Diffusion Bonding and the Optimization of An Oxide Dispersion Strengthened Ni-base Alloy

氧化物弥散强化镍基合金的扩散连接及优化

基本信息

批准号：
08650097
负责人：
OKAZAKI Masakazu
金额：
$ 1.54万
依托单位：
Nagaoka University of Technology
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1996
资助国家：
日本
起止时间：
1996 至 1997
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08650097/
关键词：
Diffusion bonding Bonding Pressure Oxide dispersion strengthened Ni-base alloy Secondary recrystallization treatments Longitudinal joints Transverse joints Optimization High temperature fatigue strength L方向接合体

项目摘要

Diffusion bondings of an oxide dispersion strengthened Ni-base alloy, MA758 was studied, combining and controlling some bonding parameters and the microstructures. The high temperature fatigue strength of the joints optimized was also investigated, compared with those of base materials.The conclusion reached are sumarized as follows :(1) The post weld recrystallization treatment was found to be essential to improve the properties of the joints at high temperatures.(2) There is the best bonding pressure to obtain good joint : When the diffusion bondeing pressure was too low, non-bonded region remained. On the other hand, when it was too high, a non-recrystallized region with inadequately growing grains was retained at the welded interface, which reduced the mechanical properties of the joints.(3) The FEM analysis indicated that the retained non-recrystallized region show in the conclusion(2), must be resulted from the too large plastic deformation which would take away internal strain energy for adequate grain growth from the material. The shape of bonding component to avoid the retained non-recrystallized region was improved and proposed. The joints produced by employing the improved geometry and the optimum welding condition, revealed the fatigue strength almost comparable to that of the base material.

研究了氧化物弥散强化镍基合金MA758的扩散连接，结合并控制了一些连接参数和显微组织。还对优化后的接头的高温疲劳强度进行了研究，并与母材进行了比较。得出的结论如下：（1）焊后再结晶处理对于提高接头的高温疲劳性能至关重要。 (2)获得良好接头的最佳粘合压力：当扩散粘合压力太低时，会残留未粘合区域。另一方面，当它过高时，焊接界面处会保留晶粒长大不足的未再结晶区域，从而降低接头的力学性能。（3）有限元分析表明，保留的未再结晶区域结论(2)表明，一定是由于塑性变形过大而导致的，塑性变形会带走材料中晶粒充分长大的内部应变能。改进并提出了避免残留未再结晶区域的接合部件形状。采用改进的几何形状和最佳焊接条件生产的接头，其疲劳强度几乎与母材相当。