采用动态图像分析技术对高温合金粉末形状定量表征

Quantitative Characterization of Superalloy Powder Particle Shape Using Dynamic Image Analysis Technique

摘要:

采用场发射扫描电子显微镜（FE-SEM）和动态图像分析（DIA）技术，选用8个形状参数对高温合金粉末形状进行了定性及定量表征。结果表明，Krumbein球形度（SPHT_K），长宽比（AR），紧凑度（Compct）和Krumbein圆润度（RDNS_C）对高温合金粉末形状具有显著的区分度，可以作为粉末形状表征的关键参数使用。此外，发现圆度（C）、球形度（SPHT）、SPHT_K三者之间的区分度依次增加，尤其是SPHT_K的区分度最高。通过对比8个形状表征参数的区分度差异，发现C、SPHT，凹凸度（Conv_A）和坚固性（Solid）的区分度并不显著。最终，将SPHT_K，AR，Compct和RDNS_C 4个参数组合用于定量表征高温合金粉末颗粒形状变化，为雾化参数的有效调整提供粉末形状的定量表征依据，促进增材制造和先进粉末冶金技术的研发。

Abstract:

Eight shape parameters were selected to qualitatively and quantitatively characterize the particle shape of superalloy powders using field emission scanning electron microscopy (FE-SEM) and dynamic image analysis (DIA) technique. The results show that Krumbein sphericity (SPHT_K), aspect ratio (AR), compactness (Compct) and Krumbein roundness (RDNS_C) demonstrate a significant distinction degree of superalloy powder particle shape, and can be used as critical parameters for the characterization of particle shape.In addition, the distinction degree of circularity (C), sphericity (SPHT) and SPHT_K increases gradually. In particular, the SPHT_K has the highest distinction degree among the three shape parameters. By comparing the difference in distinction degree among eight shape parameters, it is found that the distinction degree of circularity (C), sphericity (SPHT), convexity (Conv_A) and solidity (Solid) is not significant.Therefore, the SPHT_K, AR, Compct and RDNS_C are selected as the shape parameter combination to quantitatively characterize the particle shape. The combination of these four shape parameters can be used to quantitatively characterize the change of superalloy powder particle shape. Meanwhile, it provides a data basis to effectively optimize the atomization processing parameters. The promotion of the development of additive manufacturing and advanced powder metallurgy technology in future was discussed in the end.