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Engineering Science in
Additive Manufacturing HIP temperature effects on LPBF Hastelloy X

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Figure 12. The fracture surface of Hastelloy X tensile specimens failed at high temperatures. Results of (A and A ) HIP1100, (B and B ) HIP1180, and
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(C and C ) HIP1210 specimens. Scale bars: (A -D ) 100 μm; (A -D ) 20 μm, magnifications: (A -D ) ×500; (A -D ) ×2,500.
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Abbreviation: HIP: Hot isostatic pressing.
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Figure 13. Schematic diagram of high-temperature fracture mechanism. (A and A ) HIP1100, (B and B ) HIP1180, and (C and C ) HIP1210 specimen.
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Abbreviation: HIP: Hot isostatic pressing.
the carbides along the grain boundaries significantly In contrast to the strengthening effect during room
coarsened with uneven carbide size after the 900°C tensile temperature tensile testing, the weakening of grain
test, while the carbides within the grains remained finely boundaries occurred during the high temperature
dispersed. In contrast, due to the continuous carbide tensile test, contributing to differing crack propagation
distribution along the grain boundaries before deformation, mechanisms in different HIP specimens. During the high-
the carbides in the HIP1180 and HIP1210 specimens temperature tensile deformation, dislocation pile-up at
precipitated predominantly near the grain boundaries, grain boundaries was alleviated under the combined effect
as shown in Figure 13B , B , C , and C . Moreover, only a of high temperature and tensile stress, contributing to the
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small number of carbides were observed to be dispersed reduced strength of the grain boundaries. Therefore, grain
within the grains. boundary sliding and migration became more likely, with
Volume 1 Issue 2 (2025) 11 doi: 10.36922/ESAM025240015