Sun, Z., Soh, V., Lee, C., Wuu, D., Lau, D., Wei, S., Ng, C. K., Sing, S. L., Tan, D., Wang, P. (2024). Effects of carbon content on precipitate evolution and crack susceptibility in additively manufactured IN738LC. Materials Science in Additive Manufacturing, 3(1), 2264. https://doi.org/10.36922/msam.2264
Abstract:
Hot cracking is a major bottleneck preventing the additive manufacturing community from adopting precipitation-strengthened nickel-base superalloys, such as the IN738LC. Prior literature demonstrates the beneficial outcome of increasing the carbon content within IN738LC to alleviate its hot cracking problem. However, the effect of carbon content on the gamma prime precipitation and grain recrystallization was not fully addressed. Here, we fabricated five sample sets of IN738LC with different carbon contents and subjected these samples to two separate heat treatment processes. The precipitate and grain evolution were monitored under the backscattered electron imaging and electron backscattered diffraction studies. While the carbon addition could assist in addressing the hot cracking problem, horizontal delamination cracks were detected during the fabrication of large samples when the overall carbon content was above 0.4 wt.%, highlighting the need for care when introducing carbon for the purpose of resolving hot cracking.
License type:
Attribution 4.0 International (CC BY 4.0)
Funding Info:
This research / project is supported by the Agency for Science, Technology and Research - Career Development Fund
Grant Reference no. : C222812017
This research / project is supported by the Agency for Science, Technology and Research - Young Individual Research Grant
Grant Reference no. : M22K3c0096
This research / project is supported by the Agency for Science, Technology and Research - Individual Research Grant
Grant Reference no. : A20E7c0109