【作者】 孙超；

【导师】 王国峰；

【作者基本信息】 哈尔滨工业大学 ， 材料加工工程， 2014， 硕士

【摘要】 航空发动机是飞机的重要组成部分，发动机的性能直接影响着整个飞机的使用性能，发动机的减重能够提高推重比，而空心结构的叶片能够减少发动机的整体重量。因此，采用扩散连接-超塑成形技术成形的中空叶片在发动机减重方面具有重要的意义。本文对钛合金中空叶片的扩散连接-超塑成形工艺进行研究。通过TC4钛合金的高温拉伸实验，得到了最优的材料变形温度，材料的应变速率敏感系数m及k值。研究了TC4三层板的扩散连接，热成形，超塑成形工艺；成形出质量较好的钛合金中空叶片，同时将电流辅助成形与扩散连接-超塑成形结合起来，对电流辅助扩散连接工艺进行研究，分析了电流辅助扩散连接相比于传统扩散连接的优势。首先对TC4板材进行高温拉伸实验，该板材在920℃具有最大的延伸率800%，确定最佳的成形温度及该温度下材料的参数。采用传统的加热炉加热的方式进行中空叶片的扩散连接-超塑成形实验，确定了最优的实验参数，成形出较好的中空叶片；分析了叶片芯板的壁厚分布以及上下面板与芯板的连接情况，线扫描分析了扩散连接的接头，判断了扩散连接的接头的质量。采用电流辅助扩散连接，确定了实验的温度，得到该温度下电流，压力，保温时间等参数；通过对面板与芯板的连接情况进行分析，探究了扩散连接的压力，保温时间对扩散连接接头质量的影响；比较了电流辅助扩散连接与加热炉加热扩散连接，探究了两种工艺在加热时间以及晶粒变化上的差别。更多还原

【Abstract】 Engine is the essential components to the aviation aircraft parts, the property ofaviation aircraft depends largely on the level of the engine, thrust-weight ratio isone of the most important indicators that reflects the level of engine, the weight lossof engine can improve thrust-weight ratio, and hollow blade can reduce the weightof the engine, so the DB-SPF of hollow blade is of great importance to weight lossof engine.In this paper， the DB-SPF of hollow blade were studied. Through the hightemperature tensile experiment of TC4titanium alloy, the best material deformationtemperature could be obtained, the strain rate sensitivity m and k could also be got.The DB，hot forming and SPF of TC4titanium alloy were studied and the bettertitanium alloy hollow blade was formed； at the same time, the current auxiliaryforming and SPF/DB was combined and the current auxiliary diffusion bondingwere studied and the advantages of the current auxiliary diffusion bondingcompared to traditional diffusion bonding were analysed.Firstly, through the high temperature tensile experiment of TC4titanium alloy,the best elongation appeared when the temperature was920℃and the bestelongation was800%, the optimum forming temperature and the parameters of thematerial at this temperature were confirmed. Through the DB，hot forming and SPFof TC4titanium alloy,the hollow blade was formed, the optimum experimentalparameters was determined, the better hollow blade was formed, the thicknessdistribution of core plate and the connection of the panel and core plate wasanalyzed, through the line scanning analysis of the diffusion bonding joint, thequality of the diffusion bonding joint was judged.Through the current auxiliary diffusion bonding, the temperature wasconfirmed，and the current size, pressure, heat holding time and other parameterswas identified; the connection of the panel and core board were analyzed, thepressure of the diffusion bonding and the time of heat holding time on the quality ofthe diffusion bonding joints were explored，the current auxiliary diffusion bonding and the traditional diffusion bonding was compared, the difference of two kindsprocess on the heating time and the change of grain size were explored.更多还原