选区激光熔化成形GH3536合金显微组织和力学性能研究

选区激光熔化成形GH3536合金显微组织和力学性能研究
朱轶凡，吕俊霞*，王 昊，刘兴迪，程晓鹏
（北京工业大学 材料科学与工程学院，北京 100124）

摘  要   研究了选区激光熔化(selective laser melting, SLM)成形GH3536合金沉积态的显微组织和力学性能。对室温下不同方向的SLM GH3536合金试样进行原位拉伸试验，对晶粒取向的演化进行探究并分析了力学性能各向异性的原因。结果表明，SLM GH3536合金的晶粒为沿成形高度方向生长的柱状晶，存在<101>方向的择优取向并在亚晶结构中存在高密度的位错。合金强化机制的定量分析表明，试样的屈服强度各向异性主要归因于晶界强化和位错强化的差异。沿拉伸方向Z(建造方向)试样中大量晶粒由<101>向<114>的转动提高了协调变形能力，H(垂直建造方向)试样中只有轻微变形织构的出现，Z试样比H试样具有更优秀的延展性。
关键词  选区激光熔化；GH3536合金；力学性能各向异性；原位拉伸
中图分类号：TB31; TG132. 3+ 2; TG14; V19; TG115. 21+ 5. 3
文献标识码：A  doi:10.3969/j.issn.1000-6281.2024.04.003
 

Investigation of microstructure and properties of GH3536 alloy fabricated by selective laser melting
ZHU Yifan, LÜ Junxia*, WANG Hao, LIU Xingdi, CHENG Xiaopeng
(College of Materials Science and Engineering, Beijing University of Technology, Beijing 100124, China)

Abstract  This study investigated the microstructure and mechanical properties of the GH3536 alloy produced via Selective Laser Melting (SLM). In-situ tensile tests were conducted at room temperature on SLM GH3536 alloy specimens with different orientations to analyze the evolution of grain orientation and determine the reasons for the anisotropy of mechanical properties. The results indicated that the grains of SLM GH3536 alloy were columnar crystals growing in the building direction, with a preferential orientation in the <101> direction and a high density of dislocations within the sub-crystalline structure. Quantitative analyses of the alloy’s strengthening mechanisms showed that the yield strength anisotropy of the specimens is primarily due to differences in grain boundary strengthening and dislocation strengthening. The Z-direction (building direction) specimen exhibited a larger number of grains rotating from <101> to <114> along the tensile axis, resulting in improved coordinated deformation and higher ductility compared to the H-direction (vertical building direction) specimen. In the H specimen, only slight deformation occured.
Keywords   selective laser melting; GH3536 alloy; mechanical properties anisotropy; in-situ tensile
 

[1] ZHANG W, LIU F, LIU F, et al. Microstructural evolution and cracking behavior of Hastelloy X superalloy fabricated by laser directed energy deposition [J].  Journal of Alloys and Compounds, 2022, 905: 164179.
[2] 李威霖, 丁青青, 吴中天, 等. 时效工艺对Inconel 718合金显微结构和力学性能的影响 [J]. 电子显微学报, 2023, 42(5): 565-573.
[3] KONG D, NI X, DONG C, et al. Anisotropic response in mechanical and corrosion properties of Hastelloy X fabricated by selective laser melting[J]. Construction and Building Materials, 2019, 221: 720-729.
[4] SANCHEZ-MATA O, WANG X L, MUñIZ-LERMA J A, et al. Dependence of mechanical properties on crystallographic orientation in nickel-based superalloy Hastelloy X fabricated by laser powder bed fusion [J]. Journal of Alloys and Compounds, 2021, 865: 158868.
[5] KUNZE K, ETTER T, GRäSSLIN J, et al. Texture, anisotropy in microstructure and mechanical properties of IN738LC alloy processed by selective laser melting (SLM) [J]. Materials Science and Engineering: A, 2015, 620: 213-222.
[6] 宗学文, 高倩, 周宏志, 等.  体激光能量密度对选区激光熔化316L不锈钢各向异性的影响 [J]. 中国激光, 2019, 46(5): 344-350.
[7] 王晋, 马晋遥, 唐亮, 等. 扫描电镜纳米分辨高温力学原位仪器研制进展 [J]. 电子显微学报, 2022, 41(6): 645-653.
[8] 谢强, 吕俊霞, 周建力, 等.  直接激光沉积Ti6Al4V合金疲劳裂纹萌生原位研究 [J]. 电子显微学报,  2022, 41(5): 542-549.
[9] 何文玲, 吕俊霞, 程晓鹏, 等.  镍基单晶高温合金孔洞区域蠕变行为原位SEM研究 [J]. 电子显微学报, 2022, 41(5): 507-514.
[10] 管浩, 佟翔宇, 谢强, 等.  几种合金拉伸变形组织的原位观察 [J]. 电子显微学报, 2021, 40(6): 650-657.
[11] HAN Y D, ZHANG Y K, JING H Y, et al. Selective laser melting of low-content graphene nanoplatelets reinforced 316L austenitic stainless steel matrix: Strength enhancement without affecting ductility [J]. Additive Manufacturing, 2020, 34: 101381.
[12] ROTH H A, DAVIS C L, THOMSON R C. Modeling solid solution strengthening in nickel alloys[J]. Metallurgical and Materials Transactions A, 1997, 28: 1329-1335.
[13] MA K K, WEN H M, HU T, et al. Mechanical behavior and strengthening mechanisms in ultrafine grain precipitation-strengthened aluminum alloy [J].  Acta Materialia, 2014, 62: 141-155.
[14] HANSEN N. Hall–Petch relation and boundary strengthening[J]. Scripta Materialia, 2004, 51(8): 801-806.
[15] JIANG S N, SHEN J J, NAGASAKA T, et al. Interfacial characterization of dissimilar-metals bonding between vanadium alloy and Hastelloy X alloy by explosive welding [J]. J Nucl Mater, 2020, 539: 152322.
[16] SMITH T R, SUGAR J D, MARCHI C S, et al. Strengthening mechanisms in directed energy deposited austenitic stainless steel [J]. Acta Materialia, 2019, 164: 728-740.
[17] SUI S, TAN H, CHEN J, et al. The influence of Laves phases on the room temperature tensile properties of Inconel 718 fabricated by powder feeding laser additive manufacturing [J]. Acta Materialia, 2019, 164: 413-427.
[18] ESMAEILIZADEH E, KESHAVARZKERMANI A, ALI U, et al. Customizing mechanical properties of additively manufactured Hastelloy X parts by adjusting laser scanning speed [J]. Journal of Alloys and Compounds, 2020, 812: 152097.