Download or read book Development of a Hydroxyapatite Coating on AZ31 Magnesium Alloy for Use in Biodegradable Implants written by Madila Awalini and published by . This book was released on 2015 with total page 378 pages. Available in PDF, EPUB and Kindle. Book excerpt: Known to have poor corrosion resistance for general engineering applications, magnesium alloys have recently attracted great interest among researchers for use as biodegradable osteo-implants. The extremely low corrosion resistance of these alloys, which has been a major drawback for its use as light-weight surgical implants, is an advantage point for the application of biodegradable implants. Ideally, biodegradable implants should have a controllable dissolution rate, or in other words, a delayed corrosion reaction on its surface to maintain mechanical integrity until the bone restores itself. Thereafter, the implant should be degraded over time in a controlled manner and reabsorbed safely into the body as the healing process is completed – so that no secondary surgery is needed to remove the implants. The main challenge in this research work is to investigate an approach of improving corrosion resistance of AZ31 Magnesium alloy, by introducing a corrosion-rate controlling layer between the implant material and the body fluid. This research work explores the use of plasma spray as the deposition method for applying the hydroxyapatite (HAp) coatings on AZ31 substrates. The spray parameters used in all trials have successfully led to production of a porous coating structure specifically designed for corrosion-rate controlling layer for biodegradable implants. Corrosion-tested samples were characterised to evaluate their degradation behaviour to establish an understanding of the corrosion mechanism of the designed coating system in this work. An improved corrosion resistance has been achieved by applying a plasma-sprayed HAp coating on bare AZ31 material, in which the corrosion rate is slower than that of uncoated material. Additionally, the carbonate treatment of the HAp-coated AZ31 has successfully enhanced the corrosion characteristic of the designed coating system. Despite the fact that AZ31 is corroding due to the presence of corrosive medium at the substrate-coating interface area, the coating is still adherent to allow a controlled degradation mechanism - thus preventing a catastrophic failure of the designed coating system.

Download or read book Surface Modification of Magnesium and its Alloys for Biomedical Applications written by T.S.N. Sankara Narayanan and published by Elsevier. This book was released on 2015-01-30 with total page 461 pages. Available in PDF, EPUB and Kindle. Book excerpt: The development of biodegradable implants which can remain in the human body to fix a problem and subsequently dissolve, or be absorbed, consumed or excreted, without warranting a secondary surgery, is very appealing to scientists. Due to their excellent biocompatibility and biodegradability, magnesium implants provide a viable option many problems associated with permanent metallic implants such as, restenosis, thrombosis, permanent physical irritation, and inability to adapt to growth and changes in human body. Volume 2 of this important new book explores practical issues of magnesium and magnesium alloys, physical and mechanical modification and coatings to enhance this material for biomedical applications. Includes expert analysis on chemical solution deposition of hydroxyapatite (HAp) and octacalcium (OCP) phosphate coatings for magnesium Comprehensive coverage of biomimetic modifications, surface functionalization of biomolecules, natural, conducting and biodegradable polymeric coatings Lucid dissection of chemical, physical, mechanical and electromechanical modifications of magnesium and its alloys for biomedical applications

Download or read book Hydroxyapatite HAp for Biomedical Applications written by Michael Mucalo and published by Elsevier. This book was released on 2015-03-06 with total page 402 pages. Available in PDF, EPUB and Kindle. Book excerpt: Hydroxyapatite in the form of hydroxycarbonate apatite is the principal mineral component of bone tissue in mammals. In Bioceramics, it is classed as a bioactive material, which means bone tissue grows directly on it when placed in apposition without intervening fibrous tissue. Hydroxyapatite is hence commonly used as bone grafts, fillers and as coatings for metal implants. This important book provides an overview of the most recent research and developments involving hydroxyapatite as a key material in medicine and its application. - Reviews the important properties of hydroxyapatite as a biomaterial - Considers a range of specific forms of the material and their advantages - Reviews a range of specific medical applications for this important material

Download or read book Fabrication of Hydroxyapatite Coated Magnesium Alloy for Orthopedic Bio degradable Metallic Implant Applications written by Sai Abhishek Arshanapalli and published by . This book was released on 2013 with total page 85 pages. Available in PDF, EPUB and Kindle. Book excerpt: Magnesium (Mg) and its alloys are potential biodegradable implant materials because of their alluring biological property. Moreover, they have attracted growing interest as a promising alternative for medical implant and device applications due to their advantageous mechanical and biological properties. However, the major limitation of magnesium is its rapid degradation in physiological fluids and low corrosion resistance property which might lead to failure of implants. Therefore, the present key challenge lies in controlling Mg degradation rate in physiological environment. The objective of this thesis was to fabricate Hydroxyapatite on magnesium alloy for orthopedic biodegradable implant operations. Hydroxyapatite (HA) is a calcium phosphate bio ceramic material that has nearly identical properties to that of the mineral component of bone. Its osteoconductivity and biocompatibility have led to its application in a broad range of applications in orthopedics and dentistry. The present work aims to deposit Hydroxyapatite (HA) on magnesium AZ31using electrode position technique to enhance the bio-degradable property of magnesium implant material. The morphology of the coatings were studied using SEM-EDS and FTIR characterizations and optical microscopy. The biodegradable nature of HA coatings were examined by electrochemical tests. Post treatment of HA coating is required to convert the amorphous phases into complete HA. The experimental results signified that HA coatings after post treatment in alkali solution 1M NaOH can slowdown the biodegradation rate of AZ31 magnesium alloy in Phosphate Buffered Saline (PBS).

Download or read book Plasma Electrolytic Oxidation PEO Coatings written by Marta Mohedano and published by MDPI. This book was released on 2021-06-02 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt: Plasma electrolytic oxidation (PEO), also known as micro-arc oxidation (MAO), functionalizes surfaces, improving the mechanical, thermal, and corrosion performance of metallic substrates, along with other tailored properties (e.g., biocompatibility, catalysis, antibacterial response, self-lubrication, etc.). The extensive field of applications of this technique ranges from structural components, in particular, in the transport sector, to more advanced fields, such as bioengineering. The present Special Issue covers the latest advances in PEO‐coated light alloys for structural (Al, Mg) and biomedical applications (Ti, Mg), with 10 research papers and 1 review from leading research groups around the world.

Download or read book Recent Developments of Electrodeposition Coating written by Andrzej Zieliński and published by MDPI. This book was released on 2021-08-31 with total page 176 pages. Available in PDF, EPUB and Kindle. Book excerpt: This e-book presents a selection of papers focused on some novel aspects of electrodeposited coatings, in particular for medical applications. The biocoatings applied for surface modification of load-bearing implants are still being developed, especially for titanium implants, for which hundreds and thousands of possible technical solutions have been proposed using different techniques and materials. This book is a collection of papers that demonstrate appropriate attempts using various electrodeposition methods. The specific objectives are different, with several looking for improved bioactivity, another for antibacterial properties, and another for increased adhesion on the helix lines on dental implants. The e-book starts with a paper on the methodic development of electrodes for electrowinning. This is followed by paper on the real performance of the surface of dental implants, a subject not often addressed. The next paper focuses on electro-oxidation: a novel two-stage oxidation method, characteristic of the oxide layer on helix line of a model dental implant, and micro-arc oxidation of 3D printed titanium. The last paper focuses on coatings, describing the carbon nanotubes- (hydroxyapatite, chitosan), Eudragit-, and Fe-containing coatings. The e-book concludes with a review of all electrodeposition methods. It is a collection of papers describing novel results in electrodeposition biocoatings, which will be of interest for many scholars and researchers.

Download or read book Surface Modification of Magnesium and its Alloys for Biomedical Applications written by T.S.N. Sankara Narayanan and published by Elsevier. This book was released on 2015-01-08 with total page 381 pages. Available in PDF, EPUB and Kindle. Book excerpt: Surface modification of magnesium and its alloys for biomedical applications: Biological interactions, mechanical properties and testing, the first of two volumes, is an essential guide on the use of magnesium as a degradable implant material. Due to their excellent biocompatibility and biodegradability, magnesium based degradable implants provide a viable option for the permanent metallic implants. This volume focuses on the fundamental concepts of surface modification of magnesium, its biological interactions, mechanical properties and, in vitro and in vivo testing. The contents of volume 1 is organized and presented in three parts. Part 1 reviews the fundamental aspects of surface modification of magnesium, including surface design, opportunities, challenges and its role in revolutionizing biodegradable biomaterials. Part 2 addresses the biological and mechanical properties covering an in vivo approach to the bioabsorbable behavior of magnesium alloys, mechanical integrity and, the effects of amino acids and proteins on the performance of surface modified magnesium. Part 3 delves in to testing and characterization, exploring the biocompatibility and effects on fatigue life alongside the primary characteristics of surface modified magnesium. All chapters are written by experts, this two volume series provides systematic and thorough coverage of all major modification technologies and coating types of magnesium and its alloys for biomedical applications. - Expert analysis of the fundamentals in surface modification of magnesium and its alloys for biomedical applications - Includes biological interactions and mechanical properties - Focuses on testing and characterisation, as well as biocompatibility

Download or read book Surface Modification of Biodegradable Magnesium Implant Materials for Controlled Biodegradation written by Afrah Al Hegy and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Magnesium and its alloys are promising candidates to be employed as a new generation of biodegradable metals in orthopaedic applications. However, the rapid degradation rate of magnesium alloys in the physiological environment has prevented their widespread application in medicine. The main objective of this thesis was to develop surface modification strategies that control the degradation rate of magnesium alloys in physiological environments and to provide an accurate assessment and evaluation of their biocompatibility in vitro. The overall thesis is composed of three individual projects. The first project was to develop an accurate method to test the in vitro biocompatibility of magnesium alloys. In this study, the CyQUANT assay was used to quantitatively evaluate the in vitro biocompatibility of Mg AZ31 alloy by both direct and indirect methods. The results demonstrated that the CyQUANT assay provides a more complete assessment of the overall in vitro biocompatibility of biodegradable metals by combining both direct and indirect analyses. In the second project, a multilayer coating consisting of a sol-gel silica layer followed by a mesoporous silica layer and finally a layer of calcium phosphate was developed. Surface characterization showed that a uniform and stable multilayer coating was successfully deposited on the Mg AZ31 alloy. In vitro characterization of the coatings confirmed this surface modification strategy significantly decreases the degradation rate of the magnesium alloy and that it is not cytotoxic. Superhydrophobic surfaces decrease the corrosion rate of magnesium alloys, however, cell adhesion is inhibited. In the third project, a superhydrophobic magnesium alloy surface was modified with the cell adhesive molecule, MAPTrix-F-RGD and the influence of this surface modification on cell adhesion was studied. The results demonstrate that although the MAPTrixF-RGD molecule was successfully immobilized to the superhydrophobic magnesium alloy surface, cell adhesion was not improved. The complex surface topography of the superhydrophobic Mg AZ31 surface may be responsible for the observed cell behavior. This thesis demonstrates that surface modification can be used to simultaneously control both the biodegradation rate and the biocompatibility of magnesium and its alloys, making these materials promising candidates for orthopaedic applications. In addition, it has been demonstrated that cell quantification assays based on the fluorescence of cyanine dyes are an excellent method for in vitro testing of these materials in direct contact with cells.

Download or read book Magnesium Biomaterials written by Nicholas Travis Kirkland and published by Springer Science & Business Media. This book was released on 2013-10-12 with total page 142 pages. Available in PDF, EPUB and Kindle. Book excerpt: Magnesium Biomaterials provides a succinct up-to-date overview of Magnesium biomaterial development, critically examines the types of in vitro experiments that may be performed, and investigates the numerous variables that affect Magnesium biodegradation when undertaking these experiments. This work also discusses the direction in which current Magnesium biomaterial development is heading and the necessary steps for future development of this field. Information is drawn from numerous multi-disciplinary sources to provide a coherent and critical overview. Magnesium Biomaterials is ideal for researchers in the area of bio-Mg, companies interested in exploring their own alloys, and for researchers working with other biodegradable materials who are seeking a cross-platform understanding of material performance.

Download or read book Development of Silane Based Coating for Corrosion Protection of Magnesium Alloy for Biomedical Implant Application written by Swati Gaur and published by . This book was released on 2015 with total page 354 pages. Available in PDF, EPUB and Kindle. Book excerpt: Biomaterials are used in several medical applications today, such as fixation devices,replacements and surgical equipment. Implants are typical examples of a biomaterial application and there are several different implant materials used today. Conventional implant materialsinclude stainless steels, cobalt-chromium alloys, alumina, polymers (methyl methacrylate), polyethylene etc. There are several impediments associated with long term presence of implants inside body, including allergy and sensitization. After the healing and curing, the implant isremoved by a second surgery which is not only costly but also very painful. To make this process simpler, less painful and cost effective, there is a need for alternative methodology, called the use of temporary biodegradable implants. The purpose of biodegradable implant is to support tissueregeneration and healing by material degradation and simultaneous implant replacement through the surrounding tissues. In recent years there has been increased amount of focus on magnesium and its alloys for their potential use as biodegradable implant materials. Magnesium isbiocompatible; has excellent mechanical properties; is natural for human body, and seems to stimulate new bone formation. However, a serious problem with magnesium is its high corrosion rate with consistent hydrogen gas formation which delays the healing process. Hence, there is need for controlling their degradation rate, by some surface modification.In this research work magnesium based alloy system containing calcium and zinc wasinvestigated (Mg-6Zn-Ca alloy) which are supposed to be non-toxic in the body. The work focused on to mitigate/delay the corrosion rate of the alloy by development of silane based coating systems for effective corrosion resistance and selecting the coating chemistry to providebiocompatibility. Two different types of silane based coating systems were studied anddeveloped. Phosphonato silane approach (DEPETES with MTEOS and BTESPT as precursor)and non-Phosphonato silanes approach (GPTMS with MTEOS) were used to develop coating.As developed coatings were subjected to various detailed characterization techniques like, scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDAX) and the cross-linking in the coating was studied using Fourier transform infrared spectroscopy (FTIR)and performance evaluation, using Electrochemical Impedance Spectroscopy (EIS), Potentiodynamic polarization, hydrogen evolution and pH change. Further, biological responseof human osteoblast cell line on the developed coating system was studied. The in vitro cytotoxicity studies were performed on human osteoblast cells MG-63 to observe cellmorphology, attachment, proliferation and differentiation. It was found that the silane coated alloy shows an improved corrosion resistance and biocompatibility as compared to bare Mg-6Zn-Ca alloy.

Download or read book Bioceramic Coatings for Medical Implants written by Robert B. Heimann and published by John Wiley & Sons. This book was released on 2015-03-10 with total page 493 pages. Available in PDF, EPUB and Kindle. Book excerpt: Reflecting the progress in recent years, this book provides in-depth information on the preparation, chemistry, and engineering of bioceramic coatings for medical implants. It is authored by two renowned experts with over 30 years of experience in industry and academia, who know the potentials and pitfalls of the techniques concerned. Following an introduction to the principles of biocompatibility, they present the structures and properties of various bioceramics from alumina to zirconia. The main part of the work focuses on coating technologies, such as chemical vapor deposition, sol-gel deposition and thermal spraying. There then follows a discussion of the major interactions of bioceramics with bone or tissue cells, complemented by an overview of the in-vitro testing methods of the biomineralization properties of bioceramics. The text is rounded off by chapters on the functionalization of bioceramic coatings and a look at future trends. As a result, the authors bring together all aspects of the latest techniques for designing, depositing, testing, and implementing improved and novel bioceramic coating compositions, providing a full yet concise overview for beginners and professionals.

Download or read book Hydroxyapatite Coatings for Biomedical Applications written by Sam Zhang and published by CRC Press. This book was released on 2013-05-14 with total page 473 pages. Available in PDF, EPUB and Kindle. Book excerpt: Hydroxyapatite coatings are of great importance in the biological and biomedical coatings fields, especially in the current era of nanotechnology and bioapplications. With a bonelike structure that promotes osseointegration, hydroxyapatite coating can be applied to otherwise bioinactive implants to make their surface bioactive, thus achieving faster healing and recovery. In addition to applications in orthopedic and dental implants, this coating can also be used in drug delivery. Hydroxyapatite Coatings for Biomedical Applications explores developments in the processing and property characterization and applications of hydroxyapatite to provide timely information for active researchers and newcomers alike. In eight carefully reviewed chapters, hydroxyapatite experts from the United States, Japan, Singapore, and China present the latest on topics ranging from deposition processes to biomedical applications in implants and drug delivery. This book discusses: Magnetron sputtering and electrochemical deposition The modification of hydroxyapatite properties by sol–gel deposition to incorporate other elements found in natural bones, such as zinc, magnesium, and fluorine The use of pure hydroxyapatite in drug delivery applications The growth or self-assembly of hydroxyapatite on shape memory alloy Hydroxyapatite composite coatings—with carbon nanotubes, titanium dioxide (TiO2), and others—on the titanium alloy Offering valuable insights and a wealth of data, including numerous tables and figures, this is a rich source of information for research on hydroxyapatite coatings. Each chapter also covers material that provides an accessible stepping stone for those who are new to the field.

Download or read book Sol Gel Science written by C. Jeffrey Brinker and published by Academic Press. This book was released on 2013-10-22 with total page 925 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sol-Gel Science: The Physics and Chemistry of Sol-Gel Processing presents the physical and chemical principles of the sol-gel process. The book emphasizes the science behind sol-gel processing with a chapter devoted to applications. The first chapter introduces basic terminology, provides a brief historical sketch, and identifies some excellent texts for background reading. Chapters 2 and 3 discuss the mechanisms of hydrolysis and condensation for nonsilicate and silicate systems. Chapter 4 deals with stabilization and gelation of sols. Chapter 5 reviews theories of gelation and examines the predicted and observed changes in the properties of a sol in the vicinity of the gel point. Chapter 6 describes the changes in structure and properties that occur during aging of a gel in its pore liquor (or some other liquid). The discussion of drying is divided into two parts, with the theory concentrated in Chapter 7 and the phenomenology in Chapter 8. The structure of dried gels is explored in Chapter 9. Chapter 10 shows the possibility of using the gel as a substrate for chemical reactions or of modifying the bulk composition of the resulting ceramic by performing a surface reaction (such as nitridation) on the gel. Chapter 11 reviews the theory and practice of sintering, describing the mechanisms that govern densification of amorphous and crystalline materials, and showing the advantages of avoiding crystallization before sintering is complete. The properties of gel-derived and conventional ceramics are discussed in Chapter 12. The preparation of films is such an important aspect of sol-gel technology that the fundamentals of film formation are treated at length in Chapter 13. Films and other applications are briefly reviewed in Chapter 14. Materials scientists and researchers in the field of sol-gel processing will find the book invaluable.

Download or read book Advances in Corrosion Control of Magnesium and its Alloys written by Viswanathan S. Saji and published by CRC Press. This book was released on 2023-08-22 with total page 471 pages. Available in PDF, EPUB and Kindle. Book excerpt: Magnesium (Mg) and its alloys have received widespread acceptance in automobile industries and biomedical applications with substantial recent advancements made in their development, however a significant limitation remains their poor aqueous and galvanic corrosion resistance. This book covers both the fundamentals and recent advancements in two major corrosion protection strategies of magnesium and its alloys, namely, metal-matrix composites and protective coatings. Key features: Covers all aspects of metal-matrix composites and protective coatings for magnesium alloys to improve their corrosion resistance, wear resistance, mechanical properties and biocompatibility Provides the most recent research advancements in the corrosion mitigation strategies of magnesium and its alloys Complete with case studies specific to practical applications, this book serves as a ready reference for graduate students, researchers, engineers and industry professionals in the fields of materials, corrosion science, biofouling and protective coatings.

Download or read book Conversion Coatings for Magnesium and its Alloys written by Viswanathan S. Saji and published by Springer Nature. This book was released on 2022-02-01 with total page 577 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book covers fundamentals and recent advancements on conversion coatings for magnesium and its alloys. The contents are presented in two sections, respectively dealing with chemical and electrochemical conversion coatings. The chemical conversion coating section is further subdivided into inorganic conversion coatings, organic conversion coatings and advanced approaches/coatings. The section on electrochemical conversion coatings spans from fundamentals to state-of-the-art progress on electrochemical anodization and plasma electrolytic oxidation of magnesium and its alloys.

Download or read book Advances in Corrosion Control of Magnesium and its Alloys written by Viswanathan S. Saji and published by CRC Press. This book was released on 2023-08-22 with total page 631 pages. Available in PDF, EPUB and Kindle. Book excerpt: Magnesium (Mg) and its alloys have received widespread acceptance in automobile industries and biomedical applications with substantial recent advancements made in their development, however a significant limitation remains their poor aqueous and galvanic corrosion resistance. This book covers both the fundamentals and recent advancements in two major corrosion protection strategies of magnesium and its alloys, namely, metal-matrix composites and protective coatings. Key features: Covers all aspects of metal-matrix composites and protective coatings for magnesium alloys to improve their corrosion resistance, wear resistance, mechanical properties and biocompatibility Provides the most recent research advancements in the corrosion mitigation strategies of magnesium and its alloys Complete with case studies specific to practical applications, this book serves as a ready reference for graduate students, researchers, engineers and industry professionals in the fields of materials, corrosion science, biofouling and protective coatings.

Download or read book Magnesium Alloys as Degradable Biomaterials written by Yufeng Zheng and published by CRC Press. This book was released on 2015-10-09 with total page 601 pages. Available in PDF, EPUB and Kindle. Book excerpt: Magnesium Alloys as Degradable Biomaterials provides a comprehensive review of the biomedical applications of biodegradable magnesium and its alloys. Magnesium has seen increasing use in orthopedic and cardiovascular applications over the last decade, particularly for coronary stents and bone implants.The book discusses the basic concepts of biodeg