The Effect of Cu Additions on the Antibacterial Properties of Metallic Glassy Ni₅₀TM₅₀ (TM; Ti, Zr) Binary Systems

Round 1

Reviewer 1 Report

This manuscript reports experimental preparation, structural characterization and antibacterial behavior of NiTM (TM; Ti, Zr) alloys claimed as metallic glass. However, these are amorphous alloys and cannot be named as metallic glasses, because the amorphous stucture was obtained by ball milling.

The authors compare antibacterial properities of cold sprayed onto SUS 304 substrat amorphous layers (Ti50Ni50, Zr50Ni50, Cu50Ti40Ni10, Cu50Zr40Ni10) with corresponing biofilm formation on pure powder elemental alloys (Cu, Zr, Ni, Ti ). All the results and discussion might be of some engineering interest to the materials engineering community. However, the text and title should be completely rebuilt.
English should be also improved by native speaker, as there are some strange expressions, like "as- arc melt"

 

Author Response

Dear sir,

please find the attached word doc, reply to your kind comments

Dr. Ahmad Aldhameer

Author Response File: Author Response.docx

Reviewer 2 Report

（1）The work doesn’t show the bonding surface between the sprayed sample(s) and the substrate, thus it is hardly known whether the two can be effectively bonded.

（2）The shape of the metal powder, which is produced by crushing, is saliently different. In this case, during the cold spraying, will there be a large number of defects inside the coating, which may badly results in the mechanical properties of the coating？

（3）Try to strengthen the research result with more detective studies instead of mere antibacterial studies.

Author Response

Dear sir,

please find the attached word doc, reply to your kind comments.

Dr. Ahmad aldhameer

Author Response File: Author Response.docx

Reviewer 3 Report

 

Report on manuscript processes-1790127

Title: “Influence of Cu additives on the antibacterial behavior of metallic glassy Ni50TM50 (TM; Ti, Zr) binary systems”

By Ahmad Aldhameer et al.

 

In the manuscript, the authors report on preparation by arc melting technique of alloys Ni50Ti50, Ni50Zr50, Cu50Ti40Ni10, and Cu50Zr40Ni10 and, then, they were used for production of metallic glassy powders by high-energy ball milling over 50 h. The as-milled powders, in fact metallic glasses, were coated with SUS304 sheets by cold spray method. The authors detected that Cu addition to the two binary Ni50TM50 (TM; Ti, Zr) alloys revealed better antibacterial characteristics. The results presented here may be of interest for potential readers of the journal “Processes”. However, some revision should be made as reported just below:

 

1)      Page 1: “Metallic glasses (MGs) are a type of metastable alloys that came into existence during the past sixty years as a result of the use of novel preparation procedures employed for obtaining significant deviations from equilibrium [2]” The authors use in many cases the term “equilibrium”. In this and other sentences this term should be clarified.

2)      Page 2: the sentence “Thus, MGs have become promising candidates for hi-tech applications in almost all industrial, medical, sports, and life science area.” almost duplicates the following one “As a consequence, MGs have emerged as potentially advantageous candidates for high-tech applications across almost the whole spectrum of industrial, medical, athletic, and life science fields [5]” Therefore, the first sentence should be omitted.

3)      Page 3: “Despite their excellent resistance to corrosion, stainless steel alloys do not demonstrate significant antibacterial characteristics [15,16]. This is in contrast to the fact that they have a great resistance to corrosion.” The second sentence duplicates somewhat the first sentence and should be omitted.

4)      Page 3: The information “the present study is a component of a project (EA074C) that was funded by the Kuwait Foundation for the Advancement of Sciences (KFAS), under Contract number: PR1915EC01. The present study is being done to investigate the antibacterial qualities of a composite made of coated metallic glassy particles/ SUS304 to be compared with the results obtained upon coating with pure metals Ti, Zr, Cu and Ni, as well as binary Ni50Ti50, and Zr50Ni50 systems. During the second stage of this research project, the electrochemical corrosion properties and mechanical behavior of these systems will each be investigated in more depth.” concerns acknowledgements and it is not necessary in the Introduction section.

5)      In general, the introduction section looks to be unproportionally long. The authors should present the most important information regarding the problems they deal with in the present manuscript omitting the unimportant information. This also concerns the abstracts.  

6)      Page 4: “The as-prepared binary and ternary master alloy buttons were simply crushed separately into small pieces with a 20 -ton cold press. The as- snipped bulk pieces were disintegrated into large particles of ~ 150 mm in diameter(Figure 2a), using Vibratory Disc Mill RS 200, provided by Retsch GmbH, Retsch-Allee 1-5, 42781 Haan, Germany” In this and other places there is no need to report every time the full post addresses of companies producing the equipment being used. Only the names of companies are necessary in such cases.

7)      Page 8: The authors report “In this study, biofilm formation on pure powder elemental alloys (Cu, Zr, Ni, Ti ), binary (Ti50Ni50, Zr50Ni50), and ternary (Cu50Ti40Ni10, Cu50Zr40Ni10) systems individually  cold sprayed onto SUS substrate,” Does this biofilm formation was uniform in the above-mentioned cases?

8)      The authors use, as components of the materials being under study, titanium and zirconium, very recognized getters. The sample surfaces are obviously was partly oxidized during the present experiments. Is it important in the present experiments? How this effect was eliminated?

9)      Page 9: The authors report “In order to obtain amorphous phases of NiTi, and NiZr systems, the as- arc melt disintegrated powders were subjected to severe lattice imperfections upon high energy ball milling for 50 h.” The time of the high energy ball milling is too long. Did the authors detect some additions of the balls’ materials in the samples under study after finishing the milling process?

10)  The conclusion section should be more informative.

11)  Finally, I would suggest the author to ask somebody profound in English to correct carefully the whole text.

Author Response

Dear sir,

please find the attached word doc, point by point response to your kind comment.

Dr. Ahmad aldhameer

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

R1. We thank the Respected Reviewer for his kind comments. In this regard we would like to explain that metallic glassy alloys are named GLASSES when they reveal Transition temperature (Tg) regardless to the approach used for the sample preparations.

Authors response is not acceptable to me. Metallic glasses defined as amorphous alloys that exhibit a glass transition. However, the most important feature of BMGs that, along with other glasses, distinguish them from general amorphous materials is the glass transition that transforms supercooled liquids into a glassy state when cooled from high to low temperature.

R3. Arc melt/arc melting is not an expression, it is a well know process for fabrication of metal alloys. For materials scientists and metallurgists this is a very fundamental equipment. Thank you

I know this technique very well. I meant that you should use "as-cast" or "as-melted" rather that "as- arc melt", which sounds strange to me

 

My final conclusion is that the manuscript is still not acceptable for publication, as these materials are "amorphous alloys", not "metallic glasses"

 

 

 

Author Response

Dear sir,

please find attachment word doc, point by point response to your kind comments

best regards

 

Dr. Ahmad Aldhameer

Author Response File: Author Response.docx