Identification of whisker grain in Sn coatings by analyzing crystallographic micro-texture using electron back-scatter diffraction

Jagtap, Piyush and Chakraborty, Aritra and Eisenlohr, Philip and Kumar, Praveen (2017) Identification of whisker grain in Sn coatings by analyzing crystallographic micro-texture using electron back-scatter diffraction. In: ACTA MATERIALIA, 134 . pp. 346-359.

PDF Act_Mat_134_346_2017.pdf - Published Version Restricted to Registered users only Download (6MB) | Request a copy

Abstract

Here, we attempt to understand the age-old question of ``where do whiskers in Sn coatings grow?'' by performing grain orientation mapping in conjunction with a simple analysis of the stress field in the vicinity of a whisker grain. Electron back-scatter diffraction (EBSD) was used for orientation mapping of Sn grains in a 4 gm thick Sn coating deposited on brass. It was observed that whiskers consistently grew from low-index grains with (100) or near-(100) orientations that were surrounded by grains with similar orientations, which were then partially surrounded by grains with high-index planes, such as (211), (321) and (420). Strong elastic anisotropy and overall a high fraction of high-angle grain boundaries were also consistently observed in the vicinity of whiskers. In addition, a full-field three-dimensional crystal elasticity simulations were performed using the EBSD orientation maps to analyze local stress variations in the vicinity of the whisker grain. These simulations indicate the presence of a high compressive hydrostatic stress around the whisker grain, which could then possibly create conducive conditions for whisker growth observed experimentally. (C) 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Item Type:	Journal Article
Publication:	ACTA MATERIALIA
Additional Information:	Copy right for this article belongs to the PERGAMON-ELSEVIER SCIENCE LTD, THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND
Department/Centre:	Division of Mechanical Sciences > Materials Engineering (formerly Metallurgy)
Date Deposited:	01 Sep 2017 09:31
Last Modified:	01 Sep 2017 09:31
URI:	http://eprints.iisc.ac.in/id/eprint/57717

Actions (login required)

View Item