Porous and dense TiNi alloys were successfully fabricated by powder metallurgy(P/M) method, and to further improve their surface biocompatibility, surface modification techniques including grind using silicon-carbide(...Porous and dense TiNi alloys were successfully fabricated by powder metallurgy(P/M) method, and to further improve their surface biocompatibility, surface modification techniques including grind using silicon-carbide(SiC) paper, acid etching and alkali treatment were employed to produce either irregularly rough surface or micro-porous surface roughness. X-ray diffractometry(XRD), scanning electron microscopy(SEM) and energy dispersive X-ray spectroscopy(EDX) attached to SEM were used to characterize surface structure and the Ca-P coatings. Effects of the above surface treatments on the surface morphology, apatite forming ability were systematically investigated. Results indicate that all the above surface treatments increase the apatite forming ability of TiNi alloys in varying degrees when soaked in simulated body fluid(SBF). More apatite coatings formed on TiNi samples sintered at 1050℃ and 1100℃ due to their high porosity and pure TiNi phase that is beneficial to heterogeneous nucleation. Furthermore, more uniform apatite was fabricated on the sample sintered from the mixture of Ni and Ti powders.展开更多
The issue of the building materials biocorrosion has a significant economic dimension because it results in the costly repair. The start and the course of corrosion are conditioned by many factors which undoubtedly in...The issue of the building materials biocorrosion has a significant economic dimension because it results in the costly repair. The start and the course of corrosion are conditioned by many factors which undoubtedly include biological effects like the influence of vegetation and microorganisms causing the so called microbial corrosion. Microorganisms have also a considerable share in the decay and degradation of different building materials. The activity of sulphuratum is the keystone of many processes in nature and in industry. The sulphuric bacteria oxidize hydrogen sulphide produced by sulphate-reducing bacteria into sulphuric acid resulting in the acid or sulphate corrosion of cement stone. The paper is aimed on evaluation of porosity and roughness of concrete samples surface as elementary characteristics of microbial corrosion. After 4 months exposure to the real conditions in sewers deposition the changes were observed by confocal laser microscopy and consequently analyzed and interpreted.展开更多
基金Project(51274247) supported by the National Natural Science Foundation of ChinaProject(2014zzts177) support by the Fundamental Research Funds for the Central Universities,China
文摘Porous and dense TiNi alloys were successfully fabricated by powder metallurgy(P/M) method, and to further improve their surface biocompatibility, surface modification techniques including grind using silicon-carbide(SiC) paper, acid etching and alkali treatment were employed to produce either irregularly rough surface or micro-porous surface roughness. X-ray diffractometry(XRD), scanning electron microscopy(SEM) and energy dispersive X-ray spectroscopy(EDX) attached to SEM were used to characterize surface structure and the Ca-P coatings. Effects of the above surface treatments on the surface morphology, apatite forming ability were systematically investigated. Results indicate that all the above surface treatments increase the apatite forming ability of TiNi alloys in varying degrees when soaked in simulated body fluid(SBF). More apatite coatings formed on TiNi samples sintered at 1050℃ and 1100℃ due to their high porosity and pure TiNi phase that is beneficial to heterogeneous nucleation. Furthermore, more uniform apatite was fabricated on the sample sintered from the mixture of Ni and Ti powders.
文摘The issue of the building materials biocorrosion has a significant economic dimension because it results in the costly repair. The start and the course of corrosion are conditioned by many factors which undoubtedly include biological effects like the influence of vegetation and microorganisms causing the so called microbial corrosion. Microorganisms have also a considerable share in the decay and degradation of different building materials. The activity of sulphuratum is the keystone of many processes in nature and in industry. The sulphuric bacteria oxidize hydrogen sulphide produced by sulphate-reducing bacteria into sulphuric acid resulting in the acid or sulphate corrosion of cement stone. The paper is aimed on evaluation of porosity and roughness of concrete samples surface as elementary characteristics of microbial corrosion. After 4 months exposure to the real conditions in sewers deposition the changes were observed by confocal laser microscopy and consequently analyzed and interpreted.
