Development of Heat Resistant Ni_3Al Base Cermet Using Mechanical Alloying Process.

采用机械合金化工艺开发耐热Ni_3Al基金属陶瓷。

• 批准号: 05650684
• 负责人: YAMAZAKI Michio
• 金额: $ 1.41万
• 依托单位: THE Nishi-Tokyo University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1993
• 资助国家: 日本
• 起止时间: 1993 至 1994
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-05650684/
• 关键词: Ni_3Al; mechanical alloying; TiC; cermet; powder metallurgy; intermetallics; superplasticity; oxidation test; サーメット; メカニカルアロイング

Ni_3Al (Ni-24.5 mol%Al-0.3mol%B) matrix composite alloys with 20,40,60 and 80vol%TiC particles and a matrix alloy with 0vol%TiC were produced by mechanical alloying - hot press process using pure Ni, pure Al and TiC powders. Details of phenomenon like morphological change of powders during mechanical alloying process were studied. Also, the microstructures and the mechanical properties as well as the oxidation properties of sintered specimens were investigated. Fine powder particles with diameter of less than 10mum were produced by mechanical alloying. Sintered composite alloys were found that they consist of Ni_3Al matrix with small amount of Ni solid solution and uniformly dispersed TiC particles. Although the plastic strain was observed for the 0vol% - 40vol%TiC alloys at any temperature investigated, 60vol% and 80vol%TiC alloys deformed plastically only at higher temperatures than 673K and 1073K,respectively. The flow stresses for alloys with 0vol% - 40vol%TiC exhibited the plateau region from 400K to 700K,and then decreased markedly. It was revealed that the strain rate sensitivity exponent (m value) for the base matrix alloy was over 0.4, indicating the development of superplastic deformation. On the other hand, the composite alloys with TiC particles showed lower m values than 0.3. Mass gain during oxidation test at 1273K increased with TiC volume fraction. While the thickness of the scale observed for the matrix alloy was very thin and composed of only Al_2O_3, TiC containing alloy formed the thick scale consisting of both Al_2O_3 and TiO_2.

以纯Ni、纯Al和TiC粉末为原料，采用机械合金化-热压工艺制备了TiC含量分别为20、40、60和80vol%的Ni_3Al（Ni-24.5mol%Al-0.3mol%B）基复合合金和TiC含量为0vol%的Ni_3Al基合金。研究了机械合金化过程中粉末形貌变化等现象。研究了烧结试样的显微结构、力学性能和氧化性能。通过机械合金化制备了直径小于10 μ m的细粉末颗粒。烧结复合合金由Ni_3Al基体和少量Ni固溶体及均匀弥散分布的TiC颗粒组成。0vol%~ 40vol%TiC合金在任何温度下都能观察到塑性变形，而60vol%TiC和80vol%TiC合金分别在高于673 K和1073 K的温度下才发生塑性变形。TiC含量为0vol%~ 40vol%的合金在400 ~ 700 K的流变应力呈现平台区，然后显著下降。结果表明，基体合金的应变速率敏感性指数（m值）大于0.4，表明超塑性变形的发展。另一方面，具有TiC颗粒的复合合金显示出低于0.3的m值。在1273 K的氧化试验过程中的质量增益增加与TiC的体积分数。基体合金氧化膜厚度很薄，仅由Al_2O_3组成，而含TiC的合金则形成了由Al_2O_3和TiO_2组成的厚氧化膜。

项目成果

S.Ochiai and M.Yamazaki: "Microstructures and Mechanical Properties of Ni_3Al-TiC Composite" J.Jpn.Soc.Powder and powder Metallurgy. (to be published).

S.Ochiai 和 M.Yamazaki：“Ni_3Al-TiC 复合材料的显微组织和机械性能”J.Jpn.Soc.Powder and Powder Metallurgy。