چكيده به لاتين
Magnesium has found wide applications in the medical and implant industries due to its bone-like properties. Although magnesium and its alloys have less mechanical properties than metals such as stainless steel and titanium alloys, the biodegradability properties of this metal have led to its special application in the manufacture of absorbent implants. On the other hand, the production of magnesium parts with porous structure can increase the rate of bone replacement instead of magnesium absorption implants. Therefore, in this dissertation, porous magnesium parts are fabricated using powder metallurgy method. In this method, magnesium powders are combined with porous powders and compressed into a cylindrical shape using cold compression. Then, in order to remove the dispersing particles, the samples are sintered several times in a furnace and immediately immersed in ethanol to obtain samples with the desired porosity percentage. In order to increase the mechanical properties of porous samples and also to increase their resistance to corrosion, the method of composing magnesium samples with hydroxyapatite particles is used. Also, in order to improve the resistance of porous parts against corrosion, a magnesium fluoride coating has been studied. The results of this study lead to the production of non-porous and porous magnesium parts of 30, 50 and 70%. On all the mentioned samples, corrosion and pressure tests have been performed to improve the mechanical properties of porous parts. To better understand the mechanical properties of porous parts in the body, the samples were subjected to pressure tests before and after contact with the corrosive environment to compare the degree of loss of their mechanical properties. In summary, the use of hydroxyapatite particles in magnesium samples will increase their strength by 25 to 35% in the conditions before and after contact with the corrosive environment. Also, the use of magnesium fluoride coating will reduce corrosion by 60 to 70% in samples with different porosity.
