Ultrasonic Inspection for Welds with Irregular Curvature Geometry Using Flexible Phased Array Probes and Semi-Auto Scanners: A Feasibility Study
Round 1
Reviewer 1 Report
Thanks for sharing your work. Please find my comments in the attached pdf.
Comments for author File: 
Comments.pdf
Author Response
Please see the attachment.
Author Response File: 
Author Response.docx
Reviewer 2 Report
The authors developed a flexible array probe and semi-auto scanner for non-destructive inspection of complex curvature-shaped specimens that are coupled by welding. They demonstrated better reliability of flaw detectability from the developed scanners as compared to the typical PA scanners. The manuscript is thorough and scientifically sound. However, the authors should address the following issues to improve the impact and readability of the manuscript.
In any scanning modality, the choice of the transducers and pitch etc. are decided by the dimensions of the entity that is aimed to be scanned. The authors should include the thought process for the geometry they used.
Lowest US wavelength is double the pitch -- this bounds the maximum US frequency and hence the transducers bandwidth. The authors should include this discussion. Also, the maximum frequencies should be tabulated in table 1.
The first and third columns of table 2 has no values in the first six rows. While it can be be concluded that these are the material properties and will be same as the second column, authors should think of a better way of representing this.
Some of the dimensions are missing in Fig. 6.
In Fig. 11(b) and (d), the center frequency analysis resulted 5.4 and 4.8 MHz center frequency. Authors should elaborate how these numbers were obtained and support the method with a reference.
Moreover, the peak frequency for the T/R and P/E (fig 11 b and d res.) are very distinct: 5 and 7 MHz. While the geometry and the US elements are similar, what factors are responsible for this difference should be discussed.
Line 107: First, in FPAPr, the element was placed...... - Here it is not clear what 'the element' stands for.
Table 3: Aperture unit is missing.
Several statements need supporting references, such as:
line 115: Lastly, the PA probe design considered the generation of side lobes.
Line 112:grass echo is lowered due to broadband characteristics.
Line 141: single bounce technique
Line 143: CIVA
A thorough proofread is also needed to correct for the typos such as:
--------Line 182: 'Was' -- w needs to be in lower case.
Line 281: space missing before 'Generally'.
Author Response
Please see the attachment.
Author Response File: Author Response.docx
Round 2
Reviewer 1 Report
Thanks for responding to my comments and making amendments to the manuscript.
