It is obvious that all the elements in a metallic prosthesis implanted in the human body may have beneficial or detrimental effects on the tissue-prosthesis interference. For this reason, the precise knowledge of the chemical composition and structure of an implantable metallic material becomes a major requirement for estimating the medical prosthesis behavior and minimizing the risk of rejection of the implant by the human body. This paper presents an elemental and structural analysis of some potentially biocompatible materials, such as AISI 316 and Co-Cr-Mo alloys.
Additive Manufacturing (AM) concerns all classes of materials – polymers, metals, ceramics and glasses as well. For this reason, AM is in the focus of material scientists from all branches. Leaders of the industry realize that the possibilities of 3D printing are endless, and that these possibilities need ways and means to be taken full advantage of. Today, aerospace engineers are using the fused deposition modeling (FDM) method for rapid prototyping, part manufacturing, and tooling. They are followed by leaders and engineers from industry (industrial machines, motor vehicles, consumer products, medical/dental) but also from academic institutions and government/military.
The strength of materials is a complex function which involve two main components, material nature and the presence of defects. Usually glasses exhibit a fragile behavior due to a numerous flaws and the effect is a large range of data scattering in tensile strength measurement. The Weibull probability density function was applied to describe the scatter of experimental data in tensile test, which emphasize a difference between variance in case of tensile strength of three stainless steel grades and glass epoxy composite. The main goal is mathematical modeling of those distributions and finding of equations which predict the probability of failure for a sample subjected to a specific stress.
In this paper is presented a comparative study regarding the synthesis of hydroxyapatite powders. The chosen method of synthesis of this biomaterial was chemical co-precipitation. The structure, size and morphology of the obtained powders were analyzed by X-ray diffraction, infrared spectroscopy - FTIR, dynamic light diffusion DLS tehnique and scanning electron microscopy-SEM. The results obtained were compared with those obtained on a commercial hydroxyapatite powder. Investigation methods have confirmed the synthesis of a high purity hydroxyapatite with a optimal degree of crystallization and crystallinity for the reconstruction and regeneration of hard tissue.
The aim of the paper was to develop a device (“pin-on-disc” type) for the measurement of friction in plane friction couplings with sliding movement. On tribometric device (made in our laboratory) we can measure the friction force, friction coefficient and wear, for different loading conditions, speeds, time and material coupling.
For the measurement of the frictional force as well as of the coefficients of friction, mainly the method with a resistive tensiometric transducer is used. With a DataQ DI 245 data acquisition board it is possible to record up to 2 kHz frequencies in the range of -10 ÷ +10 mV with a resolution of 13 bits. To test the functionality of the device, a preliminary test was carried out for a steel pin- on- cast iron disc, for different values of the normal pushing force. The device was calibrated and the measurement results were recorded and processed on the computer.