Tensile Mechanical Properties of Micro-Selective Laser Melted 316L Stainless Steel

doi:10.11900/0412.1961.2022.00041

Acta Metall Sin

2024, Vol. 60

Issue (2): 211-219 DOI: 10.11900/0412.1961.2022.00041

Research paper

Current Issue | Archive | Adv Search

Tensile Mechanical Properties of Micro-Selective Laser Melted 316L Stainless Steel

ZHANG Nan¹^,², ZHANG Haiwu², WANG Miaohui¹^,²(

)

1 China Machinery Institute of Advanced Materials Co. Ltd., Zhengzhou 450001, China
2 China Academy of Mechanical Science and Technology Group Co. Ltd., Beijing 100044, China

Cite this article:

ZHANG Nan, ZHANG Haiwu, WANG Miaohui. Tensile Mechanical Properties of Micro-Selective Laser Melted 316L Stainless Steel. Acta Metall Sin, 2024, 60(2): 211-219.

Download:

HTML

PDF(2840KB)
Export: BibTeX | EndNote (RIS)

Abstract

Compared with selective laser melting (SLM), the micro-SLM (M-SLM) technology offers the advantages of small spot diameter (< 20 μm), high forming precision (20-50 μm), and surface roughness (R_a) of up 1 μm, which implies that the M-SLM technology provides great potential for promotion and application in communication electronics, biomedical, and other fields in the future. In this work, 316L stainless steel was prepared using M-SLM, and its tensile properties and fracture behavior were studied. The microstructures of transverse and longitudinal tensile specimens were also investigated. In addition, the fracture morphology was characterized and analyzed, and the grain orientation and grain-boundary-characteristic distribution in the near-section plastic-deformation zone were further analyzed using electron backscatter diffraction (EBSD). The results showed that the 316L stainless steel prepared by M-SLM had a cellular structure with a size of 100-300 nm inside the grains. The tensile fracture was dimple-shaped, and the average dimple diameter was 80-500 nm, which allowed the transverse average tensile strength of the 316L stainless steel to reach 692.1 MPa, the longitudinal average elongation after fracture was 54.6%, which were obviously better than that of the 316L stainless steel prepared using traditional SLM. The appearance of austenite Σ3 twin boundaries in the stretching process of the 316L stainless steel prepared by M-SLM was related to the grain orientation, which could more likely appear in grains with an orientation close to <111>. Further analysis indicated that the appearance of Σ3 grain boundaries blocked the connectivity of the special grain-boundary network. Statistical analysis of the coherent Σ3 (Σ3_c) and incoherent Σ3 (Σ3_ic) grain boundaries using the EBSD-based rectangular-section method revealed that the amount percentages of Σ3_c and Σ3_ic in the near-fracture region of the 316L transverse tensile specimen were approximately 43% and 57%, respectively. Meanwhile, the amount percentage of Σ3_c in the same region of the 316L longitudinal tensile specimen increased to approximately 70%. The increase in the coherent Σ3_c twin boundary reduced the total grain-boundary energy, which explained why the longitudinal tensile strength of the 316L stainless steel prepared by M-SLM was generally lower than the transverse tensile strength.

Key words: micro-selective laser melting 316L stainless steel tensile property Σ3 boundary twinning

Received: 14 February 2022

ZTFLH:

TG142

Fund: National Natural Science Foundation of China(51975240);Beijing Natural Science Foundation(2222093);Technical Development Foundation of China Academy of Machinery Science and Technology Group Co. Ltd(812201Q9)

Corresponding Authors: WANG Miaohui, professor, Tel: (010)60603546, E-mail: wangmh0103@163.com

	Service

	E-mail this article
	Add to citation manager
	E-mail Alert
	RSS
	Collect articles（0）
	Articles by authors
	ZHANG Nan
	ZHANG Haiwu
	WANG Miaohui

URL:

https://www.ams.org.cn/EN/10.11900/0412.1961.2022.00041 OR https://www.ams.org.cn/EN/Y2024/V60/I2/211

Fig.1 Schematic of tensile sample using micro-selective laser melting (M-SLM) (unit: mm)

Fig.2 SEM image of 316L stainless steel powders

Fig.3 XRD spectrum of M-SLMed 316L stainless steel

Fig.4 SEM images of M-SLMed transverse direction (a-c) and longitudinal direction (d-f) 316L stainless steel specimens with different magnifications

Fig.5 Tensile engineering stress-strain curves of 316L stainless steel fabricated by M-SLM

Table 1 Tensile properties of M-SLMed 316L stainless steel with different building directions

Fig.6 Comparisons of tensile properties of M-SLMed 316L stainless steel and fabricated by traditional SLM

Fig.7 Low (a, c) and high (b, d) magnified SEM images showing the tensile fracture surfaces of transverse direction (a, b) and longitudinal direction (c, d) M-SLMed 316L stainless steel samples (Arrows in Fig.7c show the dimples formed by defects such as pores or keyholes)

Fig.8 EBSD analyses of microstructures in tensile fracture zone of 316L stainless steel transverse (a-c) and longitudinal (d-f) specimens prepared by M-SLM

Fig.9 Twin grains standard orientation triangular map in tensile fracture zone of 316L stainless steel longitudinal specimen prepared by M-SLM

Fig.10 Schematic of Σ3 grain boundary determination on the circle area in Fig.8b using micro rectangular section method ( N₁ and N₂ represent normal directions adjacent to grain boundaries of rectangle 1 and rectangle 2, respectively)

Table 2 Σ3 grain boundary analysis results in Figs.8b and e

1	Lan H B, Li D C, Lu B H. Micro- and nanoscale 3D printing [J]. Sci. Sin. Technol., 2015, 45: 919 doi: 10.1360/N092014-00397
	兰红波, 李涤尘, 卢秉恒. 微纳尺度3D打印 [J]. 中国科学: 技术科学, 2015, 45: 919
2	Liu G, Zhang X F, Chen X L, et al. Additive manufacturing of structural materials [J]. Mater. Sci. Eng., 2021, R145: 100596
3	Gunasekaran J, Sevvel P, Solomon I J. Metallic materials fabrication by selective laser melting: A review [J]. Mater. Today Proc., 2020, 37: 252
4	Jin X Y, Lan L, He B, et al. A review on surface roughness of metals parts fabricated by selective laser melting [J]. Mater. Rep., 2021, 35: 3168
	金鑫源, 兰亮, 何博等. 选区激光熔化成形金属零件表面粗糙度研究进展 [J]. 材料导报, 2021, 35: 3168
5	Zhang X Z, Chen L, Zhou J, et al. Simulation and experimental studies on process parameters, microstructure and mechanical properties of selective laser melting of stainless steel 316L [J]. J. Braz. Soc. Mech. Sci. Eng., 2020, 42: 402 doi: 10.1007/s40430-020-02491-3
6	Greco S, Gutzeit K, Hotz H, et al. Selective laser melting (SLM) of AISI 316L——Impact of laser power, layer thickness, and hatch spacing on roughness, density, and microhardness at constant input energy density [J]. Int. J. Adv. Manuf. Technol., 2020, 108: 1551 doi: 10.1007/s00170-020-05510-8
7	Stoll P, Spierings A, Wegener K. Impact of a process interruption on tensile properties of SS 316L parts and hybrid parts produced with selective laser melting [J]. Int. J. Adv. Manuf. Technol., 2019, 103: 367 doi: 10.1007/s00170-019-03560-1
8	Tascioglu E, Karabulut Y, Kaynak Y. Influence of heat treatment temperature on the microstructural, mechanical, and wear behavior of 316L stainless steel fabricated by laser powder bed additive manufacturing [J]. Int. J. Adv. Manuf. Technol., 2020, 107: 1947 doi: 10.1007/s00170-020-04972-0
9	Yang X Q, Liu Y, Ye J W, et al. Enhanced mechanical properties and formability of 316L stainless steel materials 3D-printed using selective laser melting [J]. Int. J. Miner. Metall. Mater., 2019, 26: 1396 doi: 10.1007/s12613-019-1837-2
10	Yang D C, Kan X F, Gao P F, et al. Influence of porosity on mechanical and corrosion properties of SLM 316L stainless steel [J]. Appl. Phys., 2022, 128A: 51
11	Yang X, Ma W J, Ren Y J, et al. Subgrain microstructures and tensile properties of 316L stainless steel manufactured by selective laser melting [J]. J. Iron Steel Res. Int., 2021, 28: 1159 doi: 10.1007/s42243-021-00561-x
12	Shin W S, Son B, Song W S, et al. Heat treatment effect on the microstructure, mechanical properties, and wear behaviors of stainless steel 316L prepared via selective laser melting [J]. Mater. Sci. Eng., 2021, A806: 140805
13	Wang Y M, Voisin T, McKeown J T, et al. Additively manufactured hierarchical stainless steels with high strength and ductility [J]. Nat. Mater., 2018, 17: 63 doi: 10.1038/nmat5021 pmid: 29115290
14	Shamsujjoha M, Agnew S R, Fitz-Gerald J M, et al. High strength and ductility of additively manufactured 316L stainless steel explained [J]. Metall. Mater. Trans., 2018, 49A: 3011
15	Kong D C, Dong C F, Wei S L, et al. About metastable cellular structure in additively manufactured austenitic stainless steels [J]. Addit. Manuf., 2021, 38: 101804
16	Nagarajan B, Hu Z H, Song X, et al. Development of micro selective laser melting: The state of the art and future perspectives [J]. Engineering, 2019, 5: 702 doi: 10.1016/j.eng.2019.07.002
17	Bertoli U S, Wolfer A J, Matthews M J, et al. On the limitations of volumetric energy density as a design parameter for selective laser melting [J]. Mater. Des., 2017, 113: 331 doi: 10.1016/j.matdes.2016.10.037
18	Brandon D G. The structure of high-angle grain boundaries [J]. Acta Metall., 1966, 14: 1479 doi: 10.1016/0001-6160(66)90168-4
19	Elmer J W, Allen S M, Eagar T W. Microstructural development during solidification of stainless steel alloys [J]. Metall. Trans., 1989, 20A: 2117
20	Zong X W, Gao Q, Zhou H Z, et al. Effects of bulk laser energy density on anisotropy of selective laser sintered 316L stainless steel [J]. Chin. J. Lasers, 2019, 46: 0502003
	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: 0502003
21	Lu L, Li Z B, Bi Z Y, et al. Relationship between tension toughness and fracture toughness of low carbon low alloy steel [J]. J. Iron Steel Res., 2014, 26(6): 67
	芦琳, 李周波, 毕宗岳等. 低碳低合金钢的静力韧度与断裂韧度 [J]. 钢铁研究学报, 2014, 26(6): 67
22	Gu D D, Chen H Y. Selective laser melting of high strength and toughness stainless steel parts: The roles of laser hatch style and part placement strategy [J]. Mater. Sci. Eng., 2018, A725: 419
23	Gu D D, Shi X Y, Poprawe R, et al. Material-structure-performance integrated laser-metal additive manufacturing [J]. Science, 2021, 372: eabg1487 doi: 10.1126/science.abg1487
24	Qi B, Liu Y D, Shi W T, et al. Study on overlap ratio of pulse laser selective melting forming [J]. Laser Technol., 2018, 42: 311
	祁斌, 刘玉德, 石文天等. 脉冲式激光选区熔化成形搭接率的研究 [J]. 激光技术, 2018, 42: 311
25	Ma Y Y, Liu Y D, Shi W T, et al. Effect of scanning speed on forming defects and properties of selective laser melted 316L stainless steel powder [J]. Laser Optoelectr. Progr., 2019, 56: 101403 doi: 10.3788/LOP
	马英怡, 刘玉德, 石文天等. 扫描速度对选区激光熔化316L不锈钢粉末成形缺陷及性能的影响 [J]. 激光与光电子学进展, 2019, 56: 101403
26	Shi W T, Wang P, Liu Y D, et al. Experimental study on surface quality and process of selective laser melting forming 316L [J]. Surface Technol., 2019, 48: 257
	石文天, 王朋, 刘玉德等. 选区激光熔化成形316L表面质量及工艺试验研究 [J]. 表面技术, 2019, 48: 257
27	Afkhami S, Dabiri M, Piili H, et al. Effects of manufacturing parameters and mechanical post-processing on stainless steel 316L processed by laser powder bed fusion [J]. Mater. Sci. Eng., 2021, A802: 140660
28	Kumar P, Jayaraj R, Suryawanshi J, et al. Fatigue strength of additively manufactured 316L austenitic stainless steel [J]. Acta Mater., 2020, 199: 225 doi: 10.1016/j.actamat.2020.08.033
29	Wu D J, Yu C S, Wang Q Y, et al. Synchronous-hammer-forging-assisted laser directed energy deposition additive manufacturing of high-performance 316L samples [J]. J. Mater. Process. Technol., 2022, 307: 117695 doi: 10.1016/j.jmatprotec.2022.117695
30	Matthews M J, Guss G, Khairallah S A, et al. Denudation of metal powder layers in laser powder bed fusion processes [J]. Acta Mater., 2016, 114: 33 doi: 10.1016/j.actamat.2016.05.017
31	Yu C F, Zhao C C, Zhang Z F, et al. Tensile properties of selective laser melted 316L stainless steel [J]. Acta Metall. Sin., 2020, 56: 683 doi: 10.11900/0412.1961.2019.00278
	余晨帆, 赵聪聪, 张哲峰等. 选区激光熔化316L不锈钢的拉伸性能 [J]. 金属学报, 2020, 56: 683 doi: 10.11900/0412.1961.2019.00278
32	Gutierrez-Urrutia I, Zaefferer S, Raabe D. The effect of grain size and grain orientation on deformation twinning in a Fe-22wt.%Mn-0.6wt.%C TWIP steel [J]. Mater. Sci. Eng., 2010, A527: 3552
33	Sun S J, Tian Y Z, Lin H R, et al. Transition of twinning behavior in CoCrFeMnNi high entropy alloy with grain refinement [J]. Mater. Sci. Eng., 2018, A712: 603
34	de Campos M F, Loureiro S A, Rodrigues D, et al. Estimative of the stacking fault energy for a FeNi(50/50) alloy and a 316L stainless steel [J]. Mater. Sci. Forum, 2008, 591-593: 3 doi: 10.4028/www.scientific.net/MSF.591-593

[1]	ZHANG Zhefeng, LI Keqiang, CAI Tuo, LI Peng, ZHANG Zhenjun, LIU Rui, YANG Jinbo, ZHANG Peng. Effects of Stacking Fault Energy on the Deformation Mechanisms and Mechanical Properties of Face-Centered Cubic Metals[J]. 金属学报, 2023, 59(4): 467-477.
[2]	WANG Di, HE Lili, WANG Dong, WANG Li, ZHANG Siqian, DONG Jiasheng, CHEN Lijia, ZHANG Jian. Influence of Pt-Al Coating on Tensile Properties of DD413 Alloy at High Temperatures[J]. 金属学报, 2023, 59(3): 424-434.
[3]	SUN Tengteng, WANG Hongze, WU Yi, WANG Mingliang, WANG Haowei. Effect ofIn Situ 2%TiB₂ Particles on Microstructure and Mechanical Properties of 2024Al Additive Manufacturing Alloy[J]. 金属学报, 2023, 59(1): 169-179.
[4]	ZHOU Hongwei, GAO Jianbing, SHEN Jiaming, ZHAO Wei, BAI Fengmei, HE Yizhu. Twin Boundary Evolution Under Low-Cycle Fatigue of C-HRA-5 Austenitic Heat-Resistant Steel at High Temperature[J]. 金属学报, 2022, 58(8): 1013-1023.
[5]	CHEN Yang, MAO Pingli, LIU Zheng, WANG Zhi, CAO Gengsheng. Detwinning Behaviors and Dynamic Mechanical Properties of Precompressed AZ31 Magnesium Alloy Subjected to High Strain Rates Impact[J]. 金属学报, 2022, 58(5): 660-672.
[6]	DING Ning, WANG Yunfeng, LIU Ke, ZHU Xunming, LI Shubo, DU Wenbo. Microstructure, Texture, and Mechanical Properties of Mg-8Gd-1Er-0.5Zr Alloy by Multi-Directional Forging at High Strain Rate[J]. 金属学报, 2021, 57(8): 1000-1008.
[7]	LIU Xianfeng, LIU Dong, LIU Renci, CUI Yuyou, YANG Rui. Microstructure and Tensile Properties of Ti-43.5Al-4Nb-1Mo-0.1B Alloy Processed by Hot Canned Extrusion[J]. 金属学报, 2020, 56(7): 979-987.
[8]	LI Yuancai, JIANG Wugui, ZHOU Yu. Effect of Nanopores on Tensile Properties of Single Crystal/Polycrystalline Nickel Composites[J]. 金属学报, 2020, 56(5): 776-784.
[9]	YU Chenfan, ZHAO Congcong, ZHANG Zhefeng, LIU Wei. Tensile Properties of Selective Laser Melted 316L Stainless Steel[J]. 金属学报, 2020, 56(5): 683-692.
[10]	ZHANG Zhefeng,SHAO Chenwei,WANG Bin,YANG Haokun,DONG Fuyuan,LIU Rui,ZHANG Zhenjun,ZHANG Peng. Tensile and Fatigue Properties and Deformation Mechanisms of Twinning-Induced Plasticity Steels[J]. 金属学报, 2020, 56(4): 476-486.
[11]	SUN Heng,LIN Xiaoping,ZHOU Bing,ZHAO Shengshi,TANG Qin,DONG Yun. Microstructures and Tensile Deformation Behavior of Directionally Solidified Mg-xGd-0.5Y Alloys[J]. 金属学报, 2020, 56(3): 340-350.
[12]	WANG Shihong,LI Jian,GE Xin,CHAI Feng,LUO Xiaobing,YANG Caifu,SU Hang. Microstructural Evolution and Work Hardening Behavior of Fe-19Mn Alloy Containing Duplex Austenite and ε-Martensite[J]. 金属学报, 2020, 56(3): 311-320.
[13]	WANG Xi,LIU Renci,CAO Ruxin,JIA Qing,CUI Yuyou,YANG Rui. Effect of Cooling Rate on Boride and Room Temperature Tensile Properties of β-Solidifying γ-TiAl Alloys[J]. 金属学报, 2020, 56(2): 203-211.
[14]	Liping DENG,Kaixuan CUI,Bingshu WANG,Hongliang XIANG,Qiang LI. Microstructure and Texture Evolution of AZ31 Mg Alloy Processed by Multi-Pass Compressing Under Room Temperature[J]. 金属学报, 2019, 55(8): 976-986.
[15]	Zheng LIU,Jianrong LIU,Zibo ZHAO,Lei WANG,Qingjiang WANG,Rui YANG. Microstructure and Tensile Property of TC4 Alloy Produced via Electron Beam Rapid Manufacturing[J]. 金属学报, 2019, 55(6): 692-700.

No Suggested Reading articles found!

Viewed

Full text

Abstract

Cited

Shared

Discussed