Study on Biomedical Porous Ti-6Al-4V Alloy Fabricated by Electron Beam Selective Melting

Biomedical porous Ti-6Al-4V alloys were fabricated by electron beam melting. The effects of process setting and porous structure on the microstructrue and mechanical properties of the alloy were studied. The result shows that micropores at the surface of macropores wall could be obtained using lower temperature, lower beam intensity and higher sanning speed during the forming process. Compared with traditiorial porous materials, such double-peak pore structure not only benefits to the bone growth but also decreases the modulus effectively. The tiny melting pool during the electron beam melting could lead to a rapid cooling speed which can promote beta ->alpha ' phase transformation and form fine acicular microstructure. Cell unit similar to bone structrure with smoth internal wall and no acute angle is sutable for biomedical implant, and the modulus decreases with increase of the porosity, which can reach the real bone structure. The relationship between the relative modulus and relative density is E=E-0(rho/rho(0))(0.79).