Effect of heat treatment on microstructure and tensile properties of Inconel 718 alloy prepared by selective laser melting

doi:10.13251/j.issn.0254-6051.2021.10.021

Abstract

Abstract: Inconel 718 alloy was prepared by selective laser melting (SLM) process. The solution treatment at 1050 ℃ for 1 h, solution treatment at 1050 ℃ for 1 h and aging treatment at 720 ℃ for 8 h and 620 ℃ for 8 h were respectively applied on the SLM processed alloy. The effect of heat treatment process on the microstructure and mechanical properties of the SLM-Inconel 718 alloy were studied by combining with microstructure analysis, tensile properties analysis and fracture characteristics analysis. The results show that the density of dislocations is significantly reduced associated with Laves phase dissolving after solid solution treatment. Hence the strength-plasticity matching of the alloy is better than that of the as-SLM state. After aging, γ′ and γ″ strengthening phases precipitate out, which greatly increase the strength of the alloy while retaining a certain plasticity.

Key words: selective laser melting, Inconel 718 alloy, heat treatment, microstructure, tensile properties

CLC Number:

TG142.1

Zeng Qiang, Wu Ying, Xiao Huijin, Zhu Shaowei. Effect of heat treatment on microstructure and tensile properties of Inconel 718 alloy prepared by selective laser melting[J]. Heat Treatment of Metals, 2021, 46(10): 122-126.

References

[1]Liverani E, Fortunato A, Leardini A, et al. Fabrication of Co-Cr-Mo endoprosthetic ankle devices by means of selective laser melting (SLM)[J]. Materials and Design, 2016, 106: 60-68.
[2]朱文志, 党明珠, 田健, 等. 激光能量密度对激光选区熔化Cu-Al-Ni-Ti合金相对密度, 微观组织和力学性能的影响[J]. 机械工程学报, 2020, 56(15): 53-64.
Zhu Wenzhi, Dang Mingzhu, Tian Jian, et al. Effect of laser energy density on relative density, microstructure and mechanical properties of Cu-Al-Ni-Ti alloy fabricated by selective laser melting[J]. Journal of Mechanical Engineering, 2020, 56(15): 53-64.
[3]曾强, 吴颖, 肖辉进, 等. 油气工程用Inconel 718合金激光焊接头的氢脆行为[J]. 金属热处理, 2020, 45(8): 50-55.
Zeng Qiang, Wu Ying, Xiao Huijin, et al. Hydrogen embrittlement behavior of oilfield-grade Inconel 718 alloy laser welded joint[J]. Heat Treatment of Metals, 2020, 45(8): 50-55.
[4]孙艳容, 王杰, 杨锦, 等. 热处理制度对IN718变形合金组织和性能的影响[J]. 金属热处理, 2018, 43(12): 152-159.
Sun Yanrong, Wang Jie, Yang Jin, et al. Effect of heat treatment on microstructure and mechanical properties of IN718 deformed alloy[J]. Heat Treatment of Metals, 2018, 43(12): 152-159.
[5]Hosseini E, Popovich V A. A review of mechanical properties of additively manufactured Inconel 718[J]. Additive Manufacturing, 2019, 30: 100877.
[6]Chen Y, Guo Y B, Xu M J, et al. Study on the element segregation and Laves phase formation in the laser metal deposited IN718 superalloy by flat top laser and gaussian distribution laser[J]. Materials Science and Engineering, 2019, 754: 339-347.
[7]Zhang B C, Xiu M Z, Tan Y T, et al. Pitting corrosion of SLM Inconel 718 sample under surface and heat treatments[J]. Applied Surface Science, 2019, 490: 556-567.
[8]Zhu Z G, Nguyen Q B, Ng F L, et al. Hierarchical microstructure and strengthening mechanisms of a CoCrFeNiMn high entropy alloy additively manufactured by selective laser melting[J]. Scripta Materialia, 2018, 154: 20-42.
[9]Li Z, He B, Guo Q. Strengthening and hardening mechanisms of additively manufactured stainless steels: The role of cell sizes[J]. Scripta Materialia, 2020, 177: 17-21.
[10]Gallmeyer T G, Moorthy S, Kappes B B, et al. Knowledge of process-structure-property relationships to engineer better heat treatments for laser powder bed fusion additive manufactured Inconel 718[J]. Additive Manufacturing, 2020, 31: 100977.
[11]Schneider J, Lund B, Fullen M. Effect of heat treatment variations on the mechanical properties of Inconel 718 selective laser melted specimens[J]. Additive Manufacturing, 2018, 21: 248-254.
[12]Cao G H, Sun T Y, Wang C H, et al. Investigations of γ′, γ″ and δ precipitates in heat-treated Inconel 718 alloy fabricated by selective laser melting[J]. Materials Characterization, 2018, 136: 398-406.
[13]彭子超, 谢发勤, 张军, 等. 过冷度对IN718高温合金组织演化影响[J]. 稀有金属材料与工程, 2013, 42(10): 1988-1992.
Peng Zichao, Xie Faqin, Zhang Jun, et al. Effect of undercooling on microstructure evolution in IN718 superalloy[J]. Rare Metal Materials and Engineering, 2013, 42(10): 1988-1992.
[14]郑欣, 师玉英, 陈玉宝. 时效处理对GH4169合金组织和性能的影响[J]. 金属热处理, 2018, 43(6): 162-165.
Zheng Xin, Shi Yuying, Chen Yubao. Efect of aging on the microstructure and properties of GH4169 alloy[J]. Heat Treatment of Metals, 2018, 43(6): 162-165.
[15]Herzog D, Seyda V, Wycisk E, et al. Additive manufacturing of metals[J]. Acta Materialia, 2016, 117: 371-392.
[16]Zhong Y, Liu L, Wikman S, et al. Intragranular cellular segregation network structure strengthening 316L stainless steel prepared by selective laser melting[J]. Journal of Nuclear Materials, 2016, 470: 170-178.
[17]Luo S C, Huang W P, Yang H H, et al. Microstructural evolution and corrosion behaviors of Inconel 718 alloy produced by selective laser melting following different heat treatments[J]. Additive Manufacturing, 2019, 30: 100875.
[18]宋宜四, 高万夫, 王超, 等. 热处理工艺对Inconel 718合金组织, 力学性能及耐蚀性能的影响[J]. 材料工程, 2012(6): 37-42.
Song Yisi, Gao Wanfu, Wang Chao, et al. Effect of heat treatment technology on microstructure, mechanical property and corrosion resistance of nickel-base alloy Inconel 718[J]. Materials Engineering, 2012(6): 37-42.