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DOE OSTI · 1562378

Tungsten Alloy Laser Track Cracking Analysis

Abstract

Tungsten exhibits many favorable properties such as a high melting point and high density. However, the hard and brittle nature of the material makes it difficult to work and machine. Tungsten can be alloyed with other elements to lower the material’s ductile-to-brittle transition temperature, thereby making it more ductile and workable at room temperature. While helpful for conventional manufacturing methods, the alloy poses a problem for additive manufacturing (AM) applications. The lower melting and vaporization point of the solute leads to increased vaporization. This in combination with intense localized heating and rapid cooling that occurs during AM processes creates residual stress in parts that contributes to cracking and increased porosity.

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Stackhouse, Nicole T.. 2019-08-30. Tungsten Alloy Laser Track Cracking Analysis. https://doi.org/10.2172/1562378

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36 MATERIALS SCIENCE↗