title: Surface modification of investment cast-316L implants: microstructure effects.
abstract: Artificial femur stem of 316L stainless steel was fabricated by investment casting using vacuum induction melting. Different surface treatments: mechanical polishing, thermal oxidation and immersion in alkaline solution were applied. Thicker hydroxyapatite (HAP) layer was formed in the furnace-oxidized samples as compared to the mechanically polished ones. The alkaline treatment enhanced the precipitation of HAP on the samples. It was also observed that the HAP precipitation responded differently to the different phases of the microstructure. The austenite phase was observed to have more homogeneous and smoother layer of HAP. In addition, the growth of HAP was sometimes favored on the austenite phase rather than on ferrite phase.
authors.affiliation: Central Metallurgical Research & Development Institute, P.O. Box 87, Helwan, Cairo, Egypt. Electronic address: shimaam@cmrdi.sci.eg.
authors.forename: Shimaa
authors.initials: S
authors.lastname: El-Hadad
authors.affiliation: Cairo University, Faculty of Engineering, Dept. of Mining, Petroleum and Metallurgical Engineering, 12613 Giza, Egypt. Electronic address: wkhalifa@eng.cu.edu.eg.
authors.forename: Waleed
authors.initials: W
authors.lastname: Khalifa
authors.affiliation: Central Metallurgical Research & Development Institute, P.O. Box 87, Helwan, Cairo, Egypt. Electronic address: adelnofal@cmrdi.sci.eg.
authors.forename: Adel
authors.initials: A
authors.lastname: Nofal
mesh_terms: D020099:Coated Materials, Biocompatible; D017886:Durapatite; D005269:Femur; D006801:Humans; D019736:Prostheses and Implants; D013193:Stainless Steel
chemical_list: D020099:Coated Materials, Biocompatible; D013193:Stainless Steel; D017886:Durapatite
keywords: Hydroxyapatite; Investment casting; Stainless steel; Surface modification