Materials Science

CLC number: TH117

Wear Properties of Ni₃Al-Ni₃V-Zr-Ni₅Zr Alloys under Different Atmospheres

不同气氛下Ni₃Al-Ni₃V-Zr-Ni₅Zr合金的磨损特性

Hunan Provincial Key Laboratory of Mechanical Equipment Health Maintenance, Hunan University of Science and Technology, Xiangtan 411201, Hunan, China

^† Corresponding author. E-mail: zhsh_w@sina.com

Received: 3 November 2023

Abstract

The study examines the friction and wear properties of Ni₃Al-Ni₃V-Zr-Ni₅Zr alloys under varying gas conditions. The alloy was tested in the presence of oxygen and carbon dioxide using a controlled atmosphere wear tester. The study revealed that the wear environmental embrittlement resulted from the diffusion of reactive atomic hydrogen into the interior of the Ni₃Al-Ni₃V alloy. The addition of Zr elements decreased the proportion of Al elements on the surface of the Ni₃Al-Ni₃V-Zr-Ni₅Zr alloy and reduced the proportion of H atoms produced by the chemical reaction between atmospheric water vapour and Al elements. This inhibited the environmental embrittlement and improved the performance of the Ni₃Al-Ni₃V-Zr-Ni₅Zr alloy. The wear performance of Ni₅Zr alloy is superior to that of Ni₃Al-Ni₃V. When exposed to air in an air environment, the surface of Ni₃Al-Ni₃V-Zr-Ni₅Zr alloy forms a protective Al₂O₃ oxide film on the workpiece, resulting in a reduction of the friction coefficient and wear rate of the alloy. The wear mechanism of the alloy is mainly oxidation wear and abrasive wear. In an oxygen environment, the surface of the alloy generates a significant amount of Al₂O₃ oxide film. The flaking of the oxide film leads to an increase in the friction coefficient and wear rate of the alloy. In a carbon dioxide environment, the surface of the alloy undergoes severe deformation, and plough lines become apparent. This is accompanied by flaking Si₃N₄ abrasive chips adhering to the surface of the alloy, which intensifies the wear of the alloy. The primary wear mechanism is abrasive wear. Therefore, the friction coefficient and wear rate of the Ni₃Al-Ni₃V-Zr-Ni₅Zr alloy in the atmosphere are optimal.

摘要

本研究探讨了Ni₃Al-Ni₃V-Zr-Ni₅Zr合金在不同气体条件下的摩擦和磨损特性。使用可控气氛磨损测试仪在氧气和二氧化碳存在的条件下对合金进行了测试。结果表明: 磨损环境致脆是由活性原子氢扩散进入Ni₃Al-Ni₃V合金内部引起的; Zr元素的加入贫化了Ni₃Al-Ni₃V合金表面的Al元素, 降低了大气中的水汽与Al元素结合产生H原子的比例, 抑制了环境致脆。大气中Ni₃Al-Ni₃V-Zr-Ni₅Zr合金表面暴露在空气中生成Al₂O₃氧化膜保护了工件, 使得合金摩擦系数和磨损率降低, 磨损机制主要为氧化磨损与磨粒磨损; 氧气气氛下, 合金表面生成大量Al₂O₃氧化物膜, 氧化物膜的剥落导致合金的摩擦系数和磨损率增加, 合金主要磨损机制为氧化磨损、粘着磨损与磨粒磨损; 二氧化碳环境下, 合金表面塑性变形严重, 犁沟明显, 伴随着剥落的Si₃N₄磨屑粘附在合金表面, 加剧了合金的磨损, 主要磨损机制为磨粒磨损; 因此, Ni₃Al-Ni₃V-Zr-Ni₅Zr合金在大气下的摩擦系数和磨损率最优。