다중혈관 관상동맥 환자에서 y-문합을 이용하여 양쪽 내흉동맥만을 사용한 우회술의 조기 성적

Human tissue is structured mainly of self-assembled polymers (proteins) and ceramics (bone minerals), with metals present as trace elements with molecular scale functions. However, metals and their alloys have played a predominant role as structural biomaterials in reconstructive surgery, especially orthopedics, with more recent uses in non-osseous tissues, such as blood vessels. With the successful routine use of a large variety of metal implants clinically, issues associated with long-term maintenance of implant integrity have also emerged. This review focuses on metallic implant biomaterials, identifying and discussing critical issues in their clinical applications, including the systemic toxicity of released metal ions due to corrosion, fatigue failure of structural components due to repeated loading, and wearing of joint replacements due to movement. This is followed by detailed reviews on specific metallic biomaterials made from stainless steels, alloys of cobalt, titanium and magnesium, as well as shape memory alloys of nickel–titanium, silver, tantalum and zirconium. For each, the properties that affect biocompatibility and mechanical integrity (especially corrosion fatigue) are discussed in detail. Finally, the most critical challenges for metallic implant biomaterials are summarized, with emphasis on the most promising approaches and strategies.

Metallic implant biomaterials

https://www.tpbin.com/Uploads/Subjects/643149a0-8194-4c67-bf05-73fae6f0d14f.pdf

Development of new metallic alloys for biomedical applications

Young's modulus as well as tensile strength, ductility, fatigue life, fretting fatigue life, wear properties, functionalities, etc., should be adjusted to levels that are suitable for structural biomaterials used in implants that replace hard tissue. These factors may be collectively referred to as mechanical biocompatibilities. In this paper, the following are described with regard to biomedical applications of titanium alloys: the Young's modulus, wear properties, notch fatigue strength, fatigue behaviour on relation to ageing treatment, improvement of fatigue strength, fatigue crack propagation resistance and ductility by the deformation-induced martensitic transformation of the unstable beta phase, and multifunctional deformation behaviours of titanium alloys.

Mechanical biocompatibilities of titanium alloys for biomedical applications.

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Binary titanium alloys containing Nb or Ta, which are allergy-free and non-toxicity elements, were fabricated, and then the possibility of their application to various music instruments made of brass was investigated by the evaluation of corrosion characteristics, elastic modulus-density ratio (E/ρ), resonance frequency (f) and internal friction (Q−1) . The practical models of the mouthpieces of the trumpets made of the binary titanium alloys were also fabricated by precision casting method in order to compare directly with the sound characteristics of those made of brass and commercially pure Ti. The critical current density for the passivation of the Ti–Nb and Ti–Ta system alloys is approximately 40% lower than that of brass and nearly equal to or a little higher than that of commercially pure Ti. The Q−1 of the Ti–Nb and Ti–Ta system alloys with α″ phase drastically increase. The E/ρ and f of the Ti–Nb and Ti–Ta system alloys exhibit a positive relationship. The sound characteristics of practical mouthpieces of trumpets for a bass instrument can be controlled by changing the E/ρ and f of the alloys.

Development of allergy-free titanium alloys for brass instruments and their characteristics

1Faculty of Science and Engineering, Kindai University, Higashiosaka 577–8502, Japan 2Institute for Materials Research, Tohoku University, Sendai 980–8577, Japan 3Graduate School of Engineering, Osaka University, Osaka 565–0871, Japan 4Graduate School of Science and Technology, Meijyo University, Nagoya 468–8502, Japan 5Institute of Materials and Systems for Sustainability, Nagoya University, Nagoya 464–8603, Japan 6Joining and Welding Research Institute, Osaka University, Ibaraki 567–0047, Japan 7Aerospace Company, Kawasaki Heavy Industries, Ltd., Kakamigahara 504–8710, Japan

Heat Treatment to Improve Fatigue Strength of Friction Stir Welded Ti-6Al-4V Alloy Butt Joint

Titanium (Ti) and its alloys are currently getting much attention for structural biomaterials, because they are much advantageous as compared with other metallic biomaterials such as biomedical stainless steels and Co-based alloys, and their practical uses in implant devices are widely spreading. In this paper, types of Ti alloys for biomedical applications are first described. Pure Ti, (α + β)-type, and β-type Ti alloys for biomedical applications including general β-type Ti alloys, superelastic and shape-memory β-type Ti alloys, Young’s modulus self-adjustable β-type Ti alloys, and β-type Ti alloys for reconstructive implants are then described.

Ti-Based Biomedical Alloys

Quantitative and Qualitative Relationship between Microstructural Factors and Fatigue Lives under Load- and Strain-Controlled Conditions of Ti–5Al–2Sn–2Zr–4Cr–4Mo (Ti-17) Fabricated Using a 1500-ton Forging Simulator

Masaaki Nakai

Papers

Development of allergy-free titanium alloys for brass instruments and their characteristics

Heat Treatment to Improve Fatigue Strength of Friction Stir Welded Ti-6Al-4V Alloy Butt Joint

Ti-Based Biomedical Alloys

Quantitative and Qualitative Relationship between Microstructural Factors and Fatigue Lives under Load- and Strain-Controlled Conditions of Ti–5Al–2Sn–2Zr–4Cr–4Mo (Ti-17) Fabricated Using a 1500-ton Forging Simulator

Change in Mechanical Properties of Biomechanical Ti-12Cr Subjected to Heat Treatment and Surface Modification Processing