Pan American Materials Congress: Advanced Manufacturing: Poster Session
Sponsored by: Third Pan American Materials Congress Organizing Committee
Program Organizers: Sonia Brühl, UTN - National University of Technology; Ricardo Castro, University Of California, Davis; Dachamir Hotza, UFSC

Tuesday 5:30 PM
February 28, 2017
Room: Poster Area
Location: Marriott Marquis Hotel

PAN-12: Influence of Dendritic Morphology on the Strain Field of Dendritic Solidification Structures: Alejandro Moreno1; Mario Rosenberger2; Carlos Schvezov2; 1Facultad de Ciencias Exactas Químicas y Naturales - Universidad Nacional de Misiones; 2Instituto de Materiales de Misiones
    The effect of morphological parameters of solidified materials as: curvature of the dendrite tip, length of dendritic branches and grain size on the strain-stress fields was studied by numerical modeling. A two-dimensional model is performed to represent a dendritic grain geometry immersed on a matrix, this system is loaded with two different cases: simple tensile stresses and simple shear in the matrix. Several different plastic properties in an elastoplastic regime with the same stiffness are simulated. The results reflect a discontinuous distribution of stresses and strains in the microstructure at the interface, which shows that the stress and strain gradients increases with increasing curvature of the interface and decreases the length of the dendrite arm.

PAN-13: Microhardness Assessment of 316L Stainless Steel Fabricated by Laser Engineered Net Shaping: Katherine Acord1; Thale Smith2; Julie Schoenung1; 1University of California, Irvine; 2University of California, Davis
    Laser Engineered Net Shaping (LENS®) is a direct energy deposition processing technique that enables the formation of fine microstructures due to rapid solidification leading to improved strength and hardness; however, directional solidification results in locally varying thermal history that alters mechanical properties. The goals of this study are: to assess the role of feedstock powder characteristics on solidification structure and mechanical properties, and to determine the potential for inhomogeneous mechanical behavior due to the thermal effect of LENS® processing. Two 316L austenitic stainless steel powders produced by gas atomization (GA) and water atomization (WA) were utilized. Microindentation hardness testing was conducted using a geometric array in order to systematically evaluate the position-dependent mechanical properties. Findings elucidate the role of feedstock powder in controlling final properties of LENS® builds, while presenting a novel approach to thermal behavior assessment that accounts for the statistical significance of microhardness measurements.