摘要本次毕业设计主要研究Cu-15Ni-8Sn合金材料在均匀化退火、固溶处理、冷变形、时效处理这几种情况下金相组织的变化。处理方法的不同对合金材料的性能影响也不同，用蔡司显微镜放大50到100倍观察合金晶界组织的变化，用扫描电镜观察晶粒在放大2000倍的条件下相变化及其中能谱分析，用洛氏和维氏硬度仪测量材料经过不同条件处理后的硬度变化。86645

通过观察金相组织分析得出Cu-15Ni-8Sn合金在铸态下，其晶粒呈现出明显的树枝状，白色组织物为贫Sn富Ni的Cu-Ni固溶体，掺杂在晶界处发亮的白色物为富Sn相，属于偏析现象。通过均匀化退火及固溶处理后使得Sn的偏析得到有效的改善。

本文对Cu-15Ni-8Sn合金采用的变形方式为冷压变形，通过控制对合金的不同压下量从而来达到控制材料变形量的效果。最终测量出不同变形量条件下的合金硬度及强度，分析结果发现合金的硬度、强度均与材料的变形量有着很大关系。对冷变型之后的Cu-15Ni-8Sn合金进行时效处理，合金的组织性能相对于之前也有了大幅度改善。不同时间不同温度的时效处理也对材料性能有关，最终选出最适合的时间温度时效（430℃×2h）后Cu-15Ni-8Sn合金材料的组织更加均匀致密（此时硬度38。4HRC强度为1169MPa），综合性能更加良好。

毕业论文关键词：Cu-15Ni-8Sn合金、均匀化退火、时效处理、金相组织

Abstract  This graduation design mainly research Cu-15Ni-8Sn alloy materials in the homogenizing annealing, solid solution treatment, cold deformation, aging treatment under these aspects change in the microstructure。 Processing methods of different alloy materials affect the performance of different, Zeiss microscope with zoom 50-100 times observe the changes in the organization of the alloy grain boundaries,Observed in a scanning electron microscope at 2000 times grain phase change and energy spectrum analysis, Rockwell hardness tester for measuring material after the hardness variation after different treatments。 

By observing microstructure analysis drawn Cu-15Ni-8Sn alloy cast under its dendritic grains showing a clear, white tissue was lean Sn Ni-rich Cu-Ni solid solution doped hair at the grain boundaries bright white object as Sn-rich phase，is segregation。After processing through homogenization and solution so that Sn segregation effectively improved。

In this paper, the deformation of Cu-15Ni-8Sn alloy is used as a cold press。By controlling the alloy to achieve the reduction of different control material deformation effect。 The final measure of hardness and strength under different deformation conditions, the analysis found that the alloy hardness, strength both have a great relationship with the amount of deformation of the material。 Of Cu-15Ni-8Sn alloy cold variant after aging treatment, microstructure and properties of alloys has also been greatly improved relative to before。 Different temperatures at different times of aging treatment on the material properties also relevant, choose the most appropriate time and temperature obtained after aging tissue Cu-15Ni-8Sn alloy material is more uniform and dense, more comprehensive performance is good。

Keywords:Cu-15Ni-8Sn alloy，homogenizing annealing, aging treatment, microstructure

目  录

第一章 绪论 1

1。1 引言 1

1。2 铜基合金发展概况 1

1。2。1 铍青铜发展历史 1

1。2。2 铜基合金的发展 2

1。3铜基合金分类 2

1。3。1 低温退火强化型