improvement of Strength and Ductility of Ni_3Al and Challenge to a High Temperature Structural Material

Ni_3Al强度和延展性的提高及对高温结构材料的挑战

基本信息

批准号：
07555654
负责人：
AOKI Kiyoshi
金额：
$ 0.83万
依托单位：
Kitami Institute of Technology
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (A)
财政年份：
1995
资助国家：
日本
起止时间：
1995 至 1996
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07555654/
关键词：
Intermetallics Heat Resisting Alloys Mechanical Properties Alloy Design Mictrostructural Control Yield Strength Ductility Brittleness Ni_3Al ボロン破壊強度

项目摘要

Attempts have been made to improve the mechanical properties of Ni_3Al' because its yield strength is too low for using as a high temperature structural material. Solid solution hardening is one of the most fundamental and important strengthening methods. Many elements dissolve into Ni_3Al, but it is still uncertain whether Ni_3Al+M compounds are ductilized by microalloying with B.Particularly, it is interesting whether the deviation to the Ni-rich side is essential for ductilization of these alloys. In the present work, the effect of simultaneous alloying of B and the substitutional element M on ductilization of Ni_3Al has been investigated by the bend test and the tensile test. Ni_3Al is ductilized by macroalloying with Zr, Hf, V,NB,Mo, W,Co, Pd, Cu, Cr, Mn and Fe. The Ni_3 (Al, M) compounds, where M substitutes exclusively for the Al atoms, are ductilized by microalloying with B on the Ni-rich side. On the contrary, the (Ni, M)_3Al compounds and the (Ni, Mn)_3 (Al, Mn) compounds are ductilized by microalloying with B on both the Ni-rich and Al-rich sides. The yield strength of Ni_3Al+B increases by alloying with M except for Fe and Ga. The fracture strength of Ni_3Al+B increases by alloying with Pd, Ga, Si and Hf, but decreases with the other elements. Elongation of Ni_3Al+B increases by alloying with Ga, Fe and Pd, but decreases with other elements. Hf and Pd is the effective element for the increase of the yield strength and the fracture strength of Ni_3Al+B,respectively. Alloying with Hf leads to the increases of the yield strength and the fracture strength of Ni_3Al+B,but to the lowering of elongation. On the other hand, alloying with Pd improves all mechanical properties, i. e. the yield strength, the fracture strength and elongation. Alloying with Ti, V and Co leads to the lowering of mechanical properties of Ni_3Al+B.The reason why ductility of Ni_3Al+B is reduced by alloying with some elements M was discussed.

由于Ni_3Al'的屈服强度太低，不适合用作高温结构材料，因此人们尝试提高其力学性能。固溶强化是最基本、最重要的强化方法之一。许多元素溶解到Ni_3Al中，但Ni_3Al+M化合物是否可以通过B微合金化实现延展性仍不确定。特别是，向富Ni侧的偏离对于这些合金的延展性是否至关重要，这一点很有趣。本工作通过弯曲试验和拉伸试验研究了B和替代元素M同时合金化对Ni_3Al延展性的影响。 Ni_3Al 通过与 Zr、Hf、V、NB、Mo、W、Co、Pd、Cu、Cr、Mn 和 Fe 进行粗合金化而获得延展性。 Ni_3（Al，M）化合物（其中M仅取代Al原子）通过在富Ni一侧与B进行微合金化而延展。相反，(Ni，M)_3Al化合物和(Ni，Mn)_3(Al，Mn)化合物通过在富Ni侧和富Al侧均与B进行微合金化而塑化。 Ni_3Al+B通过与除Fe、Ga以外的M元素合金化而提高其屈服强度。与Pd、Ga、Si、Hf合金化时Ni_3Al+B的断裂强度提高，而与其他元素合金化则断裂强度降低。 Ni_3Al+B的伸长率随着Ga、Fe、Pd的合金化而增加，而随着其他元素的合金化而降低。 Hf和Pd分别是提高Ni_3Al+B屈服强度和断裂强度的有效元素。 Hf合金化使Ni_3Al+B的屈服强度和断裂强度提高,但延伸率降低。另一方面，与 Pd 合金化可改善所有机械性能，即： e.屈服强度、断裂强度和伸长率。 Ti、V、Co合金化导致Ni_3Al+B力学性能下降。讨论了合金化某些元素M降低Ni_3Al+B延展性的原因。