纳米氧化铝弥散强化铜涂层硬度的研究

采用大气等离子喷涂制备了氧化铝弥散强化铜涂层,对涂层2小时600℃真空热处理前后的硬度进行了对比,并对涂层显微组织进行了分析。结果表明,热处理前后涂层的硬度基本没有发生变化,宏观硬度平均值在83HR15Y～84HR15Y之间,显微硬度平均值在216HV0.05～219HV0.05之间。涂层中纳米氧化铝颗粒均匀分布,尺寸在40～200nm之间。纳米弥散强化颗粒对位错的阻碍作用是涂层硬度保持不变的主要原因,而影响弥散强化效果的主要因素是颗粒尺寸和弥散分布程度。

Study on the Hardness of Nano-Al_2O_3 Dispersion-strengthened Copper Coating

Al2O3 dispersion-strengthened copper coating is deposited by air plasma spraying system. After 2 hours vacuum heat treatment at 600℃,the coating hardness is measured and compared with the hardness before vacuum heat treatment,the microstructure of the coating is studied too. The result shows that the hardness does not change after the vacuum heat treatment. The macro-hardness average is 83HR15Y～84HR15Y and the micro-hardness average is 216HV0.05～219HV0.05. Nano-alumina particles distribute uniformly in the coating with the size 40～200 nm. The main reason of unchanged hardness is the effect of nano-particle on the dislocation. The particle size and the degree of homogeneous distribution are the main factors that decision the dispersion strengthening effectiveness.