Effect of porosity and environment on the mechanical behavior of acrylic bone cement modified with acrylonitrile-butadiene-styrene particles: Part II. Fatigue crack propagation

1999 ◽  
Vol 48 (2) ◽  
pp. 128-134 ◽  
Author(s):  
M. M. Vila ◽  
M. P. Ginebra ◽  
F. J. Gil ◽  
J. A. Planell
Keyword(s):  
Fatigue Crack ◽  
Crack Propagation ◽  
Mechanical Behavior ◽  
Bone Cement ◽  
Fatigue Crack Propagation ◽  
Acrylonitrile Butadiene Styrene ◽  
Acrylic Bone Cement ◽  
Butadiene Styrene

scholarly journals Alternative radiopacifiers for polymethyl methacrylate bone cements: Silane-treated anatase titanium dioxide and yttria-stabilised zirconium dioxide

2021 ◽  
Vol 35 (10) ◽  
pp. 1235-1252
Author(s):  
Wayne Nishio Ayre ◽  
Nicole Scully ◽  
Carole Elford ◽  
Bronwen AJ Evans ◽  
Wendy Rowe ◽  
...  
Keyword(s):  
Titanium Dioxide ◽  
Fatigue Crack ◽  
Crack Propagation ◽  
Bone Cement ◽  
Fatigue Crack Propagation ◽  
Zirconium Dioxide ◽  
Bending Strength ◽  
Cell Attachment ◽  
Pmma Bone Cement

Poly (methyl methacrylate) (PMMA) bone cement is widely used for anchoring joint arthroplasties. In cement brands approved for these procedures, micron-sized particles (usually barium sulphate, BaSO4) act as the radiopacifier. It has been postulated that these particles act as sites for crack initiation and subsequently cement fatigue. This study investigated whether alternative radiopacifiers, anatase titanium dioxide (TiO2) and yttria-stabilised zirconium dioxide (ZrO2), could improve the in vitro mechanical, fatigue crack propagation and biological properties of polymethyl methacrylate (PMMA) bone cement and whether their coating with a silane could further enhance cement performance. Cement samples containing 0, 5, 10, 15, 20 and 25%w/w TiO2 or ZrO2 and 10%w/w silane-treated TiO2 or ZrO2 were prepared and characterised in vitro in terms of radiopacity, compressive and bending strength, bending modulus, fatigue crack propagation, hydroxyapatite forming ability and MC3T3-E1 cell attachment and viability. Cement samples with greater than 10%w/w TiO2 and ZrO2 had a similar radiopacity to the control 10%w/w BaSO4 cement and commercial products. The addition of TiO2 and ZrO2 to bone cement reduced the bending strength and fracture toughness and increased fatigue crack propagation due to the formation of agglomerations and voids. Silane treating TiO2 reversed this effect, enhancing the dispersion and adhesion of particles to the PMMA matrix and resulted in improved mechanical properties and fatigue crack propagation resistance. Silane-treated TiO2 cements had increased nucleation of hydroxyapatite and MC3T3-E1 cell attachment in vitro, without significantly compromising cell viability. This research has demonstrated that 10%w/w silane-treated anatase TiO2 is a promising alternative radiopacifier for PMMA bone cement offering additional benefits over conventional BaSO4 radiopacifiers.

Finite Element Analysis of the Effect of Residual Stress on Mechanical Behavior of Welded Plates

2008 ◽  
Vol 580-582 ◽  
pp. 605-608
Author(s):  
Byeong Choon Goo ◽  
Seung Yong Yang
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Fatigue Crack ◽  
Residual Stresses ◽  
Crack Propagation ◽  
Mechanical Behavior ◽  
Fatigue Crack Propagation ◽  
Cohesive Zone Model ◽  
Zone Model ◽  
Element Analysis

Residual stresses play an important role in the mechanical behavior of steels and welded structures. To examine the effect of residual stresses on tensile behavior and fatigue, residual stresses in the specimens were generated by welding. Experimental stress-strain curves of the specimens with/without residual stresses were obtained and compared to simulated curves obtained by the finite element analysis. The two results are in a good agreement. Finally, to study the relaxation of the residual stresses during fatigue crack propagation, we carried out fatigue crack propagation analysis by a 3-D cohesive zone model. Initial welding residual stresses decrease as the number of cycles increases.

Sign in / Sign up

Export Citation Format

Share Document