Round 1

Reviewer 1 Report

The article really “Casting Blanks Cleanliness Evaluation Based on Ultrasonic Microscopy and Morphological Filtering” was improved taking into account most of remarks. The article possess now well-defined and interesting material related to application of acoustic microscopy and image processing for assessing properties of the cast material. There are only some errors or comments requiring minor revision:

1. In the abstract (line 21) the anisotropy of the material is related to scattering of ultrasonic waves. Probably more correctly will state that the anisotropy of material grain will lead to the scattering of the waves, not general anisotropy of material.
2. In the introduction (91) it is not clear statement “the signal delay time is too long”. Why this is disadvantage of ultrasonic guided wave signals is not clear. It seems as some misunderstanding.
3. In page 3, line 100 “… ultrasonic microscope” should not start from the capital letter.
4. Page 4 line 136 and in other places. The term “inner arc” is very specific for casting technology and will be not clear for many readers if not explained. In the analysis of the results there is no any statement relating the parameters of observed inclusions to casting technology. So, it would be more clear to name them as top or bottom surface or side A and side B as latter defined in article.
5. Page 5 lines 170-181. The term “detectable thickness” is also discussible, more correctly to name “inspection depth”, “inspection zone”. The same are related to “detection ranges”, “longitudinal wave detection”, “ultrasonic detection area”, “detection diagram”. In all these cases better to change the term “detection” to term “inspection”. The term “detection” is more related to detection of the defect inclusion, but not to the particular process of detecting defects.
6. Page 7 the line 224 should not start with the capital letter.
7. Page 7 line 245 should be “… casting blanks… ” not “ …casing blanks…”. Also the same remark 1 anisotropy of grains not the anisotropy of blanks leads to scattering.
8. The title of Figure 9 should start from capital letter.

Author Response

Thanks to the reviewer’s detailed comments, the article has been revised.To better show the revisions we made,please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

See attachment.

 

Comments for author File: Comments.pdf

Author Response

Thanks to the reviewer’s detailed comments, the article has been revised.To better show the revisions we made,please see the attachment.

Author Response File: Author Response.pdf

This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.

Round 1

Reviewer 1 Report

In general, the topic “Casting Blanks Cleanliness Evaluation Based on Ultrasonic Microscopy and Morphological Filtering” is related to application of advanced ultrasonic technologies for assessment of material properties and is quite interesting, as well the final results of the research. However, the research material laid out in the article possess multiple deficiencies. The most important is:

Presence of vary basics of ultrasonic inspection and image processing at the same time missing very important details. The examples of basics: first paragraph of 2.2 section; structure of acoustic microscope (authors do not develop microscope), it means the Figure 2 is necessary; section 3.1 in general; paragraph from line 177. The missing information: information about sharpness of the focused transducers (it determines the thickness of the layer which is investigated); relation of the dimensions of the inclusions with wavelength (it in general determines possibility of detection and assessment); absence of original ultrasonic images, only processed binary images are shown (in general they do not give any understandable information); The authors states that the research was carried in two aspects one of them is hardware (line 102), however the authors do not develop any hardware. Authors also states that they are targeting to obtain fast inspection, however there are no any information about duration of inspection. This is very important it is related to the scanning steps. In the case of larger steps, some of the inclusion can be missing in the data, small steps lead to increased scanning time. This information also is missing in the article. According my understanding there are many not correct technical English expressions or statements and article needs essential English language revision. The examples are: “…it is easy to produce complex ultrasonic 20 scattering signal,…”(line 20); “…three-25 dimensional space of materials … ” (line 24) and etc. the authors uses the term “sound pressure” (lines 180-181)– in the solids there are elastic waves not pressure waves; “Spacemen detection schematics” (figure 8); and etc. The term “dynamic focusing “ also usually have another meaning related to ultrasonic phased array. Probably it should not be used there or at least explained what is meant by it in more details.

The other remarks are:

Many descriptions in the figures are almost unreadable (too small fonts). In Figures 1, 8 and 10 parts a), b) are denoted several times (duplicated); There are several technical errors of the text and it should be reviewed very carefully.

Reviewer 2 Report

Brief summary:

The authors present an interesting study where ultrasound at 100 MHz is used to evaluate large inclusions (>20 µm) in a blank steel sample from continuously cast billets. Furthermore, to distinguish the measurement signal from the noise a morphological filtering is proposed.

Broad comments:

The scope of the manuscript is quite interesting and new techniques are important for the quality assurance of produced steels.

The method is described as being faster than conventional analysis method, please make a quantitative comparison. How long time does a scan take from taking the sample to having the results?

Moreover, the comparison with *conventional* methods should be more quantitative. What are the uncertainties in the respective measurements? How many inclusions are found with each respective method?

Specific comments:

L103: Please, define high-frequency ultrasound. What properties are dependent on the frequency and what was the underlying reason to select 100 MHz?

L115: “… detection in the micrometer level” please, expand this in terms of current theoretical vs. practical limits.

L133: What is the size of billets studied?

L135: Figure 1 a) shows a blooms caster where it is stated L212 that it is billets that are analyzed.

L201: What is actually filtered away by this method?

L205-L211: This is a very unclear paragraph, please clarify.

L269: “… the superiority of the new method are verified”: please support this with quantitative results.

L299: Please, explain the choice of regression line in relation to the inclusion size cut-off at 40 µm.

L340: “ultrasonic technology has a good ability to detect inclusions of all sizes”, this state is by no means supported by the data given in Figure 10.

 

Please discuss the following in detail:

Limits on sample size (thickness) Distinction between pores and inclusions.