Very high cycle fatigue and fatigue crack propagation behavior of selective laser melted AlSi12 alloy
Very high cycle fatigue and fatigue crack propagation behavior of selective laser melted AlSi12 alloy
复制标题
DOI：
10.1016/j.ijfatigue.2016.06.003
复制
发表时间：
2017-01-01
影响因子：
6
通讯作者：
Walther, Frank
中科院分区：
文献类型：
--
作者：
Siddique, Shafaqat;Imran, Muhammad;Walther, Frank
选择性激光熔化是近年来发展起来的一种成熟的增材制造工艺。然而，重点仍然是可加工性、设计考虑和静态或准静态机械性能。对于功能性部件的工艺应用，要求工艺部件在循环应用中也表现良好。加工参数对最终零件参数和相应的疲劳行为的影响尚未得到解决。本研究探讨了基板加热和加工后应力消除对AlSi12合金零件性能的影响，如工艺激发缺陷，这对疲劳加载至关重要。对高周疲劳和疲劳裂纹扩展进行了研究。为了了解疲劳现象，还对材料的基本性能进行了表征。结果表明，这些参数对材料缺陷和微观组织都有影响。底板加热改善了相应的疲劳裂纹扩展行为，改变了疲劳裂纹的起裂机制。通过基片加热相对降低热梯度，减少材料缺陷引起的疲劳裂纹萌生，有助于提高疲劳可靠性。(C) 2016 Elsevier Ltd.版权所有。
Selective laser melting is a maturing additive manufacturing process which has been studied in the recent years for processing different alloys. The focus, however, remained on the processibility, design considerations and static or quasistatic mechanical properties. For the application of the process for functional components, it is required that the process parts perform well in cyclic applications as well. The influence of processing parameters on the resulting part parameters and the corresponding fatigue behavior remains unaddressed. This study investigates the influence of base plate heating and post process stress-relief on part properties like process-incited defects, which are critical for fatigue loading, for AlSi12 alloy. Investigations have been made for very high cycle fatigue as well as fatigue crack growth. To understand the fatigue phenomenon, characterization of basic material properties is also carried out. Results show that the material defects as well as microstructure is influenced by these parameters. The corresponding fatigue and crack growth behavior is improved by base plate heating which changes the fatigue crack initiation mechanisms as well. Relatively reduced thermal gradients by base plate heating helps improving the fatigue reliability by reducing the fatigue crack initiation from material defects. (C) 2016 Elsevier Ltd. All rights reserved.