Porous Fiber Metal Research Articles

РАЗРАБОТКА И ИССЛЕДОВАНИЕ СВОЙСТВ ПОРИСТОВОЛОКНИСТЫХ МЕТАЛЛИЧЕСКИХ МАТЕРИАЛОВ ДЛЯ ЗВУКОПОГЛОЩАЮЩИХ КОНСТРУКЦИЙ И УПЛОТНЕНИЙ ГАЗОТУРБИННЫХ ДВИГАТЕЛЕЙ

РАЗРАБОТКА И ИССЛЕДОВАНИЕ СВОЙСТВ ПОРИСТОВОЛОКНИСТЫХ МЕТАЛЛИЧЕСКИХ МАТЕРИАЛОВ ДЛЯ ЗВУКОПОГЛОЩАЮЩИХ КОНСТРУКЦИЙ И УПЛОТНЕНИЙ ГАЗОТУРБИННЫХ ДВИГАТЕЛЕЙ

Fluid-Solid Static Coupling for Saturated Porous Fiber Metals in the Biot's Acoustic Theory

Fluid-Solid Static Coupling for Saturated Porous Fiber Metals in the Biot's Acoustic Theory

Research Advancement of Porous Fiber Metals

Porous fiber metals are a kind of metallic materials which have a through-pore structure by forming and sintering.They have the advantages of light weight,high surface area and high specific strength.They are widely used in engineering field.This paper described the progress and application of porous fiber metals.And analysed the progresses of titanium fiber porous materials,nickel fiber porous materials,FeCrAl fibrous porous materials,copper fiber porous materials and stainless steel fiber porous materials,and prospected their further development.

Progress of Application Researches of Porous Fiber Metals.

Metal fiber porous materials with intrinsic properties of metal and functional properties of porous materials have received a great deal of attention in the fundamental research and industry applications. With developments of the preparation technologies and industrial requirements, porous fiber metals with excellent properties are developed and applied in many industry areas, e.g., sound absorption, heat transfer, energy absorption and lightweight structures. The applied research progress of the metal fiber porous materials in such application areas based on the recent work in our group was reviewed in this paper.

Calculation of sound absorption characteristics of porous sintered fiber metal

Focusing its attention on porous sintered fiber metal, this paper presents a simple extended acoustical model on the basis of Biot–Allard model by using the idea of convective heat transfer in metallic tube for reference in order to calculate the sound absorption characteristics of porous sintered fiber metal. The sound absorption coefficients and the specific surface acoustic impedances of one-layer porous fiber metal sheets, two-layer-assembled and three-layer-assembled porous fiber metal sheets are calculated by using the extended and Biot–Allard model and then compared with the corresponding measured values. By comparing, it is shown that the theoretical results calculated by using the extended model fit the measured ones better. Finally, those above-mentioned results are further discussed and analyzed.

A Long-Term Study on Defect Filling and Bone Ingrowth Using a Canine Fiber Metal Total Hip Model

When performing primary and revision total hip arthroplasty (THA), bone defects are often encountered. At present, grafting osseous defects with autogeneic bone is a common means of treatment. In this study, defects in bone were created in the femora and acetabula of dogs being treated with cementless THA with a fiber metal implant (Group A) or a hydroxyapatite tricalcium phosphate (HA/TCP) sprayed implant (Group B). The following methods of defect filling were compared: (1) leaving defects unfilled, (2) filling with autogeneic bone graft, (3) filling with a 50:50 mixture of autograft and a biphasic ceramic composed of HA/TCP, and (4) filling with a collagen-HA/TCP-bone marrow mixture. Analysis of defect healing and the extent of ingrowth into the overlying fiber metal, at defect sites and sites distant from defects, was made at six, 12, and 24 weeks postimplantation. Defect healing was enhanced at six and 12 weeks in all grafted groups when compared with ungrafted controls. Bone ingrowth into the porous fiber metal overlying the defects was not significantly affected by grafting the defects, compared with the ungrafted defects. The extent of bone ingrowth into the fiber metal acetabular implant at sites away from the defects increased during the entire study. In contrast, the extent of bone ingrowth on the femoral side was maximal at 12 weeks. The HA/TCP coating enhanced ingrowth into the acetabular component at 12 weeks, compared with the uncoated prosthesis, but did not enhance ingrowth on the femoral side. The data from this study demonstrate that defect healing is enhanced with graft materials. However, this does not necessarily result in increased ingrowth into porous surfaces overlying osseous defects. General bone ingrowth and ingrowth at defect sites at 12 weeks postimplantation can be enhanced on the acetabular side with the use of HA/TCP-sprayed implants. However, no positive effect is seen with the use of an HA/TCP-sprayed femoral implant.

Invasion of bone into porous fiber metal implants in cats.

Bone ingrowth in porous Ti-6Al-4V implants in feline femurs was assessed for the amount and composition 4, 12 and 26 weeks after implantation. During the first 12 weeks there was a rapid ingrowth that levelled out during the ensuing weeks. Bone had penetrated the implants to an average depth of 0.5 mm over their entire surface at 26 weeks. The ingrown bone was deficiently mineralized at 4 and 12 weeks, but reached full mineralization at 26 weeks. A low calcium to phosphorus ratio persisted at all observation times. The ingrown tissue was compared to bone filling drill holes that had been made in the trochanters contralaterally to the implants. By means of radioactive strontium, the mineral deposits in the holes and implants could be compared. The overall results indicate that bone ingrowth in a porous implant and bone healing are similar processes both qualitatively and quantitatively.

Total surface hip arthroplasty in dogs using a fiber metal composite as a fixation method

A total hip surface replacement was performed on 13 adult mongrel dogs using a porous fiber metal composite for fixation to bone. Titanium fiber composite rings were molded onto cylindrical acetabular prostheses, and cobalt-chrome fiber inserts were sintered onto the cast cobalt-chrome femoral components. The animals were allowed unrestricted walking. Four dogs were sacrificed between 3 and 5 weeks, five at 7 weeks, one with a femoral neck fracture at 12 weeks, and three at 26 weeks. Bone ingrowth was accomplished in 20 of the 26 prosthetic components. This included 12 femoral components and eight acetabular. The main reason for failure appeared to be inadequate primary fixation, secondary to either poor design or technical difficulties experienced during the surgical procedure.

Anodic polarization of porous fiber metals.

Anodic polarization of porous fiber metals.