Fracture resistance analysis of PEEK-polymer

Abstract

PEEK is a thermoplastic polymer with halfcrystallic structure – the scientific name of this material is poly(oxy-1,4-phenylene-oxy-1,4-phenylenecarbonyl-1,4-phenylene). It has a high melt and glass transition temperatures (T_m = 340 °C, T_g = 143 °C), high chemical resistance and is melt processable. Thus it has been used in a variety of structural and insulation applications. Nowadays, one of them is the biomedical application. The mechanical properties of PEEK have been extensively investigated in many research papers. However, there is not so high number of papers devoted to the fracture susceptibility of PEEK-material. Therefore, the the aim of this work is to present the results of studies on PEEK material with the use of fracture toughness test and digital image correlation. In order to conduct the tests, there were used two types of samples: SENB and CT. In comparison with other polymeric materials subjected to biomedical application, PEEK material presents relatively good fracture resistance with their biocompatibility.

Keywords:

• PEEK material
• fracture toughness
• DIC
• biomaterials
• fractography
• stress intensity factor

Additional information

Notes on contributors

Grzegorz Lesiuk

Grzegorz LESIUK, PhD Eng. is an assistant Professor at the Department of Mechanics, Materials Science and Engineering, Faculty of Mechanical Engineering at the Wrocław University of Science and Technology. The research field of dr Lesiuk is connected with the microstructural degradation processes and its potential influence on the mechanical properties of long term operated steel and composite structural members. Another important part of research is fracture mechanics and fatigue fracture in terms of energy methods. During the last years dr Lesiuk extensively cooperate with Polish and European companies in R+D, Energy, automotive and railway sector. Dr Lesiuk at Wroclaw University of Science and Technology conducts regular lectures and classes: classical mechanics, dynamics, differential equations, fracture mechanics.

Aleksandra Sawicka

Aleksandra SAWICKA. MSc Eng. Aleksandra Sawicka was a student of a Master’s Degree at the Faculty of Mechanical Engineering at the Wrocław University of Science and Technology. She graduated also with a Bachelor’s degree at the Faculty of Biomedical Engineering at the Silesian University of Technology. The main aim of MSc Aleksandra Sawicka’s thesis was to combine both field of science: biomedicine and mechanics into one failure analysis approach. The research field is focused on the use of fracture mechanics in failure analysis of the stabilization structures commonly used in medicine. One of the most important part of the research was to apply the SINTAP/FITNET procedure, toughness test and Digital Image Correlation to check the mechanical properties of the material (in particular polietheroetheroketon – PEEK) for the use of biomedical implants.

José Correia

José CORREIA, PhD Eng. born 1984 in Peso da Régua, Portugal, is Senior Researcher of Optics and Experimental Mechanics Laboratory (LOME) of INEGI/UP and CONSTRUCT/FEUP (Portugal). He is also Invited Professor at the structural mechanics section in the Civil Engineering Department of the University of Coimbra. He obtained the degrees BSc (2007) and MSc (2009) in Civil Engineering by the University of Trás-os-Montes e Alto Douro. He is specialist in steel and composite (steel and concrete) construction by the University of Coimbra in 2010. He is PhD in Civil Engineering by University of Porto in 2015. He is also co-author of more 30 papers in the most relevant scientific journals devoted to engineering materials and structures and 80 proceedings in international and national conferences, congresses and workshops. He is an expert in structural integrity, fatigue and fracture of materials and structures.

Roman Frątczak

Roman FRĄTCZAK, PhD Eng. is a President, founder and co-owner of Nobo Solultions S.A. For over 6 year employed as senior design engineer in R&D department (Poland and Switzerland) of an international company. Responsible for mechanical calculations of turbogenerator components and fatigue, fracture and dynamics analyses. Cooperated on R&D projects with Zielona Góra University and Wrocław Medical University in the field of anatomical structures and implants numerical modelling and development of relevant methods. In Nobo Solutions carries out current projects. Is also responsible for development of engineering software and designs non-standard measurement system for power generation industry. Author of a patent: (Application no WYN: 389059 – Excitation circuit of electric turgogenerator. Elastic connection of the excitation system).