Crystals (Mar 2020)
Microstructure and Mechanical Properties of Platinum Fiber Fabricated by Unidirectional Solidification
Abstract
The microstructure and mechanical properties of platinum (Pt) fibers fabricated by unidirectional solidification using the alloy-micro-pulling-down (A-μ-PD) method were investigated using a Universal Testing Machine and Electron Backscattered Diffraction (EBSD). The Pt fiber fabricated at a growth rate of 10 mm/min was composed of relatively large grains with <100> crystal orientation along the growth direction. The crystal orientation was consistent with the easy axis of the crystal growth on the face-centered-cubic (f.c.c.) structure. On the other hand, the adjacent grains of the Pt fiber fabricated at 50 mm/min were randomly oriented owing to a faster growth rate. In tensile tests, the Pt fibers fabricated by the A-μ-PD method indicated extremely different stress−strain curves compared to the commercial Pt wire. The maximum tensile stress of the Pt fiber reached ~100 MPa, and the Pt fiber ruptured after 58% nominal strain.
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