【作者】 孔纪兰；

【导师】 周上祺；

【作者基本信息】 重庆大学 ， 材料学， 2002， 硕士

【摘要】 铍属稀有金属，因其具有密度低，比强度和比热容高以及导热性好等优点，被广泛用于核能、航空和航天工业。铍的缺点是延性差，脆性大，从而给铍构件的设计和制造带来不少困难。另外，铍的化学活性高，在高温下极易氧化，还与其它许多金属反应生成脆性的金属间化合物，影响构件的性能和使用寿命，因而研究铍/不锈钢热静压扩散连接工艺、成分、组织、结构与性能的关系，具有重要的理论意义和实用价值。论文得出以下结论：1）经剥层X射线物相鉴定表明，扩散连接区的主要物相为α-Be, 有少量的金属间化合物B11Fe、Be5Fe和FeBe2及α-Fe，也有微量的Be21Ni、Be12Cr、MoBe12和BeO。2）铍/不锈钢扩散连接区的显微组织，可粗略的地划分为三个白亮带区，一个暗区、三个黑白相混合的带状区，带的纵向都大致垂直于外加应力方向。3） 白亮带区主要是金属间化合物，黑白相间的区域为两相区，暗区为α-Be。4） 俄歇谱上的台阶与金属间化合物相对应。5） 扩散连接区因生成金属间化合物而变脆，硬度特别高，耐蚀性也比较好。6） 热静压过程中，沿晶扩散的速度远大于晶内扩散，因此，金属间化合物主要分布在晶界。7）用计算机模拟的热等静压试样的成分分布，与实测值比较吻合，计算机是优化热静压的重要手段。更多还原

【Abstract】 Metal beryllium has widely applied to industry of nuclear, space flight and airplane due to the characteristic of low density, high strength ratio, high specific heat and excellent property of heat. But beryllium’s high brittleness and low ductibility bring its component’s design much difficulty. Furthermore, beryllium is an active element, which is prone to be oxidized especially at high temperature and react with many other metals to form brittle intermetals, which influence the component’s use and life. Bonding beryllium with HR-1 stainless has important significance and great-applied value, but the numbers .It has been showed aboard that it is very difficult to bond beryllium with stainless steel due to weld stress and crackle resulting from brittle inter-phase has not studied it in China. Diffusion bonding and brazing may be good methods to bond beryllium with HR-1 stainless successfully, but choosing the perfect technological parameter, interlayer and characterizing bonding interface for bonding be with HR-1 stainless have great difficulty. The diffusion and brittle-phase formation mechanics is ambiguous, and the model of diffusion concentration field isn’t reported in document. So researching the diffusion bonding between be and HR-1 stainless plays an important role in production and practice, especially studying the relationship among diffusion bonding technics, component, structure and performance. In this paper, Be and HR-1 stainless steel are bonded by diffusion bonding and brazing. The following conclusions may be obtained:1)X- radial phase analysis after peeling shows that the diffusion bonding area consists of α-Be mostly and a little intermetals, such as Be11Fe, Be5Fe, FeBe2, Be21Ni5, Be12Cr,MoBe12 etc.α-Fe and BeO also exist。2) The microstructure in the diffusion bonding area forms three white area, a dark area and three area in which white and black coexist.3) The white area mainly consists of intermetals and them distribute on grain boundary. In the dark area ,α-Be is the most component. While the white and black coexisting area is two phase area. 4) The sidesteps in the AES correspond with intermetals.5) The diffusion bonding area become much brittler and has high hardness and good capability to corrosion because of intermetals and solid solution existing. 6) During the process of hot pressing, the diffusion rate on the grain boundary is bigger than the inner grain ones. The intermetals mainly lie on grain boundary.<WP=6>7) The simulation of concentration profile for the HIP and hot pressing specimen accords with the experiment profile. The computer is a good tool to optimize technology parameters.更多还原