journal article·2020-07

On the notch fatigue strength of additively manufactured polylactide (PLA)

O.H. Ezeh, L. Susmel

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Abstract

The strength and cracking behaviour under fatigue loading of additively manufactured polylactide (PLA) was investigated experimentally to quantify and model the role of notches. These tests were run under load ratios equal to -1 and to 0. Being supported by the experimental evidence, 3Dprinted PLA was treated as a linear-elastic, isotropic, and homogenous material. This allowed the use of the Theory of Critical Distances to be extended also to the fatigue assessment of notched 3D-printed PLA. This theory was seen to return accurate estimates. This confirms that it can be used also to estimate fatigue lifetime of notched 3D-printed polymers.
Source: openaire · Quality: candidate unverified · Source record ↗

Research context

OpenAlex topics: Additive Manufacturing and 3D Printing Technologies · Bone Tissue Engineering Materials · 3D Printing in Biomedical Research

SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.

References (30)

Show source-provided references
1. The impact of process parameters on mechanical properties of parts fabricated in PLA with an open-source 3-D printer10.1108/RPJ-09-2014-0135 ↗
2. Orthotropic mechanical properties of fused deposition modelling parts described by classical laminate theory10.1016/j.matdes.2015.11.009 ↗
3. Additive manufacturing of PLA structures using fused deposition modelling: Effect of process parameters on mechanical properties and their optimal selection10.1016/j.matdes.2017.03.065 ↗
4. Measurements of the mechanical response of unidirectional 3D-printed PLA10.1016/j.matdes.2017.03.051 ↗
5. A material length scale based methodology to assess static strength of notched additively manufactured polylactide (PLA)10.1111/ffe.12746 ↗
6. Static assessment of plain/notched polylactide (PLA) 3D-printed with different in-fill levels: equivalent homogenised material concept and Theory of Critical Distances10.1111/ffe.12958 ↗
7. Letcher T, Waytashek M. Material property testing of 3D-printed specimen in PLA on an entry-level 3D-printer. In: Proceedings of the ASME 2014 International Mechanical Engineering Congress & Exposition (IMECE2014), 14-20 November 2014, Montreal, Quebec, Canada, IMECE2014-39379.10.1115/IMECE2014-39379 ↗
8. Effects of part build orientations on fatigue behaviour of FDM-processed PLA material10.1007/s40964-015-0002-3 ↗
9. Fatigue lifespan study of PLA parts obtained by additive manufacturing10.1016/j.promfg.2017.09.146 ↗
10. Fatigue strength of additively manufactured polylactide (PLA): effect of raster angle and non-zero mean stresses10.1016/j.ijfatigue.2019.05.014 ↗
11. Reference strength values to design against static and fatigue loading polylactide additively manufactured with in-fill level equal to 100%
12. Taylor · 2007
13. The Theory of Critical Distances: a review of its applications in fatigue10.1016/j.engfracmech.2006.12.004 ↗
14. Susmel · 2009
15. Anon. Standard Test Method for Uniaxial Fatigue Properties of Plastics. ASTM D7791; 2017.
16. Anon. Standard Practice for Conducting Force Controlled Constant Amplitude Axial Fatigue Tests of Metallic Materials. ASTM E466; 2011.
17. Anon. Japan Society of Mechanical Engineers, Standard method of statistical fatigue testing. JSME S 002-1981, 1981.
18. Anon. Standard Practice for Statistical Analysis of Linear or Linearized Stress-Life (S-N) and Strain-Life (ε-N) Fatigue Data. ASTM E739; 2015.
19. Spindel JE, Haibach E. Some considerations in the statistical determination of the shape of S-N cruves. In: Statistical Analysis of Fatigue Data, ASTM STP 744 (Edited by Little, R. E. and Ekvall, J. C.), pp. 89–113, 1981.10.1520/STP29330S ↗
20. On the accuracy of nominal, structural, and local stress based approaches in designing aluminium welded joints against fatigue10.1016/j.ijfatigue.2016.11.002 ↗
21. Neuber H. Theory of notch stresses: principles for exact calculation of strength with reference to structural form and material. Springer Verlag, Berlin, II Ed. 1958.
22. Peterson RE. Notch Sensitivity. In: Sines G., Waisman J. L., Editors. Metal Fatigue. New York. McGraw Hill 1959;293-306.
23. A unifying approach to estimate the high-cycle fatigue strength of notched components subjected to both uniaxial and multiaxial cyclic loadings10.1111/j.1460-2695.2004.00759.x ↗
24. The Theory of Critical Distances: A link to micromechanisms10.1016/j.tafmec.2017.05.018 ↗
25. Susmel L. Taylor, D., A novel formulation of the Theory of Critical Distances to estimate Lifetime of Notched Components in the Medium-Cycle Fatigue Regime. Fatigue Fract Eng Mater Struct 2007;30(7):567-581.10.1111/j.1460-2695.2007.01122.x ↗
26. The Theory of Critical Distances to estimate lifetime of notched components subjected to variable amplitude uniaxial fatigue loading10.1016/j.ijfatigue.2011.01.012 ↗
27. Engineering formulae for fatigue strength reduction due to crack-like notches10.1007/BF00942722 ↗
28. Geometrical effects in fatigue: a unifying theoretical model10.1016/S0142-1123(99)00007-9 ↗
29. Field effects in fatigue crack initiation: long life fatigue strength10.1115/1.2912768 ↗
30. The fatigue behaviour of three-dimensional stress concentrations10.1016/j.ijfatigue.2004.07.006 ↗