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THE CONCEPT OF PROBE DETECTOR AND ITS APPLICATION IN GEOMETRIC MODELING

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Journal of Donghua University(English Edition) 1989年第Z1期7卷 86-92页

作者： M.Rajbhandari 秦鹏飞 ab sandvik International Sweden Department of Mechanical Engineering CTU

The concept of′Probe detector′is introduced in this paper with its application in geometricmodeling and *** terms of the concept,the authors derive edge data from the CSG datarepresentation and establish a wireframe... 详细信息

关键词： computer aided design computer aided manufacturing geometric modeling graphics wireframe probe detector

Impact of Biomechanical Forces on Antibiotics Release Kinetics from Hydroxyapatite Coated Surgical Fixation Pins

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Journal of Biomaterials and Nanobiotechnology 2013年第4期4卷 343-350页

作者： Mirjam Lilja Jan H.Sorensen Torben C.Sorensen Maria Astrand Philip Procter Hartwig Steckel Maria Stromme Division for Nanotechnology and Functional Materials Department of Engineering SciencesThe Angstrom LaboratoryUppsala UniversityUppsalaSweden sandvik coromant ab StockholmSweden Department of Pharmaceutics and Biopharmaceutics Christian Albrecht University KielKielGermany Stryker Trauma GmbH SchonkirchenGermany Stryker Trauma AG SelzachSwitzerland School of Engineering and Design Brunel UniversityUxbridgeUK

This work investigates the impact of biomechanical wear and abrasion on the antibiotic release profiles of hydroxyapatite (HA) coated fixation pins during their insertion into synthetic bone. Stainless steel fixation pins are coated with crystalline TiO2 by cathodic arc evaporation forming the bioactive layer for biomimetic deposition of Tobramycin containing HA. Tobramycin is either introduced by co-precipitation during HA formation or by adsorption-loading after HA deposition. The samples containing antibiotics are inserted into bone mimicking polyethylene foam after which the drug release is monitored using high performance liquid chromatography. This analysis shows that HA coating wear and delamination significantly decrease the amount of drug released during initial burst, but only marginally influence the sustained release period. Spalled coating fragments are found to remain within the synthetic bone material structure. The presence of HA within this structure supports the assumption that the local release of Tobramycin is not only expected to eliminate bacteria growth directly at the pin interface but as well at some distance from the implant. Furthermore, no negative effect of gamma sterilization could be observed on the drug release profile. Overall, the observed results demonstrate the feasibility of a multifunctional implant coating that is simultaneously able to locally deliver clinically relevant doses of antibiotics and an HA coating capable of promoting osteoconduction. This is a potentially promising step toward orthopaedic devices that combine good fixation with the ability to treat and prevent post-surgical infections.

关键词： Hydroxyapatite Fixation Pin Tobramycin Coating Wear Drug Release Gamma Sterilization

The Effect of Si-Doping on the Release of Antibiotic from Hydroxyapatite Coatings

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Journal of Biomaterials and Nanobiotechnology 2013年第3期4卷 237-241页

作者： Mirjam Lilja Carl Lindahl Wei Xia Hakan Engqvist Maria Stromme Division for Nanotechnology and Functional Materials The Angstrom LaboratoryDepartment of Engineering SciencesUppsala UniversityUppsalaSweden sandvik coromant ab StockholmSweden Division for Applied Material Science The Angstrom LaboratoryDepartment of Engineering SciencesUppsala UniversityUppsalaSweden BIOMATCELL VINN Excellence Center of Biomaterials and Cell TherapyGothenburgSweden

Herein, we show that incorporation of ions during biomimetic coating deposition may be utilized to tailor the drug loading capacity of hydroxyapatite (HA) coatings. Pure biomimetic HA (HA-B) and Si-doped equivalents (SiHA-B) where deposited by a biomimetic process onto titanium dioxide covered titanium substrates. The antibiotic Cephalothin was incorporated into the coatings by adsorptive loading and the release was studied in-vitro. SiHA-B coatings exhibited superior drug incorporation capacity compared to pure HA-B coatings, resulting in a drug release profile dominated by an initial 10 min burst effect while a more prolonged 10 hour release was observed from HA-B coatings. The results emphasize the possibility to impact the drug release kinetics from implant coatings by selective doping elements and the use of thin, biomimetic HA-coatings as drug delivery vehicles. Functionalizing metal implants with SiHA-B coatings presents an interesting strategy towards creating synergetic effects through ion- and antibiotic release and, hence, contributing both towards preventing post-surgical infections while at the same time enhancing the bone-bonding ability.

关键词： Titanium Dioxide Hydroxyapatite Cephalothin Drug Release Si-Doping

Property and Oxidation Behaviours of (Mo,Cr)Si2 + ZrO2 Composite Produced by Pressure-Less Sintering

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Journal of Materials Science and Chemical Engineering 2016年第7期4卷 15-21页

作者： Yiming Yao Erik Ström Xin-Hai Li Qin Lu Department of Materials and Manufacturing Technology Chalmers University of Technology Gothenburg Sweden Heating Systems Division Sandvik Heating Technology AB Hallstahammar Sweden Material Technology Siemens Industrial Turbomachinery AB Finspong Sweden

A composites of (Mo0.9Cr0.1)Si2 + 15vol% ZrO2 was prepared with powder metallurgy and Pressure- Less Sintering (PLS) method, aiming at applications of high temperature structural materials. Mechanical properties of the composites were assessed with hardness, indentation fracture toughness Kc and KIC tested using SEVNB, flexure strength at room temperature and 1200?C, and isothermal oxidation at 1400?C. The results showed that the native silica oxide and molybdenum-oxides on the silicide feedstock surface were significantly reduced in terms of Cr-alloying. (Mo0.9Cr0.1)Si2 and its composite also exhibited improved sinterability and grain growth, owing to the presence of (Cr, Mo)5Si3 at grain boundaries. Fracture toughness of the composite was increased by a factor of 1.6 to that in the monolithic silicide. Mechanical property of the composite at high temperature was not affected by Cr addition. However, the high temperature oxidation resistance was greatly improved in the (Mo0.9Cr0.1)Si2 + 15vol% ZrO2 compared with the non Cr-alloyed counterpart. The Cr-alloying effects on the microstructure, fracture behaviour, and high temperature oxidation resistance were discussed.

关键词： MoSi2 Composite Fracture Toughness Mechanical Property Microstructure High Temperature Oxidation

In Vivo Evaluation of Functionalized Biomimetic Hydroxyapatite for Local Delivery of Active Agents

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Journal of Biomaterials and Nanobiotechnology 2011年第2期2卷 149-154页

作者： Johan Forsgren Ulrika Brohede Sonya Piskounova Albert Mihranyan Sune Larsson Maria Stromme Hakan Engqvist Department of Engineering Sciences Uppsala UniversityUppsalaSweden sandvik ab StockholmSweden Department of Materials Chemistry Uppsala UniversityUppsalaSweden Department of Orthopaedics Uppsala University HospitalUppsalaSweden

This study was carried out to investigate the biological response in vivo to biomimetic hydroxyapatite implant coatings functionalized with bisphosphonates and bone morphogenetic proteins. The functionalization was carried out by a simple soaking procedure in the operating room immediately prior to surgery. Cylindrical titanium samples with and without coatings were implanted in the distal femoral epiphysis of sheep and retrieved after 6 weeks. The histological analysis proved that all samples were integrated well in the tissue with no signs of intolerance. Fewer osteoclasts were observed in the vicinity of bisphosphonate-functionalized samples and the bone was denser around these samples compared to the other samples. Samples functionalized with bone morphogenetic protein induced more bone/implant contact but showed a more inconsistent outcome with reduced bone density around the samples. This study demonstrates a simple method to functionalize implant coatings, which provides surgeons with an option of patient-specific functionalization of implants. The observed biological impact due to the delivery of active molecules from the coatings suggests that this strategy may also be employed to deliver antibiotics from similar coatings.

关键词： Implant titanium hydroxyapatite bisphosphonate bone morphogenetic protein-2

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具有战略性的发动机加工方案

现代制造 2013年第28期 38-38页

为汽车工业生产发动机英缸体，需要所使用的刀具在使用寿命上具有可预测性和稳定性。而山特维克可乐满的配刀恰恰具备这些特征并且能够很好地满足制造商对质量、成本效益和可靠性的需求。

关键词：机加工工业生产可预测性使用寿命成本效益发动机稳定性制造商

Mn_(x)Cr_(0.3)Fe_(0.5)Co_(0.2)Ni_(0.5)Al_(0.3)high entropy alloys for magnetocaloric refrigeration near room temperature

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Journal of Materials Science & Technology 2021年第20期79卷 15-20页

作者： Zhihua Dong Shuo Huang Valter Ström Guocai Chai Lajos Károly Varga Olle Eriksson Levente Vitos Applied Materials Physics Department of Materials Science and EngineeringKTH-Royal Institute of TechnologyStockholm SE-10044Sweden College of Materials Science and Engineering Chongqing UniversityChongqing 400030China Department of Physics and Astronomy Division of Materials TheoryUppsala UniversityUppsala SE-75121Sweden Department of Materials Science and Engineering KTH-Royal Institute of TechnologyStockholm SE-10044Sweden Division of Engineering Materials Department of Management and EngineeringLinköping UniversityLinköping SE-58183Sweden ab sandvik Materials Technology R&D Center Sandviken SE-81181Sweden School of Science and Technology Örebro UniversityÖrebro SE-70281Sweden Research Institute for Solid State Physics and Optics Wigner Research Center for PhysicsP.O.Box 49H-1525 BudapestHungary

High entropy alloys(HEAs)based on transition metals display rich magnetic characteristics,however attempts on their application in energy efficient technologies remain ***,we explore the magnetocaloric application for a series of Mn_(x)Cr_(0.3)Fe_(0.5)Co_(0.2)Ni_(0.5)Al_(0.3)(0.8able with Mn concentration.A non-monotonic evolution is observed for both the entropy change and the relative cooling power with changing Mn *** underlying atomic mechanism is found to primarily emerge from the complex impact of Mn on *** magnetocaloric properties can be achieved by tuning Mn concentration in combination with controlling structural phase stability for the designed HEAs.

关键词： High entropy alloys Magnetocaloric materials Magnetic phase transition Experiment and ab initio

Deformation behaviour in advanced heat resistant materials during slow strain rate testing at elevated temperature

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Theoretical & Applied Mechanics Letters 2014年第4期4卷 20-25页

作者： Mattias Calmunger Guocai Chai Sten Johansson Johan Moverare Division of Engineering Materials Department of Management and EngineeringLink?ping UniversitySE-58183 Link?ping Sweden sandvik Materials Technology Strategy researchSE-81181 Sandviken Sweden

In this study, slow strain rate tensile testing at elevated temperature is used to evaluate the influence of temperature and strain rate on deformation behaviour in two different austenitic alloys. One austenitic stainless steel （AISI 316L） and one nickel-base alloy （Alloy 617） have been investigated. Scanning electron microscopy related techniques as electron channelling contrast imaging and electron backscattering diffraction have been used to study the damage and fracture micromechanisms. For both alloys the dominante damage micromech- anisms are slip bands and planar slip interacting with grain bounderies or precipitates causing strain concentrations. The dominante fracture micromechanism when using a slow strain rate at elevated temperature, is microcracks at grain bounderies due to grain boundery embrittlement caused by precipitates. The decrease in strain rate seems to have a small influence on dynamic strain ageing at 650℃.

关键词： dynamic strain ageing slow strain rate tensile testing fracture damage