Next Article in Journal
Variation of Relief Topography and Hardness of Surface Layers of Materials Due to Impact-Oscillatory Loading
Previous Article in Journal
Influence of Binder Property and Mortar Thickness on High-Temperature Performance of Cold Recycled Mixtures with Asphalt Emulsion
Open AccessArticle

Ultrasonic Measurement of Stress in SLM 316L Stainless Steel Forming Parts Manufactured Using Different Scanning Strategies

College of Material Science and Mechanical Engineering, Beijing Technology and Business University, Beijing 102488, China
*
Author to whom correspondence should be addressed.
Materials 2019, 12(17), 2719; https://doi.org/10.3390/ma12172719
Received: 22 July 2019 / Revised: 17 August 2019 / Accepted: 23 August 2019 / Published: 25 August 2019
Selective Laser Melting (SLM) technology is a new kind of additive manufacturing technology developed in in the last decade. Measurement and control of stress in metal forming layer is the basic problem of SLM forming parts. Critical Refraction Longitudinal (LCR) wave method was used to measure stress. The acoustic-elastic formulas for measuring stresses in SLM 316L stainless steel forming parts manufactured using meander, stripe, and chess board scanning strategies, respectively, were established based on static load tensile test. The experimental results show that the acoustic time difference of LCR wave in SLM specimen manufactured with 316L stainless steel increases linearly with the increase of stress when the tensile stress is less than critical stress (372 MPa, 465 MPa, and 494 MPa). Due to the inhomogeneous deformation of the anisotropic SLM forming layer and the dimple-micropore aggregation fracture mechanism, the acousto-elastic curve fluctuates up and down along the irregular curve when the tensile stress is larger than critical stress. The results of corroboration experiments show that nondestructive measurement of stress in SLM forming specimen can be realized by using LCR wave method. The scanning strategy can significantly affect the tensile strength and yield strength of SLM forming specimen. The stresses were all in tension stress state at the edge of the specimens, whatever scanning strategy was used. Sub-area scanning and scanning sequence of alternate and intersect were adopted, which can effectively reduce the stress in the SLM forming specimen. The overall stress values of SLM forming specimen manufactured using chess board scanning strategy were smaller than that using meander and stripe strategies. The distribution of stress were more uniform. View Full-Text
Keywords: SLM forming parts; additive manufacturing; scanning strategies; stress; critical refraction longitudinal wave SLM forming parts; additive manufacturing; scanning strategies; stress; critical refraction longitudinal wave
Show Figures

Figure 1

MDPI and ACS Style

Yan, X.; Pang, J.; Jing, Y. Ultrasonic Measurement of Stress in SLM 316L Stainless Steel Forming Parts Manufactured Using Different Scanning Strategies. Materials 2019, 12, 2719. https://doi.org/10.3390/ma12172719

AMA Style

Yan X, Pang J, Jing Y. Ultrasonic Measurement of Stress in SLM 316L Stainless Steel Forming Parts Manufactured Using Different Scanning Strategies. Materials. 2019; 12(17):2719. https://doi.org/10.3390/ma12172719

Chicago/Turabian Style

Yan, Xiaoling; Pang, Jincheng; Jing, Yanlong. 2019. "Ultrasonic Measurement of Stress in SLM 316L Stainless Steel Forming Parts Manufactured Using Different Scanning Strategies" Materials 12, no. 17: 2719. https://doi.org/10.3390/ma12172719

Find Other Styles
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Search more from Scilit
 
Search
Back to TopTop