Tantalum coatings have wide applications including as corrosion resistant coatings and radiopaque films for biomedical implants. However, producing coatings of sufficient thickness with the desired mechanical properties remains a substantial challenge. In this study, we show that the microstructure and properties of thick Ta films deposited on NiTi wires can be controlled significantly by pre-treating the substrate surface via ultrasonication followed by Aqua Regia etchant, or by plasma-based etching alone, while maintaining overall adhesive strength. Films from plasma and chemically etched samples exhibited substantially greater bulk texturing in the <111> direction than the control film, also yielding more elongated and columnar grains. The extent of <111> texturing in each sample was reflected in differences in Σ3 CSL boundary density. Additionally, only plasma etching yielded a β-Ta secondary phase. These microstructural observations demonstrate that film phase composition, texturing, grain shape distribution and grain boundary characteristics can be optimised for particular applications, simply by applying different NiTi substrate pretreatment regimes. It is suggested that this bears significant implications for influencing bulk properties such as cohesive and shear strength, as well as ductility, conductivity and cohesion in thick tantalum coatings.

钽涂层具有广泛的用途，包括用作生物医学植入物的耐腐蚀涂层和不透射线的薄膜。然而，生产具有所需机械性能的足够厚度的涂层仍然是一个巨大的挑战。在这项研究中，我们表明沉积在NiTi导线上的厚Ta膜的微观结构和性能可以通过超声处理，随后使用Aqua Regia蚀刻剂或仅通过基于等离子体的蚀刻对基板表面进行预处理，同时保持整体粘合性而得到显着控制。力量。来自等离子和化学蚀刻样品的薄膜在<111>方向上显示出比对照薄膜大得多的整体纹理，也产生了更多的细长晶粒和柱状晶粒。<111>的程度 每个样品的织构反映在Σ3CSL边界密度的差异上。另外，仅等离子体蚀刻产生β-Ta次级相。这些微观结构观察表明，只需应用不同的NiTi基板预处理方案，即可针对特定应用优化膜相组成，织构，晶粒形状分布和晶界特征。建议这对影响体积性质（如内聚和剪切强度）以及厚钽涂层的延展性，电导率和内聚力具有重要意义。只需应用不同的NiTi基板预处理方案，即可针对特定应用优化晶粒形状分布和晶界特性。建议这对影响体积性质（如内聚和剪切强度）以及厚钽涂层的延展性，电导率和内聚力具有重要意义。只需应用不同的NiTi基板预处理方案，即可针对特定应用优化晶粒形状分布和晶界特性。建议这对影响体积性质（如内聚和剪切强度）以及厚钽涂层的延展性，电导率和内聚力具有重要意义。