Dr. Gockel’s research interests span several aspects of additive manufacturing: the effect of defects, transient process behavior, in-process sensing, residual stresses, and graded alloy manufacturing. Our work has developed a statistical understanding of the relationship between processing parameters to material variations such as surface roughness and porosity and how these features relate to fatigue failure mechanisms. The generation of non-random defects is largely driven by transient process behavior, which we are predicting through simple experiments and modeling. In-situ detection of the life-limiting defects is investigated using innovative monitoring techniques, such as visible spectroscopy. Extreme thermal cycling and changes in local geometry result in residual stresses in the material that we investigate through multiple material analysis methods and modeling. Understanding of next generation techniques, such as graded alloy manufacturing, is undertaken using experimental material characterization methods and modeling of concerns such as interface residual stress.
Prior to joining Wright State University she was a lead engineer in research and development for GE Aviation’s Additive Development Center where she specialized in the development of process parameters for new materials to satisfy design and mechanical property requirements and enable aerospace applications. She earned her Ph.D. in Mechanical Engineering in 2014 from Carnegie Mellon University where her research provided a foundational method in the relation of processing parameters and melt pool geometry to microstructure. She received her bachelor’s degree in 2009 and master’s degree in 2010 from Wright State University where her research focused on analytical models to determine melt pool behavior in additive manufacturing. During her undergraduate study, she was a student researcher in the Materials Directorate at the Air Force Research Laboratory where she performed characterization tests for ceramic fibers and fiber coatings for ceramic matrix composites.
- Sheridan, L., J. Gockel, O. Scott-Emuakpor, “Stress-Defect-Life Interactions of Fatigued Additively Manufactured Alloy 718,” International Journal of Fatigue, Accepted for Publication, 10/2020.
- Raplee, J., J. Gockel, F. List III , K. Carver, S. Foster, T. McFalls, V. Paquit, R. Rao, D. W. Gandy, and S.S. Babu. “Towards Process Consistency and In-situ Evaluation of Porosity during Laser Powder Bed Additive Manufacturing.” Science and Technology of Welding and Joining, 25:8, 679-689, 2020.
- Sheridan, L., J. Gockel, and O. Scott-Emuakpor, “Rapid Initiation and Growth Life Characterization of Additively Manufactured Alloy 718 Through Compliance Monitoring.” Extreme Mechanics Letters, 40, 2020.
- Evans, R., J. Walker, J. Middendorf, and J. Gockel, “Modeling and Monitoring of the Effect of Scan Strategy on Microstructure in Additive Manufacturing.” Metallurgical and Materials Transactions A, 51, 4123–4129, 2020.
- Sheridan, L., B. Whip, and J. Gockel, “Primary Processing Parameter Effects on Defects and Fatigue in Alloy 718,” in Structural Integrity of Additive Manufactured Parts, ed. N. Shamsaei, S. Daniewicz, N. Hrabe, S. Beretta, J. Waller, and M. Seifi (West Conshohocken, PA: ASTM International, 2020), 450–464.
- Eidt W., E.P. Tatman, J. Kastner, J. McCarther, S. Gunther, J. Gockel, “Surface Roughness Characterization in Laser Powder Bed Fusion Additive Manufacturing”, 30th Annual International Solid Freeform Fabrication Symposium Proceedings. Austin, TX, 2019.
- Sheridan, L., J. Gockel, and O. Scott-Emuakpor, “Primary processing parameters and the production of porosity in additively manufactured alloy 718,” Journal of Engineering Materials and Performance, 28 (9), 5387-5397, 2019.
- Obidigbo, C., EP. Tatman, and J. Gockel, “Processing Parameter and Transient Effects on Melt Pool Geometry in Additive Manufacturing of Invar 36,” The International Journal of Advanced Manufacturing Technology, 104 (5-8), 3139-3146, 2019.
- Whip, B., L. Sheridan, and J. Gockel, “The Effect of Primary Processing Parameters on Surface Roughness in Laser Powder Bed Additive Manufacturing.” The International Journal of Advanced Manufacturing Technology, 103, 4411-4422, 2019.
- Levkulich, N., S. L. Semiatin, J. Gockel, J. Middendorf, A. DeWald, N. Klingbeil, “The Effect of Process Parameters on Residual Stress Evolution and Distortion in Laser Powder Bed Fusion of Ti-6Al-4V,” Additive Manufacturing, 28, 475-484, 2019.
- J. Gockel, L. Sheridan, B. Koerper, and B. Whip, “The Influence of Additive Manufacturing Processing Parameters on Surface Roughness and Fatigue Life.” International Journal of Fatigue, 124, 380-388, 2019.
- Sheridan, L., O. Scott-Emuakpor, T. George, T, and J. Gockel, “Relating Porosity to Fatigue Failure in Additively Manufactured Alloy 718.” Materials Science and Engineering: A, 170-176, 2018.
- Gockel, J., Sheridan, L., Narra, S. P., Klingbeil, N. W., and Beuth, J. “Trends in Solidification Grain Size and Morphology for Additive Manufacturing of Ti-6Al-4V.” JOM, 69 (12), 2706-2710, 2017.
- Gockel, J., N. Klingbeil, and S. Bontha. “A Closed-Form Solution for the Effect of Free Edges on Melt Pool Geometry and Solidification Microstructure in Additive Manufacturing of Thin Wall Geometries” Metallurgical and Materials Transactions B 47 (2), 1400-1408, 2016.
- Gockel, J., J. Fox, J. Beuth and R. Hafley. “Integrated melt pool and microstructure control for Ti-6Al-4V thin wall additive manufacturing.” Materials Science and Technology, vol. 31, pp. 912-916, 2015.
- Gockel, J., J. Beuth, K. Taminger. “Integrated Control of Solidification Microstructure and Melt Pool Dimensions in Electron Beam Wire Feed Additive Manufacturing.” Additive Manufacturing, vol. 1, pp. 119-126, 2014.
- Hay, R. S., E. E. Boakye, P. Mogilevsky, G. E. Fair, T. A. Parthasarathy, J. E. Davis. “Transformation Plasticity in (GdxDy1-x)PO4 Fiber Coatings During Fiber Pushout.” Journal of the American Ceramic Society, vol. 96, pp. 1586-1595, 2013.