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Materials Science in Additive Manufacturing High-performance materials in AM

Figure 9. Synthesis of HSPEEK and summary of the experimental procedure .
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manufacture of polyimide materials using AM technology In the field of metals, the study of HEAs and their
are being innovated to increase thermal stability and may processing methods is currently the focus of research.
be used in special applications with higher operating This unique type of alloy is gradually becoming the most
temperatures . dominant material in future, and its unique value compels
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Blending polyimide-based composites with CNT is researchers to devote greater attention to it; therefore,
a popular research topic, and researchers are exploring this section will focus on this unique metal concept, the
the processing of polyimide-CNT composites in current status of development and application of HEAs,
MEX technology after overcoming the problems of the composites involved, and the integration of HEAs
inhomogeneous mixing associated with conventional with AM technology. This section summarizes the work of
sonication and other methods . After optimizing researchers in recent years and analyzes future directions
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the process parameters during the process and the of research and development.
filling level of CNT, finished complex structures with 4.1. Concept and current development
exceptional electrical and mechanical properties and
anti-electromagnetic shielding were successfully prepared The concept of alloys has been around for a long time
by MEX technology, offering new possibilities for the and since the discovery of metal materials, the process
application of this new composite material in cutting-edge and method of adding different elements to pure metals
fields such as aerospace . to improve metal properties have been explored by
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generations of researchers.
In the future, research into improving the accuracy
and stability of polyimide materials in AM technology The concept of HEAs was first introduced by Yeh
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will continue, and this important polymer material and its et al. in 2004 , and its original definition requires that
complexes will play an even more significant role in future it comprises at least five principal elements and that the
developments. atomic concentration of each principal element is between
5% and 35%. Subsequent researchers have expanded the
4. High entropy alloys and its composites concept of HEAs to also include alloys containing three
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for additive manufacturing or four principal elements. Although the concept of HEAs
has been promulgated for less than two decades, this
It has always been a research focus to investigate new concept has already disrupted the traditional framework of
alloys, which are commonly employed in AM technology alloy research and has grown into a major research hotspot
and are essential materials for human society. There is in metallic materials science.
an increasing demand for metal components with high-
performance and ultra-complex structures, but traditional The “entropy” in the “high entropy alloy” refers to
manufacturing techniques are limited by their metal the constitutive entropy of the alloy and according to
processing capabilities. Thus, this highlights the need for Equation I, an increase in entropy at high temperatures will
rapid commercialization of new alloys and innovation of result in a significant decrease in Gibbs free energy, which, in
manufacturing technologies. turn, will show the stability of the phases in the material .
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Volume 2 Issue 3 (2023) 9 https://doi.org/10.36922/msam.1587