• Matic Bombek University Rehabilitation Institute, Republic of Slovenia, Ljubljana, Slovenia
  • Uroš Vesenjak University Rehabilitation Institute, Republic of Slovenia, Ljubljana, Slovenia
  • Marko Pisek University Rehabilitation Institute, Republic of Slovenia, Ljubljana, Slovenia
  • Gaj Vidmar University Rehabilitation Institute, Republic of Slovenia, Ljubljana, Slovenia
  • Sašo Knez Aereform Ltd., Trbovlje, Slovenia
  • Sergej Medved University of Ljubljana, Biotechnical Faculty, Department of Wood Science and Technology, Ljubljana, Slovenia
Keywords: composite materials, lamination, prosthetic socket, laboratory testing


The mechanical properties of the composite materials for prosthetic sockets are a key determinant of the quality and usability of prostheses. Our aim was to compare the existing materials used in production at our institution with some modified, potentially improved materials. We conducted an industrial experiment. The existing material (A) was compared with three newly produced materials that introduced changes in the lamination process: B1, where an infusion spiral tube was added; B2, where the resin was degassed; and B3, where a mesh and peel ply were used. The specimens underwent laboratory strength testing. The strength measurements were statistically analysed using one-way analysis of covariance (ANCOVA) that was adjusted for specimen thickness because of the observed negative correlation of thickness with strength. Material A had the highest bending strength, on average, but there were no statistically significant differences in the bending strength between the materials after adjusting for the specimen thickness (p = 0.941). Materials B1 and B2 exhibited statistically significantly lower tensile strengths than material A (p < 0.001). Material B3 had the lowest average tensile strength, but it could not be statistically distinguished from the others, because of the significantly larger average specimen thickness. The compressive strength was tested only for materials B1, B2 and B3; their averages did not differ statistically significantly (p = 0.291). Laboratory strength testing provided important insights into the differences between the various laminated composite prosthetics materials. We did not reach our initial goal to produce a better material, but we will continue our research and development in this field with a more systematic, technological approach.


1 M. Lifang, W. Yaxin, L. Yang, Y. Liu, S. Zhang, Y. Chen, Comparative study on prosthetic socket materials, Comput. Model. New Technol., 18 (2014) 8, 387–892
2 B. L. Klasson, Carbon fibre and fibre lamination in prosthetics and orthotics: some basic theory and practical advice for the practitioner, Prosthet. Orthot. Int., 19 (1995) 2, 74–91, doi:10.3109/ 03093649509080349
3 M. J. Gerschutz, M. L. Haynes, D. M. Nixon, J. M. Colvin, Tensile strength and impact resistance properties of materials used in prosthetic sockets, copolymer sockets and definitive laminated sockets, J. Rehabil. Res. Dev., 48 (2011) 8, 987–1004, doi:10.1682/jrrd.2010. 10.0204
4 S. L. Philips, W. Craelius, Material properties of selected prosthetic laminates, J. Prosthet. Orthot., 17 (2005) 1, 27–32, doi:10.1097/ 00008526-¬200501000-00007
5 S.-Y. Kim, C. S. Shim, C. Sturtevant, D. Kim, H. C. Song, Mechanical properties and fabrication quality of hand-layup and vacuum infusion processed hybrid composite materials for GFRP marine structures, Int. J. Nav. Arch. Ocean. 6 (2014) 3, 723–736, doi:10.2478/ IJNAOE-2013-0208
6 A. Kurşun, E. Topal, investigation of hole effects on the critical Buckling load of laminated composite plates, Mater. Technol., 50 (2016) 1, 23–27, doi:0.17222/mit.2014.164
7 G. Fernlund, J. Wells, L. Fahrang, J. Kay, A. Poursartip, Causes and remedies for porosity in composite fabrication. IOP Conf. Ser.: Mater. Sci. Eng., 139 (2016), 012002, doi:10.1088/1757-899X/139/ 1/012002
8 A. G. Stamopoulos, K. I. Tserpes, P. Prucha, Evaluation of porosity effects on the mechanical properties of carbon fiber reinforced plastic unidirectional laminates by x-ray computed tomography and mechanical testing, J. Compos. Mater., 50 (2015) 15, 2087–2098, doi:10.1177/0021998315602049
9 B. V. Babu Kiran, G. Harish, Effect of resin and thickness on tensile properties of laminated composites, Am. Int. J. Res. Sci. Technol. Eng. Math., 5 (2013) 2, 128–134
10 V. Faulkner, M. Field, J. W. Egan, N. M. Gall, Evaluation of high strength materials for prostheses, Orthotics Prosthet., 40 (1986) 4, 44–58
11 A. M. Muhammed, Experimental investigation of tensile and fatigue stresses for orthotic/ prosthetic composite materials with varying fiber (perlon, e-glass and carbon), ARPN J. Eng. Appl. Sci., 11 (2016) 21, 12820–12827
12 A. N. Hadi, J. K. Oleiwi, Improving tensile strength of polymer blends as prosthetic foot material reinforcement by carbon fiber, J. Material. Sci. Eng., 4 (2015) 2, 1000158, doi:10.4172/2169-¬0022.1000158
13 K. Al-Khazraji, J. Kadhim, P. S. Ahmed, Tensile and fatigue characteristic of lower-limb prosthetic socket made from composite materials, Proc. of the 2012 Inter. Conf. on Industrial Engineering and Operations Management, Istanbul 2012, 843–852
How to Cite
Bombek M, Vesenjak U, Pisek M, Vidmar G, Knez S, Medved S. MECHANICAL TESTING OF LAMINATED COMPOSITE MATERIALS FOR PROSTHETIC SOCKETS. MatTech [Internet]. 2021Sep.30 [cited 2021Nov.28];55(5):655–661. Available from: