Mingyu Liu , Jiang Wang , Tao Hu , Songzhe Xu , Sansan Shuai , Weidong Xuan , Shuo Yin , Chaoyue Chen , Zhongming Ren
{"title":"激光粉末床熔合和热等静压后处理ni3al基金属间合金的微观开裂、显微组织和力学性能","authors":"Mingyu Liu , Jiang Wang , Tao Hu , Songzhe Xu , Sansan Shuai , Weidong Xuan , Shuo Yin , Chaoyue Chen , Zhongming Ren","doi":"10.1016/j.apmate.2023.100152","DOIUrl":null,"url":null,"abstract":"<div><p>Ni<sub>3</sub>Al-based alloys are excellent candidates for the structural materials used for turbine engines due to their excellent high-temperature properties. This study aims at laser powder bed fusion and post-hot isostatic pressing (HIP) treatment of Ni<sub>3</sub>Al-based IC-221 M alloy with a high γ′ volume fraction. The as-built samples exhibits unavoidable solidification cracking and ductility dip cracking, and the laser parameter optimization can reduce the crack density to 1.34 mm/mm<sup>2</sup>. Transmission electron microscope (TEM) analysis reveals ultra-fine nanoscale γ′ phases in the as-built samples due to the high cooling rate during rapid solidification. After HIP treatment, a fully dense structure without cracking defects is achieved, which exhibits an equiaxed structure with grain size ∼120–180 μm and irregularly shaped γ′ precipitates ∼1–3 μm with a prominently high fraction of 86%. The room-temperature tensile test of as-built samples shows a high ultimate tensile strength (<em>σ</em><sub>UTS</sub>) of 1039.7 MPa and low fracture elongation of 6.4%. After HIP treatment, a significant improvement in ductility (15.7%) and a slight loss of strength (<em>σ</em><sub>UTS</sub> of 831.7 MPa) are obtained by eliminating the crack defects. Both the as-built and HIP samples exhibit retained high <em>σ</em><sub>UTS</sub> values of 589.8 MPa and 786.2 MPa, respectively, at 900 °C. The HIP samples exhibita slight decrease in ductility to ∼12.9%, indicating excellent high-temperature mechanical performance. Moreover, the abnormal increase in strength and decrease in ductility suggest the critical role of a high γ′ fraction in cracking formation. The intrinsic heat treatment during repeating thermal cycles can induce brittleness and trigger cracking initiation in the heat-affected zone with notable deteriorating ductility. The results indicate that the combination of LPBF and HIP can effectively reduce the crack density and enhance the mechanical properties of Ni<sub>3</sub>Al-based alloy, making it a promising material for high-temperature applications.</p></div>","PeriodicalId":7283,"journal":{"name":"Advanced Powder Materials","volume":null,"pages":null},"PeriodicalIF":0.0000,"publicationDate":"2023-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2772834X23000441/pdfft?md5=920cae6cedeb9df7a696f6200100a673&pid=1-s2.0-S2772834X23000441-main.pdf","citationCount":"0","resultStr":"{\"title\":\"Laser powder bed fusion of a Ni3Al-based intermetallic alloy with tailored microstructure and superior mechanical performance\",\"authors\":\"Mingyu Liu , Jiang Wang , Tao Hu , Songzhe Xu , Sansan Shuai , Weidong Xuan , Shuo Yin , Chaoyue Chen , Zhongming Ren\",\"doi\":\"10.1016/j.apmate.2023.100152\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>Ni<sub>3</sub>Al-based alloys are excellent candidates for the structural materials used for turbine engines due to their excellent high-temperature properties. This study aims at laser powder bed fusion and post-hot isostatic pressing (HIP) treatment of Ni<sub>3</sub>Al-based IC-221 M alloy with a high γ′ volume fraction. The as-built samples exhibits unavoidable solidification cracking and ductility dip cracking, and the laser parameter optimization can reduce the crack density to 1.34 mm/mm<sup>2</sup>. Transmission electron microscope (TEM) analysis reveals ultra-fine nanoscale γ′ phases in the as-built samples due to the high cooling rate during rapid solidification. After HIP treatment, a fully dense structure without cracking defects is achieved, which exhibits an equiaxed structure with grain size ∼120–180 μm and irregularly shaped γ′ precipitates ∼1–3 μm with a prominently high fraction of 86%. The room-temperature tensile test of as-built samples shows a high ultimate tensile strength (<em>σ</em><sub>UTS</sub>) of 1039.7 MPa and low fracture elongation of 6.4%. After HIP treatment, a significant improvement in ductility (15.7%) and a slight loss of strength (<em>σ</em><sub>UTS</sub> of 831.7 MPa) are obtained by eliminating the crack defects. Both the as-built and HIP samples exhibit retained high <em>σ</em><sub>UTS</sub> values of 589.8 MPa and 786.2 MPa, respectively, at 900 °C. The HIP samples exhibita slight decrease in ductility to ∼12.9%, indicating excellent high-temperature mechanical performance. Moreover, the abnormal increase in strength and decrease in ductility suggest the critical role of a high γ′ fraction in cracking formation. The intrinsic heat treatment during repeating thermal cycles can induce brittleness and trigger cracking initiation in the heat-affected zone with notable deteriorating ductility. The results indicate that the combination of LPBF and HIP can effectively reduce the crack density and enhance the mechanical properties of Ni<sub>3</sub>Al-based alloy, making it a promising material for high-temperature applications.</p></div>\",\"PeriodicalId\":7283,\"journal\":{\"name\":\"Advanced Powder Materials\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":0.0000,\"publicationDate\":\"2023-07-19\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://www.sciencedirect.com/science/article/pii/S2772834X23000441/pdfft?md5=920cae6cedeb9df7a696f6200100a673&pid=1-s2.0-S2772834X23000441-main.pdf\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Advanced Powder Materials\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S2772834X23000441\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Advanced Powder Materials","FirstCategoryId":"1085","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S2772834X23000441","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
Laser powder bed fusion of a Ni3Al-based intermetallic alloy with tailored microstructure and superior mechanical performance
Ni3Al-based alloys are excellent candidates for the structural materials used for turbine engines due to their excellent high-temperature properties. This study aims at laser powder bed fusion and post-hot isostatic pressing (HIP) treatment of Ni3Al-based IC-221 M alloy with a high γ′ volume fraction. The as-built samples exhibits unavoidable solidification cracking and ductility dip cracking, and the laser parameter optimization can reduce the crack density to 1.34 mm/mm2. Transmission electron microscope (TEM) analysis reveals ultra-fine nanoscale γ′ phases in the as-built samples due to the high cooling rate during rapid solidification. After HIP treatment, a fully dense structure without cracking defects is achieved, which exhibits an equiaxed structure with grain size ∼120–180 μm and irregularly shaped γ′ precipitates ∼1–3 μm with a prominently high fraction of 86%. The room-temperature tensile test of as-built samples shows a high ultimate tensile strength (σUTS) of 1039.7 MPa and low fracture elongation of 6.4%. After HIP treatment, a significant improvement in ductility (15.7%) and a slight loss of strength (σUTS of 831.7 MPa) are obtained by eliminating the crack defects. Both the as-built and HIP samples exhibit retained high σUTS values of 589.8 MPa and 786.2 MPa, respectively, at 900 °C. The HIP samples exhibita slight decrease in ductility to ∼12.9%, indicating excellent high-temperature mechanical performance. Moreover, the abnormal increase in strength and decrease in ductility suggest the critical role of a high γ′ fraction in cracking formation. The intrinsic heat treatment during repeating thermal cycles can induce brittleness and trigger cracking initiation in the heat-affected zone with notable deteriorating ductility. The results indicate that the combination of LPBF and HIP can effectively reduce the crack density and enhance the mechanical properties of Ni3Al-based alloy, making it a promising material for high-temperature applications.