need someone to edit my essay

Article 1

Background 

   Degrading metal alloys have recently become substantial scientific and clinical interest due to their use as implant materials in bone surgery and cardiovascular surgery and other applications. Degradable iron-based implants were approved for cardiovascular surgery due to low distinctive inflammatory reactions. This article was to verify the usability of iron-based alloys with an open cell structure as a degradable bone replacement material, which provide an osteoconductive surface for the stimulation of osseous integration on and a degradation rate, which lead to overburden the regeneration ability of bone.

Discussion

-the pure iron powder compacts and The powder mixture compacts were sintered at sintering temperatures between 1050 and 1120 °C. the Sintering densities were obtained by adding small amounts of boron which give the formation of fine distributed small pores, the Phosphorus contents provide maximum density, but higher contents of phosphorus form the brittle intermetallic phases. while The addition of boron leads to lower densities, phosphorus help on increasing mechanical strength. Therefore, a powder mixture of Fe3P and carbonyl iron was prepared on these experiments to prepared Fe0.6P alloy. The sintered density of the various alloys is shown in 

-cell toxicity tests were carried out To characterize the iron-based alloys in vitro using a perfusion chamber system to simulate the dynamic body environment. Fibroblasts were maintained successfully for the duration of the experiment.

 

-the comparison between alloys shows, that cell counts on the iron and alloyed iron discs show cell proliferation with the highest proliferation calculated as 1.6 wt.-% phosphorus-containing alloys.

 

-The study shows that use phosphorus can be strengthened by open-cell metal without the risk degradation decreasing rates as result shows that there is no inflammatory response on the bone or the surrounding tissue, which gives rise to the good biocompatibility of iron to be used in biomaterial applications.the picture below show electron microscopy of a metal foam produce by a Fe0.6P alloy.

 

Challenge and Future Outlook

     the implant studies display a large fraction of residual implant material, even after 12 months implantation time, which means that tests only give indications for the degradation time in vivo test. Thus show that further work has to be done to support increase the degradation rates on the iron alloys. 

Article2

Background 

   Developing metals alloy is an important topic related to biomaterials studies. Scientists should consider highly corrosion resistant in addition to biocompatible, the bioresorbable metal alloys give superior functionality in some biomedical applications. Scientists make much more research on magnesium alloys and other metals but iron-based alloys were less studied. However, in most cases, it is reported that the passivation of the steel substrate leads to a too low dissolution rate. To increase the corrosion rate the passivation can be deteriorated by the inclusion of alloying elements, which form local cathodes and thereby promote the anodic dissolution of the iron-rich phase.

Discussion

-In this study, for the first time, iron-manganese-silver alloys synthesized by additive manufacturing techniques. We can define additive manufacturing as the process where a digital 3D design data is depositing material by building up a component in layers. Additive Manufacturing also called 3D printing in some cases. Additive Manufacturing methods are used increasingly in Series biomedical Production.

-Based on current studies, it illustrates that silver particles effectively distributed in the matrix which can be obtained, providing cathodic sites in the composite material.

 

-As a result of this study, a new method for processing of immiscible materials is done. On basis of the Selective Laser Melting technique and the presented TWIP-silver alloy starting by the mechanical properties are which barely deteriorated compared to pure TWIP steel, Ag-particles fairly homogenous distribution in the TWIP-matrix is successfully achieved and finally the dissolution rate has increased by the addition of silver.

 

Challenges And Future Outlook

In the future, further research is needed to make scientists fully understand the connection between silver content, alloy performance, and processing concerning the corrosive and mechanical behavior. For example, corrosion analysis has to be deeply understood to clarify detailed chemical reactions proceeding between the surrounding iron matrix and silver particles.

the range of silver addition should be broadened much more to fully evaluate the possible dissolution rates. The adaption of the material properties needs Further developments to the stiffness of bone tissue, acquire by part design based on non-stochastic cellular structures. also, Long-term experiments are necessary for evaluation of the mechanical properties in the course of the degradation of the implant performance as well as the degradation behavior in body ambiance in general.

References

[5] T. Niendorf, F. Brenne, P. Hoyer, D. Schwarze, M. Schaper, R. Grothe, M. Wiesener, G. Grundmeier, and H. J. Maier, “Processing of New Materials by Additive Manufacturing: Iron-Based Alloys Containing Silver for Biomedical Applications,” Metallurgical and Materials Transactions A, vol. 46, no. 7, pp. 2829–2833, May 2015.

[6] P. Quadbeck, R. Hauser, K. Kümmel, G. Standke, G. Stephan, B. Nies, S. Rößler, and B. Wegener, “Iron Based Cellular Metals For Degradable Synthetic Bone Replacement ,” Iron Based Cellular Metals For Degradable Synthetic Bone Replacement , (IFAM-DD), Fraunhofer Institute Ceramic Technologies and Systems, InnoTERE GmbH, Ludwig-Maximilians Universität München.

of adjacent bone tissue, achievable by part design based on

non-stochastic cellular structures.

[11,29]

Long-term ex-

periments are necessary for evaluation of the mechanical

performance in course of the degradation of the implant as

well as the degradation behavior in body ambience in

general. Finally, other formerly non-producible material

combinations will be contemplated for proc.