球磨纳米结构Fe40Al合金粉末及其冷喷涂沉积行为研究

发布时间：2018-10-10 20:36

【摘要】：目的研究冷喷涂用纳米结构Fe40Al合金粉末的球磨制备工艺及其在不同基体表面的冷喷涂沉积行为。方法以Fe粉、Al粉为原料,按照Fe-40Al进行配比混合,采用行星式球磨机制备纳米结构Fe40Al合金粉末,在不同硬度基体表面(不锈钢、低碳钢、纯铜及锡)冷喷涂沉积单个Fe40Al合金粉末颗粒。采用X射线衍射仪(XRD)、扫描电子显微镜(SEM),分析球磨过程中Fe40Al合金粉末的组织结构演变规律、粉末颗粒在不同基体表面的碰撞变形行为及沉积特性。结果球磨过程中,随着球磨时间的延长,Al扩散进入Fe晶格形成纳米结构Fe(Al)固溶体,球磨36 h后,Fe40Al合金粉末的晶粒尺寸约为35 nm,平均颗粒尺寸约为20μm,内部为精细层状结构。纳米结构Fe40Al合金粉末在硬度较高的不锈钢和低碳钢基体上沉积时,粉末颗粒发生强塑性变形而基体变形量较小,颗粒和基体间的结合较弱,沉积效果较差;当在硬度较低、塑性较好的Cu基体上沉积时,基体与粉末颗粒同时发生塑性变形,颗粒和基体间的结合较强,沉积效果最好;在硬度最低的Sn基体上沉积时,基体发生强烈的塑性变形且出现部分熔化,但颗粒几乎没有变形,且颗粒与基体间的结合很弱,沉积效果最差。结论采用球磨工艺可制备出适合冷喷涂用的纳米结构Fe40Al合金粉末,随着球磨时间的延长,粉末晶粒尺寸减小,硬度增加。基体种类对纳米结构Fe40Al合金粉末的冷喷涂沉积行为影响显著,基体硬度过高或过低均不利于粉末颗粒沉积,基体与粉末颗粒同时发生塑性变形有利于增强颗粒与基体间的界面结合,从而改善沉积效果。
[Abstract]:Objective to study the preparation process of nano-structure Fe40Al alloy powder for cold spraying and its deposition behavior on different substrate surfaces. Methods using Fe powder and Al powder as raw materials, the nano-structure Fe40Al alloy powder was prepared by planetary ball mill according to the ratio of Fe-40Al. The nano-structure Fe40Al alloy powder was prepared on the surface of different hardness matrix (stainless steel, low carbon steel). Single Fe40Al alloy powder particles were deposited by cold spraying of pure copper and tin. X-ray diffractometer (XRD),) scanning electron microscope (SEM),) was used to analyze the microstructure evolution of Fe40Al alloy powder during ball milling, the impact deformation behavior and deposition characteristics of the powder particles on different substrate surfaces. Results during ball milling, Al diffused into Fe lattice to form nanostructured Fe (Al) solid solution with the prolongation of milling time. After 36 h ball milling, the average grain size of Fe40Al alloy powder was about 20 渭 m and the average grain size was about 20 渭 m at 35 nm, with fine lamellar structure inside. When nano-structure Fe40Al alloy powder is deposited on stainless steel and low carbon steel with high hardness, strong plastic deformation occurs in powder particles and the amount of matrix deformation is small, the bonding between particles and matrix is weaker, and the deposition effect is poor, when the hardness is low, When deposited on the Cu matrix with good plasticity, the matrix and the powder particles have plastic deformation at the same time, the bonding between the particles and the matrix is stronger and the deposition effect is the best, and when the substrate is deposited on the Sn matrix with the lowest hardness, The matrix has strong plastic deformation and partial melting, but the particle has almost no deformation, and the bonding between the particles and the matrix is very weak, and the deposition effect is the worst. Conclusion Nanostructured Fe40Al alloy powder suitable for cold spraying can be prepared by ball milling process. With the prolongation of milling time, the grain size of the powder decreases and the hardness increases. The effect of matrix type on the deposition behavior of nano-structure Fe40Al alloy powder by cold spraying was significant, and too high or too low substrate hardness was not conducive to powder particle deposition. The plastic deformation of the matrix and powder particles at the same time is beneficial to enhance the interfacial bonding between the particles and the matrix, thus improving the deposition effect.
【作者单位】：九江学院;西安交通大学;
【基金】：国家自然科学基金项目(51001056,51561013) 江西省自然科学基金项目(20151BAB206008) 江西省科技落地计划项目(KJLD12096)~~
【分类号】：TG174.442

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