Process structure linkages for channel–die compressed mg alloy 08-10-2014

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Steps to obtain 2-point statistics from EBSD data using Binning Team Members Akash Gupta , Dipen Patel Georgia Institute of Technology, Atlanta, US

Transcript of Process structure linkages for channel–die compressed mg alloy 08-10-2014

1. Steps to obtain 2-point statistics fromEBSD data using BinningTeam MembersAkash Gupta , Dipen PatelGeorgia Institute of Technology, Atlanta, US 2. Step 1: Extracting orientations from EBSD data 1 microstructure is selected at processing conditions: T=3000C, =73%, =0.01 OIM analysis software is used to extract 2-D pixel data containing crystal orientations (1,, 2) from .oim files Size of microstructure = (200 x 200) m , (1000 x 1000) pixels Microstructure contains large number of grains with unique orientation leading to large number of local states ~ 105 th microstructure (500 x 500) pixels was selected for further steps 3. Step 2: Finding equivalent orientation in FZ 12 lattice symmetry operations associated with hexagonal crystal lattice leads to 12equivalent orientationsRef: Microstructure-sensitive Design forPerformance Optimization (2013), Authors: Brent L.Adams, Surya Kalidindi, David T. Fullwood 4. Step 3: Binning of Fundamental Zone (FZ) Number of local states in microstructure can be governed here For this study we fixed number of local states (bins) to be 60 (5x4x3) 5. Step 4: Assigning bins to grains in microstructure Based on orientations, each grain is assigned to one of the 60 bins (local states) in fundamental zone Number of local states reduced from ~ 105 to 60 6. Step 5: 2-point statistics Local state with highest frequency i.e. 54 is shown in white color in binary image Auto-correlation for local state 54 7. Way Forward and Challenges Compute all independent cross-correlations Generate statistics for rest of the structures and do PCA Challenges handling big data files and generating good images with 1000 x 1000 pixels Repeating above mentioned process for rest of the structure files will require huge computational time