Hybrid Approach for Manufacturing Stiffened Structures Using Cold Spray Deposition
Open Access
- Author:
- Hennessey, Michael
- Graduate Program:
- Engineering Science and Mechanics (MS)
- Degree:
- Master of Science
- Document Type:
- Master Thesis
- Date of Defense:
- September 05, 2023
- Committee Members:
- Albert Segall, Program Head/Chair
Matt Lear, Thesis Advisor/Co-Advisor
Jeremy Michael Schreiber, Committee Member
Timothy John Eden, Committee Member - Keywords:
- Cold Spray
Aluminum 6061
Additive Manufacturing - Abstract:
- Recent advancements in the consistency and reliability of cold spray (CS) technology have increased interest in using cold spray as an additive manufacturing (AM) method. The challenge in employing this technology, similar to any additive manufacturing method, is the ability to guarantee isotropic mechanical properties of the AM part that are comparable to wrought material. The goal of this research effort is to prove parts made with a hybrid approach using 6061 powder and 6061-T6 wrought aluminum substrate performs comparably to a part machined entirely from wrought aluminum (6061-T6). CS parameters were verified through adhesion testing, interfacial imaging, coating pass thickness measurements, and tensile testing of 100% cold sprayed dogbone specimens. T-channel specimens were manufactured using CS deposition, representing a plate with a rib to stiffen the structure. Two types of T-channels, CS coating and wrought aluminum, were tested in four-point bending. Strain, force, and displacement data were collected. Specimens were sectioned and imaged with optical microscopy and scanning electron microscopy, before and after testing to study the effect of a bending load on coating quality. A finite element model was built to compare with empirical data collected from four-point bend testing. Johnson-Cook plasticity was used to model the plastic behavior of the cold sprayed parts. Johnson-Cook parameters were tuned using tensile test data for the 6061 powder. Tensile data and four-point bending results indicated that cold sprayed specimens had strength and stiffness comparable to the wrought specimens with an expected reduction in ductility that is inherent in cold sprayed coatings. Future work should look to apply the hybrid approach for different geometries and investigate the effects of fatigue loading on the coating interface.