Microstructural Analysis of Cadmium Whiskers on Long-Term-Used Hardware

Abstract

A survey of cadmium plated field return hardware showed ubiquitous cadmium whisker growth. The most worn and debris-covered hardware showed the densest whisker growth. Whiskers were often found growing in agglomerates of nodules and whiskers. The hardware was rinsed with alcohol to transfer whiskers and debris from the hardware to a flat stub. Fifty whiskers were studied individually by scanning electron microscopy (SEM), including energy dispersive spectroscopy (EDS) and electron backscatter diffraction (EBSD). Most of the whiskers were single crystal, though three were found to contain grain boundaries at kinks. The whiskers ranged from 5 to 600 lm in length and 80 pct showed a <1 2 1 0> type growth direction. This growth direction facilitates the development of low energy side faces of the whisker, (0001) and {1010}.