Abstract
The laser powder bed fusion (L-PBF) method of additive manufacturing (AM) is increasingly used in various industrial manufacturing fields due to its high material utilization and design freedom of parts. However, the parts produced by L-PBF usually contain such defects as crack and porosity because of the technological characteristics of L-PBF, which affect the quality of the product. Laser ultrasonic testing (LUT) is a potential technology for on-line testing of the L-PBF process. It is a non-contact and non-destructive approach based on signals from abundant waveforms with a wide frequency-band. In this study, a method of LUT for on-line inspection of L-PBF process was proposed, and a system of LUT was established approaching the actual environment of on-line detection to evaluate the method applicability for defects detection of L-PBF parts. The detection results of near-surface defects in L-PBF 316L stainless steel parts show that the crack-type defects with a sub-millimeter level within 0.5 mm depth can be identified, and accordingly, the positions and dimensions information can be acquired. The results were verified by X-ray computed tomography, which indicates that the present method exhibits great potential for on-line inspection of AM processes.
Article PDF
Similar content being viewed by others
Avoid common mistakes on your manuscript.
References
Zhang Y, Wu L M, Guo X Y, et al. Additive manufacturing of metallic materials: A review. Journal of Materials Engineering and Performance, 2017, 27(1): 1–13.
Debroy T, Wei H L, Zuback J S, et al. Additive manufacturing of metallic components — Process, structure and properties. Progress in Materials Science, 2018, 92: 112–224.
Gong H J, Rafi K, Gu H F, et al. Analysis of defect generation in Ti-6Al-4V parts made using powder bed fusion additive manufacturing processes. Additive Manufacturing, 2014, 1–4: 87–98.
Zhang B, Li Y T, Bai Q. Defect formation mechanisms in selective laser melting: A review. Chinese Journal of Mechanical Engineering, 2017, 30(3): 515–527.
Song B, Dong S J, Zhang B C, et al. Effects of processing parameters on microstructure and mechanical property of selective laser melted Ti6Al4V. Materials & Design, 2012, 35: 120–125.
Ziółkowski G, Chlebus E, Szymczyk P, et al. Application of X-ray CT method for discontinuity and porosity detection in 316L stainless steel parts produced with SLM technology. Archives of Civil and Mechanical Engineering, 2014, 14(4): 608–614.
Sol T, Hayun S, Noiman D, et al. Nondestructive ultrasonic evaluation of additively manufactured AlSi10Mg samples. Additive Manufacturing, 2018, 22: 700–707.
Rometsch Paul A, Pelliccia D, Tomus D, et al. Evaluation of polychromatic X-ray radiography defect detection limits in a sample fabricated from Hastelloy X by selective laser melting. NDT & E International, 2014, 62: 184–192.
Song Y F, Zi X H, Fu Y D, et al. Nondestructive testing of additively manufactured material based on ultrasonic scattering measurement. Measurement, 2018, 118: 105–112.
Lott P, Schleifenbaum H, Meiners W, et al. Design of an optical system for the in situ process monitoring of selective laser melting (SLM). Physics Procedia, 2011, 12: 683–690.
Repossini G, Laguzza V, Grasso M, et al. On the use of spatter signature for in-situ monitoring of laser powder bed fusion. Additive Manufacturing, 2017, 16: 35–48.
Lu Q Y, Nguyen N V, Hum A J W, et al. Optical in-situ monitoring and correlation of density and mechanical properties of stainless steel parts produced by selective laser melting process based on varied energy density. Journal of Materials Processing Technology, 2019, 271: 520–531.
Zhao C, Fezzaa K, Cunningham R W, et al. Real-time monitoring of laser powder bed fusion process using high-speed X-ray imaging and diffraction. Scientific Reports, 2017, 7(1): 3602.
Leung C L A, Marussi S, Atwood R C, et al. In situ X-ray imaging of defect and molten pool dynamics in laser additive manufacturing. Nature Communication, 2018, 9(1): 1355.
Zeng W, Yao Y Y, Qi S K, et al. Finite element simulation of laser-generated surface acoustic wave for identification of subsurface defects. Optik, 2020, 207: 163812.
Choi S, Jhang K Y. Internal defect detection using lasergenerated longitudinal waves in ablation regime. Journal of Mechanical Science and Technology, 2018, 32(9): 4191–4200.
Zhan Y, Xu H X, Du W Q, et al. Research on the influence of heat treatment on residual stress of TC4 alloy produced by laser additive manufacturing based on laser ultrasonic technique. Ultrasonics, 2021, 115: 106466.
Ma Y Y, Hu Z L, Tang Y, et al. Laser opto-ultrasonic dual detection for simultaneous compositional, structural, and stress analyses for wire + arc additive manufacturing. Additive Manufacturing, 2020, 31: 100956.
Everton S, Dickens P, Tuck C, et al. Using laser ultrasound to detect subsurface defects in metal laser powder bed fusion components. JOM, 2018, 70(3): 378–383.
Millon C, Vanhoye A, Obaton A F, et al. Development of laser ultrasonics inspection for online monitoring of additive manufacturing. Welding in the World, 2018, 62(3): 653–661.
Smith R J, Hirsch M, Patel R, et al. Spatially resolved acoustic spectroscopy for selective laser melting. Journal of Materials Processing Technology, 2016, 236: 93–102.
Davis G, Nagarajah R, Palanisamy S, et al. Laser ultrasonic inspection of additive manufactured components. The International Journal of Advanced Manufacturing Technology, 2019, 102(5–8): 2571–2579.
Truong T C, Lee J R. SNR enhancement for composite application using multiple Doppler vibrometers based laser ultrasonic propagation imager. Optics & Lasers in Engineering, 2016, 84: 82–88.
Chen D, Lü G L, Guo S F, et al. Subsurface defect detection using phase evolution of line laser-generated Rayleigh waves. Optics & Laser Technology, 2020, 131: 106410.
Acknowledgement
This work was financially supported by the National Key R&D Program of China (Grant No. 2018YFB1106100).
Author information
Authors and Affiliations
Corresponding author
Additional information
Hui Ding Chief Professor. His research interests mainly focus on the computational materials science, special structural material damage, and nondestructive testing technology. Prof. Ding is a Member of the Advanced Manufacturing Department of Science & Technology Commission of Ministry of Education. He has presided over a number of national key research and development projects such as “High-frequency Ultrasonic Testing Technology and Equipment for Metal Additive Manufacturing”. He won the second prize of the National Science and Technology Progress Award in 2017.
Rights and permissions
About this article
Cite this article
Dai, T., Jia, Xj., Zhang, J. et al. Laser ultrasonic testing for near-surface defects inspection of 316L stainless steel fabricated by laser powder bed fusion. China Foundry 18, 360–368 (2021). https://doi.org/10.1007/s41230-021-1063-1
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s41230-021-1063-1
Key words
- additive manufacturing
- 316L stainless steel
- on-line inspection
- laser ultrasonic testing
- non-destructive testing