Sandell Viktor, Hansson Thomas, Roychowdhury Sushovan, Månsson Tomas, Delin Mats, Åkerfeldt Pia, Antti Marta-Lena
Division of Materials Science, Luleå University of Technology, 731 87 Luleå, Sweden.
Division 9654: Materials Engineering, GKN Aerospace, 461 38 Trollhättan, Sweden.
Materials (Basel). 2021 Jan 30;14(3):640. doi: 10.3390/ma14030640.
Electron beam melting is a powder bed fusion (PBF) additive manufacturing (AM) method for metals offering opportunities for the reduction of material waste and freedom of design, but unfortunately also suffering from material defects from production. The stochastic nature of defect formation leads to a scatter in the fatigue performance of the material, preventing wider use of this production method for fatigue critical components. In this work, fatigue test data from electron beam melted Ti-6Al-4V specimens machined from as-built material are compared to deterministic fatigue crack growth calculations and probabilistically modeled fatigue life. X-ray computed tomography (XCT) data evaluated using extreme value statistics are used as the model input. Results show that the probabilistic model is able to provide a good conservative life estimate, as well as accurate predictive scatter bands. It is also shown that the use of XCT-data as the model input is feasible, requiring little investigated material volume for model calibration.
电子束熔炼是一种用于金属的粉末床熔融（PBF）增材制造（AM）方法，它为减少材料浪费和设计自由提供了机会，但不幸的是，生产过程中也存在材料缺陷。缺陷形成的随机性导致材料疲劳性能的分散，阻碍了这种生产方法在疲劳关键部件中的更广泛应用。在这项工作中，将由增材制造材料加工而成的电子束熔炼Ti-6Al-4V试样的疲劳试验数据与确定性疲劳裂纹扩展计算和概率建模的疲劳寿命进行了比较。使用极值统计评估的X射线计算机断层扫描（XCT）数据用作模型输入。结果表明，概率模型能够提供良好的保守寿命估计以及准确的预测散射带。还表明，使用XCT数据作为模型输入是可行的，模型校准所需的研究材料体积很少。
