In this study, the Ti6AI4V alloy, which is used as an implant material in the medical field, was joined with the laser welding method at different welding speeds. The bioactivity features of the Ti6AI4V alloy and its samples joined at different welding speeds were determined by immersing in a simulated body fluid (SBF) for 1, 7, 14, 21 and 28 days. The hydroxyapatite (HA) formation on the surfaces of the samples was determined by calculating the weight gain. The weight loss was calculated by removing the HA from the surface after bioactivity testing. The corrosion rates of the samples were also determined according to the weight loss. In addition, the characterization of the HA formed on the surfaces of the samples was performed. As a result of the investigations, it was determined that the increase in laser welding speed, and therefore the decrease in heat input, positively affected the bioactivity and biocorrosion features of the Ti6Al4V laser welded joints. It was determined that the particle sizes of the HAs of the laser weldments increased with lower heat inputs. It was also observed that the amount of HA nucleated on the laser-welded samples increased in accordance with the increase in the laser welding speed. The laser welded samples that were welded at higher welding speeds and therefore at lower heat inputs, exhibited better biocorrosion behaviors.

Graphic Abstract

中文翻译：

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激光焊接对Ti6Al4V接头体外生物活性的影响

在这项研究中，在医疗领域用作植入材料的Ti6Al4V合金，以不同的焊接速度与激光焊接方法结合在一起。通过将Ti6Al4V合金及其样品以不同的焊接速度连接在一起，将其浸入模拟体液（SBF）中1、7、14、21和28天来确定其生物活性。通过计算重量增加来确定在样品表面上的羟基磷灰石（HA）形成。通过生物活性测试后从表面去除HA来计算重量损失。还根据重量损失确定样品的腐蚀速率。另外，对在样品表面上形成的HA进行表征。调查的结果是，确定了激光焊接速度的提高，因此，热量输入的减少对Ti6Al4V激光焊接接头的生物活性和生物腐蚀特征产生了积极影响。可以确定，随着热量输入的减少，激光焊件的HA的粒径增加。还观察到，随着激光焊接速度的增加，在激光焊接的样品上成核的HA的量增加。以较高的焊接速度焊接，因此以较低的热量输入进行焊接的激光焊接样品表现出更好的生物腐蚀行为。还观察到，随着激光焊接速度的增加，在激光焊接的样品上成核的HA的量增加。以较高的焊接速度焊接，因此以较低的热量输入进行焊接的激光焊接样品表现出更好的生物腐蚀行为。还观察到，随着激光焊接速度的增加，在激光焊接的样品上成核的HA的量增加。以较高的焊接速度焊接，因此以较低的热量输入进行焊接的激光焊接样品表现出更好的生物腐蚀行为。

图形摘要