Critical Deposition Condition of CoNiCrAlY Cold Spray Based on Particle Deformation Behavior
Critical Deposition Condition of CoNiCrAlY Cold Spray Based on Particle Deformation Behavior
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DOI：
10.1007/s11666-016-0477-6
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发表时间：
2017-02
影响因子：
3.1
通讯作者：
Y. Ichikawa;K. Ogawa
中科院分区：
文献类型：
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作者：
Y. Ichikawa;K. Ogawa
先前的研究表明，通过冷喷涂工艺沉积mccraly涂层；然而，冷喷涂的沉积机理尚未得到明确的解释，只能用冲击速度进行经验描述。本研究的目的是阐明临界沉积条件。将颗粒沉积尺寸的微观实验测量与数值模拟相结合，研究了颗粒的变形行为。通过扫描电子显微镜对聚焦离子束制备的沉积颗粒截面进行分析，确定了尺寸参数，以描述沉积阈值。从Johnson-Cook有限元模拟结果来看，尺寸参数与冲击速度有直接的相关性。因此，临界速度可以描述沉积阈值。此外，最大等效塑性应变也强烈依赖于冲击速度。因此，颗粒沉积所需的阈值条件可以用颗粒和基体的等效塑性应变来表示。对于类似材料的颗粒-衬底组合，衬底更难以变形。因此，本研究确定了冷喷涂过程中颗粒沉积的主导因素是基体在冲击和变形过程中产生的最大等效塑性应变。
Previous research has demonstrated deposition of MCrAlY coating via the cold spray process; however, the deposition mechanism of cold spraying has not been clearly explained—only empirically described by impact velocity. The purpose of this study was to elucidate the critical deposit condition. Microscale experimental measurements of individual particle deposit dimensions were incorporated with numerical simulation to investigate particle deformation behavior. Dimensional parameters were determined from scanning electron microscopy analysis of focused ion beam-fabricated cross sections of deposited particles to describe the deposition threshold. From Johnson-Cook finite element method simulation results, there is a direct correlation between the dimensional parameters and the impact velocity. Therefore, the critical velocity can describe the deposition threshold. Moreover, the maximum equivalent plastic strain is also strongly dependent on the impact velocity. Thus, the threshold condition required for particle deposition can instead be represented by the equivalent plastic strain of the particle and substrate. For particle-substrate combinations of similar materials, the substrate is more difficult to deform. Thus, this study establishes that the dominant factor of particle deposition in the cold spray process is the maximum equivalent plastic strain of the substrate, which occurs during impact and deformation.