Department of Biomedical Materials Science, School of Dentistry, University of Mississippi Medical Center, Jackson, Mississippi, USA.
J Biomed Mater Res B Appl Biomater. 2013 Jan;101(1):124-30. doi: 10.1002/jbm.b.32825. Epub 2012 Oct 17.
Customized one-component dental implants have been fabricated using Electron Beam Melting(®) (EBM(®)), which is a rapid prototyping and manufacturing technique. The goal of our study was to determine the effect of electron beam orientation on the fatigue resistance of EBM Ti-6Al-4V ELI alloy. EBM technique was used to fabricate Ti-6Al-4V ELI alloy blocks, which were cut into rectangular beam specimens with dimensions of 25 × 4 × 3 mm, such that electron beam orientation was either parallel (group A) or perpendicular (group B) to the long axis of the specimens. The specimens were subjected to cyclic fatigue (R = 0.1) in four-point flexure under ambient conditions using various stress amplitudes below the yield stress. The fatigue lifetime data were fit to an inverse power law-Weibull model to predict the peak stress corresponding to failure probabilities of 5 and 63% at 2M cycles (σ(max, 5%) and σ(max, 63%)). Groups A and B did not have significantly different Weibull modulus, m (p > 0.05). The specimens with parallel orientation showed significantly higher σ(max, 63%) (p ≤ 0.05), but there was no significant difference in the σ(max, 5%) (p > 0.05). Thus, it can be concluded that the fatigue resistance of the material was greatest when the electron beam orientation was perpendicular to the direction of crack propagation.
定制的单成分牙科植入物已使用电子束熔化（®）（EBM（®））制造，这是一种快速原型制造技术。我们的研究目的是确定电子束方向对 EBM Ti-6Al-4V ELI 合金疲劳强度的影响。使用 EBM 技术制造 Ti-6Al-4V ELI 合金块，将其切割成尺寸为 25×4×3mm 的矩形梁试件，使得电子束方向与试件的长轴平行（A 组）或垂直（B 组）。在环境条件下，通过四点弯曲对试件进行循环疲劳（R=0.1），施加低于屈服应力的各种应幅。将疲劳寿命数据拟合到逆幂律-Weibull 模型，以预测在 2M 循环时失效概率为 5%和 63%的峰值应力（σ（max，5%）和σ（max，63%））。A 组和 B 组的 Weibull 模数 m 没有显著差异（p>0.05）。具有平行取向的试件表现出显著更高的σ（max，63%）（p≤0.05），但σ（max，5%）（p>0.05）没有显著差异。因此，可以得出结论，当电子束方向垂直于裂纹扩展方向时，材料的疲劳强度最大。
