title: Effects of microstructural inclusions on fatigue life of polyether ether ketone (PEEK).
abstract: In this study, the effects of microstructural inclusions on fatigue life of polyether ether ketone (PEEK) was investigated. Due to the versatility of its material properties, the semi-crystralline PEEK polymer has been increasingly adopted in a wide range of applications particularly as a biomaterial for orthopedic, trauma, and spinal implants. To obtain the cyclic behavior of PEEK, uniaxial fully-reversed strain-controlled fatigue tests were conducted at ambient temperature and at 0.02 mm/mm to 0.04 mm/mm strain amplitudes. The microstructure of PEEK was obtained using the optical and the scanning electron microscope (SEM) to determine the microstructural inclusion properties in PEEK specimen such as inclusion size, type, and nearest neighbor distance. SEM analysis was also conducted on the fracture surface of fatigue specimens to observe microstructural inclusions that served as the crack incubation sites. Based on the experimental strain-life results and the observed microstructure of fatigue specimens, a microstructure-sensitive fatigue model was used to predict the fatigue life of PEEK that includes both crack incubation and small crack growth regimes. Results show that the employed model is applicable to capture microstructural effects on fatigue behavior of PEEK.
authors: Center for Advanced Vehicular Systems, Mississippi State University, Box 5405, Mississippi State, MS 39762, USA. Electronic address: jutima@cavs.msstate.edu.
authors: Jutima
authors: J
authors: Simsiriwong
authors: Department for Mechanical Engineering, Mississippi State University, Box 9552, Mississippi State, MS 39762, USA.
authors: Rakish
authors: R
authors: Shrestha
authors: Center for Advanced Vehicular Systems, Mississippi State University, Box 5405, Mississippi State, MS 39762, USA; Department for Mechanical Engineering, Mississippi State University, Box 9552, Mississippi State, MS 39762, USA.
authors: Nima
authors: N
authors: Shamsaei
authors: Center for Advanced Vehicular Systems, Mississippi State University, Box 5405, Mississippi State, MS 39762, USA.
authors: Marcos
authors: M
authors: Lugo
authors: U.S. Army Engineer Research and Development Center, 3909 Halls Ferry Road, Vicksburg, MS 39180, USA.
authors: Robert D
authors: RD
authors: Moser
mesh_terms: D001577:Benzophenones; D007659:Ketones / Q000737:chemistry*; D008422:Materials Testing; D055595:Mechanical Phenomena; D008962:Models, Theoretical; D011092:Polyethylene Glycols / Q000737:chemistry*; D011108:Polymers; D013314:Stress, Mechanical
chemical_list: D001577:Benzophenones; D007659:Ketones; D011108:Polymers; C063834:polyetheretherketone; D011092:Polyethylene Glycols
keywords: Fatigue life estimation; Fatigue modeling; Polyether ether ketone (PEEK); Strain-life approach; Structure–property relations; Thermoplastics