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Title: Effects of Scanning Strategy on Residual Stress Formation in Additively Manufactured SS 17-4 PH
Parts fabricated via directed energy additive manufacturing (AM) can experience very high, localized temperature gradients during manufacture. These temperature gradients are conducive to the formation of a complex residual stress field within such parts. In the study, a thermo-mechanical model is employed for predicting the temperature distribution and residual stress in Ti-6Al-4V parts fabricated using laserpowder bed fusion (L-PBF). The result is utilized for determining a relationship between local part temperature gradients with generated residual stress. Using this numerical model, the effects of scan patterns are investigated.
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28th International Solid Freeform Fabrication Symposium - An Additive Manufacturing Conference
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National Science Foundation
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    Distortion arises during machining of metallic parts from two main mechanisms: 1) release of bulk residual stress (BRS) in the pre-form, and 2) permanent deformation induced by cut tools. Interaction between these mechanisms is unexplored.


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