Mechanical and physical behavior of newly developed functionally graded materials and composites of stainless steel 316L with calcium silicate and hydroxyapatite.

This study aimed to investigate the structural, physical and mechanical behavior of composites and functionally graded materials (FGMs) made of stainless steel (SS-316L)/hydroxyapatite (HA) and SS-316L/calcium silicate (CS) employing powder metallurgical solid state sintering. The structural analysis using X-ray diffraction showed that the sintering at high temperature led to the reaction between compounds of the SS-316L and HA, while SS-316L and CS remained intact during the sintering process in composites of SS-316L/CS. A dimensional expansion was found in the composites made of 40 and 50 wt% HA.

In Vitro Study of Surface Modified Poly(ethylene glycol)-Impregnated Sintered Bovine Bone Scaffolds on Human Fibroblast Cells.

Scaffold design from xenogeneic bone has the potential for tissue engineering (TE). However, major difficulties impede this potential, such as the wide range of properties in natural bone. In this study, sintered cortical bones from different parts of a bovine-femur impregnated with biodegradable poly(ethylene glycol) (PEG) binder by liquid phase adsorption were investigated.

A comparison in mechanical properties of cermets of calcium silicate with Ti-55Ni and Ti-6Al-4V alloys for hard tissues replacement.

This study investigated the impact of calcium silicate (CS) content on composition, compressive mechanical properties, and hardness of CS cermets with Ti-55Ni and Ti-6Al-4V alloys sintered at 1200°C. The powder metallurgy route was exploited to prepare the cermets. New phases of materials of Ni16Ti6Si7, CaTiO3, and Ni31Si12 appeared in cermet of Ti-55Ni with CS and in cermet of Ti-6Al-4V with CS, the new phases Ti5Si3, Ti2O, and CaTiO3, which were emerged during sintering at different CS content (wt%).

Comparison of various functionally graded femoral prostheses by finite element analysis.

This study is focused on finite element analysis of a model comprising femur into which a femoral component of a total hip replacement was implanted. The considered prosthesis is fabricated from a functionally graded material (FGM) comprising a layer of a titanium alloy bonded to a layer of hydroxyapatite. The elastic modulus of the FGM was adjusted in the radial, longitudinal, and longitudinal-radial directions by altering the volume fraction gradient exponent.

Development of an air pneumatic suspension system for transtibial prostheses.

The suspension system and socket fitting of artificial limbs have major roles and vital effects on the comfort, mobility, and satisfaction of amputees. This paper introduces a new pneumatic suspension system that overcomes the drawbacks of current suspension systems in donning and doffing, change in volume during daily activities, and pressure distribution in the socket-stump interface. An air pneumatic suspension system (APSS) for total-contact sockets was designed and developed.

Effect of geometrical parameters on the performance of longitudinal functionally graded femoral prostheses.

This study aimed to assess the performance of different longitudinal functionally graded femoral prostheses. This study was also designed to develop an appropriate prosthetic geometric design for longitudinal functionally graded materials. Three-dimensional models of the femur and prostheses were developed and analyzed.

Finite element analysis on longitudinal and radial functionally graded femoral prosthesis.

This study focused on developing a 3D finite element model of functionally graded femoral prostheses to decrease stress shielding and to improve total hip replacement performance. The mechanical properties of the modeled functionally graded femoral prostheses were adjusted in the sagittal and transverse planes by changing the volume fraction gradient exponent. Prostheses with material changes in the sagittal and transverse planes were considered longitudinal and radial prostheses, respectively.