：要提高热机效率，必须提高工作温度，所以要 求制造热机的材料在高温下具有足够的强度、韧度、耐热性。这是一般钢铁材料 无法达到的。而用新型陶瓷材料制成的高温结构陶瓷柴油机可节油 30%，热机 效率可提高 50%。可见，开发新材料可提高现有能源的利用率1。 随着冶金、矿山、电力、航空等行业的发展，金属耐磨材料的应用环境越来 越苛刻，苛刻条件下材料的摩擦、磨损、氧化尤为严重。而陶瓷材料具备耐腐 蚀、耐磨损、高硬度、抗氧化等优点2,3，可部分取代金属耐磨材料加以应用。 但由于陶瓷加工性能差，延展性和冲击韧性低，易脆，使陶瓷材料在耐磨领域中 的应用受到严重制约。采用陶瓷-金属连接技术制备复合构件，既可以利用金属 的强韧性，又可以充分发挥陶瓷材料的高硬度、高耐磨性的优点，实现二者的优 势互补。近年来，国内外材料工作者逐渐把陶瓷-金属的连接作为尖端技术列入 其主要研究范畴4-6。进一步研究和开发新型高硬抗磨陶瓷-金属复合材料，研究 陶瓷-金属连接技术及其连接机理，对于整个社会经济的发展具有重要的意义， 不仅符合国家产业政策，同时也有着很广泛的应用前景。 陶瓷的种类很多，目前常用的能与金属连接的陶瓷按其组成不同可分为氧化 物陶瓷和非氧化物陶瓷两大类。氧化物陶瓷中应用最广泛的是 Al2O3陶瓷。 Al2O3陶瓷具有机械强度高、绝缘电阻大、硬度高、耐磨、耐高温及耐腐蚀等一 系列优异性能，广泛应

《al2o3陶瓷与q235钢钎焊接头的微观组织与性能研究》由会员E****分享，可在线阅读，更多相关《al2o3陶瓷与q235钢钎焊接头的微观组织与性能研究》请在金锄头文库上搜索。