Cold spray (CS) has been deployed to deposit compact and well bonded Ti-6Al-4 V (Ti64) coatings. While the effects of gas pressure, gas temperature and powder feed rate have been well studied, the influence of spray angle during CS deposition of Ti64 powders is less understood. As actual components frequently have uneven or curved surfaces, it is critical to understand the impact of spray angle to design an efficient toolpath for repair or additive manufacturing of 3D freeform objects. In this work, off-normal spray angles were studied to elucidate their impact on the coating quality when depositing spherical Ti64 powders by CS on Al6061-T6 substrates using nitrogen as process gas. Evaluation of deposition efficiency and the coatings' surface roughness, cross-sectional microstructure, thickness and residual stress were performed to provide insight on the effects of spray angle. Finite Element Method (FEM) simulations were also performed in order to understand the dominant Ti64 deformation mode and development of residual stress in the coatings. Spray angle is identified to be an effective process parameter to control porosity, pore alignment and extent of surface compressive residual stress in the CS deposited materials.

冷喷涂 (CS) 已用于沉积致密且结合良好的 Ti-6Al-4 V (Ti64) 涂层。虽然气体压力、气体温度和粉末进料速率的影响已经得到了很好的研究，但在 Ti64 粉末的 CS 沉积过程中喷射角度的影响却鲜为人知。由于实际组件经常具有不平坦或弯曲的表面，因此了解喷射角度的影响以设计用于修复或增材制造 3D 自由曲面对象的有效刀具路径至关重要。在这项工作中，研究了非正常喷射角度，以阐明在使用氮气作为工艺气体通过 CS 在 Al6061-T6 基材上沉积球形 Ti64 粉末时它们对涂层质量的影响。评估沉积效率和涂层的表面粗糙度、横截面微观结构、对厚度和残余应力进行了分析，以深入了解喷射角度的影响。还进行了有限元法 (FEM) 模拟，以了解主要的 Ti64 变形模式和涂层中残余应力的发展。喷雾角度被认为是控制 CS 沉积材料中的孔隙率、孔隙排列和表面压缩残余应力范围的有效工艺参数。