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Naci Kurgan - One of the best experts on this subject based on the ideXlab platform.

  • effect of porosity and density on the mechanical and microstructural properties of sintered 316l Stainless Steel Implant materials
    Materials & Design, 2014
    Co-Authors: Naci Kurgan
    Abstract:

    Abstract In this study, the microstructure and mechanical properties of sintered AISI 316L Stainless Steel Implant materials produced by powder metallurgy (P/M) method were investigated as a function of porosity amount. AISI 316L Stainless Steel powders were cold-pressed with 800 MPa pressure and sintered at 1200 °C, 1250 °C and 1300 °C for 30 min in a nitrogen atmosphere. The mechanical properties of the 316L Implant samples were determined by tensile, fatigue and microhardness tests. Metallographic studies such as pore formation, and fractured surface analyses were performed by Scanning Electron Microscopy (SEM) and Light Optical Microscopy (LOM). The results of this study indicate that, irregular pore formation tendencies increase with an increase in porosity (%). Furthermore, an increase in porosity was shown to decrease the mechanical properties of sintered AISI 316L Stainless Steel. Sintering temperature is important parameter in decreasing the porosity of P/M materials.

  • production of 316l Stainless Steel Implant materials by powder metallurgy and investigation of their wear properties
    Chinese Science Bulletin, 2012
    Co-Authors: Naci Kurgan, Yavuz Sun, Bunyamin Cicek, Hayrettin Ahlatci
    Abstract:

    In this study, the mechanical and wear properties of AISI 316L Stainless Steel Implant materials, produced by powder metallurgy (P/M), were investigated. AISI 316L Stainless Steel powder was cold-pressed with 800 MPa of pressure and then sintered at 1200, 1250 and 1300°C for 30 min as three sample groups. The microstructure, and mechanical and wear properties of the resulting Steels were investigated. Light optical and scanning electron microscopiese were used to characterize the microstructure of the Steels. Room temperature mechanical properties of the Steels were determined by hardness measurements and impact tests. Wear was determined using the pin-on-disc wear test, and the results were evaluated according to weight loss. The results indicate that the sintering temperature, time and atmosphere are important parameters that affect the porous ratio of materials produced by P/M. Sintering at high temperature can eliminate small pores and make the residual pores spherical. The wear tests showed that the wear of the AISI 316L Stainless Steel Implants changed depending on the sintering temperature and load. Spherical pores in the samples increase the wear resistance. Moreover, decreasing the porosity ratio of these materials improves all of their mechanical properties.

R D K Misra - One of the best experts on this subject based on the ideXlab platform.

  • biomimetic nanostructured hydroxyapatite coatings on metallic Implant materials
    Materials Technology, 2016
    Co-Authors: Sachin A Mali, K C Nune, R D K Misra
    Abstract:

    Metallic Implant materials used in load-bearing applications are inert in nature in their native state. The surface properties of the material and its interaction with the surrounding physiological fluid determine the success of the biomedical Implant. In this regard, bioactive nanostructured coatings are being recognised as potential approach to enhance the biological and corrosion properties of the conventional inert materials. In this review, recent advances in biomedical applications of nanostructured hydroxyapatite coatings on Stainless Steel Implant materials are highlighted with special focus on the electrochemical deposition of hydroxyapatite and their consequent biological activity. Furthermore, osteoblasts functions and cellular activity on the nanostructured hydroxyapatite coatings processed by other techniques is also discussed. The potential application of such next generation materials as biomedical Implants is also addressed.

  • pre adsorption of protein on electrochemically grooved nanostructured Stainless Steel Implant and relationship to cellular activity
    Journal of Biomedical Nanotechnology, 2014
    Co-Authors: K C Nune, R D K Misra
    Abstract:

    : The successful integration of a biomedical device is governed by the surface properties of the material and also depends on the interaction with the physiological fluid involving adsorption of proteins on the surface. Pre-adsorbed proteins act as pilots for cell adhesion and subsequently govern cellular activity. In this regard, nanograined materials are excellent vehicles to obtain an unambiguous understanding of protein adsorption, which regulate cell adhesion and cellular activity. Toward this end, we have used the concept of phase reversion-induced nanograined structure to understand grain structure-induced self-assembly of a model protein, bovine serum albumin. Furthermore, in the context of bio-mechanical interlocking between Implant and bone, and osseointegration of the Implant, grain boundaries were electrochemically grooved and studied for osteoblast functions. Experiments indicated that the significant differences in cell attachment, proliferation, and expression level of prominent proteins (actin, vinculin, and fibronectin) is related to synergistic effects of grain structure, pre-adsorbed protein, and grooving of grain boundaries such that the osteoblasts functions and cellular activity is promoted on the nanostructured surface in relation to the coarse-grained counterpart.

Mohammadhossein Fathi - One of the best experts on this subject based on the ideXlab platform.

  • Effect of Surface Treatment and Metallic Coating on Corrosion Behavior and Biocompatibility of Surgical 316L Stainless Steel Implant
    Journal of Materials Science & Technology, 2012
    Co-Authors: Ali Parsapour, Saied Nouri Khorasani, Mohammadhossein Fathi
    Abstract:

    Surface engineering technology is a suitable method for coatings on the metal surfaces or performing surface modification treatment, which can improve corrosion resistance and biocompatibility of metals. In this research, corrosion behavior of Nb coating on H2SO4 and HNO3 treated AISI Stainless Steel 316L (SS) was evaluated. Nb coating was carried out using physical vapor deposition process on the SS. Characterization techniques including scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) technique were used to investigate the microstructure and morphology of the coated and treated SS. Electrochemical potentiodynamic tests were performed in two types of physiological solutions and compared with the pristine SS specimens. Cyclic polarization tests were performed to evaluate resistivity against pitting. Experimental results indicate that Nb coating and surface treatment of the SS had a positive effect on improvement of corrosion behavior. The decrease in corrosion current densities was significant for coated and treated specimens. The corrosion current density was much lower than the values obtained for pristine specimens.

Martanto, Tri Wahyu - One of the best experts on this subject based on the ideXlab platform.

  • Uji Biokompabilitas pada Implan Orthopedi Antara Implan Impor, Implan Lokal dari Material Impor, dan Prototipe Stainless Steel 316L dari Material Lokal
    'Universitas Muhammadiyah Surabaya', 2019
    Co-Authors: Mahyudin Ferdiansyah, Waskita, Heppy Chandra, Utomo, Dwikora Novembri, Suroto Heri, Martanto, Tri Wahyu
    Abstract:

    ABSTRACT  Demands of orthopedic Implants are increasing in Indonesia, but its production are limited and still imported. Stainless Steel, especially 316L is one of metal that is used commonly. This research evaluates biocompatibility of Stainless Steel 316L Implant prototype, local Implant manufactured using imported Stainless Steel, and imported Stainless Steel Implant. Cytotoxicity test used mesenchymal human cell with MTT assay. Irritation test, acute toxicity/pyrogenicity test, and Implantation test used 24 Wistar rats respectively which were assigned to 4 groups. We evaluate Draize score, weight and rectal temperature changes, and fibrous capsule ring thickness. Cytotoxicity test shows viable cell percentage in Stainless Steel 316L Implant prototype, local Implant, and imported Implant are 83.7%, 87.5%, and 83.7% respectively. Comparison test using One Way ANOVA shows no significant difference between 3 groups (p>0.05). Iritation test results in 3 groups are grade 0 (no edema and no erythema). Acute toxicity/pyrogenicity test shows no statistically significant difference (p>0.05) among all groups. There is also no significant difference (p>0.05) of fibrous capsule ring thickness on 1 and 4 weeks after Implantation. Based on ISO for medical test guide, Stainless Steel 316L Implant prototype is safe and has similar biocompatibility test result compared to local and imported Implant.Keywords                   : Stainless Steel 316L, biocompatibility, orthopaedic ImplantCorrespondence to    : ferdiansyah@fk.unair.ac.id ABSTRAKKebutuhan implan orthopedi terus meningkat di Indonesia, namun produksinya terbatas dan sebagian besar masih impor dari luar negeri. Stainless Steel, utama 316L adalah salah satu metal yang sering digunakan. Penelitian ini mengevaluasi biokompatibilitas dari prototipe implan Stainless Steel 316L, implan lokal yang diproduksi menggunakan Stainless Steel impor, dan implan Stainless Steel impor. Uji sitotoksisitas menggunakan sel mesenkim human dengan MTT assay. Uji iritasi, uji pirogenositas, dan uji Implantasi menggunakan 24 tikus Wistar yang terbagi dalam 4 grup. Kami mengevaluasi skor Draize, perubahan berat dan temperatur rektal, dan ketebalan fibrous capsule ring. Uji sitotoksisitas menunjukkan persentase viabilitas sel pada prototipe Stainless Steel 316L, implan lokal, dan implan impor berturut-turut adalah 83,7%; 87,5%; dan 83,7%. Uji komparasi dengan One Way Anova tidak menunjukkan perbedaan signifikan diantara 3 grup (p>0,05). Hasil uji iritasi 3 grup menunjukkan grade 0 (tidak ada edema dan eritema). Uji pirogenositas tidak menunjukkan perbedaan signifikan pada semua grup (p>0,05). Tidak ada perbedaan signifikan (p>0,05) pula pada ketebalan fibrous capsule ring di minggu ke 1 dan 4 setelah Implantasi. Berdasarkan ISO untuk pedoman uji di bidang medis, prototipe Stainless Steel 316L aman dan memiliki kesamaan hasil uji biokompatibilitas bila dibandingkan dengan implan lokal dan impor.Kata kunci              : Stainless Steel 316L, uji biokompatibilitas, implan orthopaediKorespondensi       : ferdiansyah@fk.unair.ac.i

Ali Parsapour - One of the best experts on this subject based on the ideXlab platform.

  • Effect of Surface Treatment and Metallic Coating on Corrosion Behavior and Biocompatibility of Surgical 316L Stainless Steel Implant
    Journal of Materials Science & Technology, 2012
    Co-Authors: Ali Parsapour, Saied Nouri Khorasani, Mohammadhossein Fathi
    Abstract:

    Surface engineering technology is a suitable method for coatings on the metal surfaces or performing surface modification treatment, which can improve corrosion resistance and biocompatibility of metals. In this research, corrosion behavior of Nb coating on H2SO4 and HNO3 treated AISI Stainless Steel 316L (SS) was evaluated. Nb coating was carried out using physical vapor deposition process on the SS. Characterization techniques including scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) technique were used to investigate the microstructure and morphology of the coated and treated SS. Electrochemical potentiodynamic tests were performed in two types of physiological solutions and compared with the pristine SS specimens. Cyclic polarization tests were performed to evaluate resistivity against pitting. Experimental results indicate that Nb coating and surface treatment of the SS had a positive effect on improvement of corrosion behavior. The decrease in corrosion current densities was significant for coated and treated specimens. The corrosion current density was much lower than the values obtained for pristine specimens.

  • the effect of surface treatment on corrosion behavior of surgical 316l Stainless Steel Implant
    international journal of iron and steel society of iran, 2007
    Co-Authors: Ali Parsapour, M H Fathi, M Salehi, A Saatchi, M Mahdikhani
    Abstract:

    The AISI 316 L Stainless Steel (SS) specimens were exposed to passivation surface through two different processes including; holding in 40-vol% HNO3 at temperature of 60 oC for 30 min and 15-vol%H2SO4 at ambient temperature for 1 hour. The corrosion behavior of specimens was evaluated in physiological solutions by electrochemical in vitro tests through linear and Tafel polarization tests. Cyclic polarization tests were performed for investigating of the specimen’s resistance against pitting. Finally, the corrosion resistance of untreated and modified specimens was compared. The results show that the corrosion resistance of 316L SS metallic Implant is increased due to passivation surface treatment.