Investigation of Uncertain Factors on Measuring Residual Stress with Critically Refracted Longitudinal Waves

Round 1

Reviewer 1 Report

This paper present a way of measuring residual stress into samples using critically refracted longitudinal waves. It is well written and I see only a few modification that need to be done before publication.

The first one is on line 115. The Ra of the sample is said to be 2.83mm. I would expect 2.83 micrometers instead of millimeters.

The second is more esthetics. On figure 7 and 8, since there is no progression on the X axis as those are independent samples, I would use a scattered plot instead of putting lines between the points.

Other than this, this paper is good for publication.

Author Response

Dear Reviewer:

      First, the The Ra of the sample is 2.83 micrometers, I have modified it;

      Second, On figure 7 and 8,the results of residual stress for different frequency probes and the X-ray mehtod were compared, therefore, I personally feel that a scattered plot  is better.

                                                     Thank you!

Author Response File: Author Response.pdf

Reviewer 2 Report

Investigation of Uncertain Factors on Measuring Residual Stress with Critically Refracted Longitudinal Wave

By Shunmin Yang, Mingquan Wang and Lu Yang

The paper describes a new method to determine residual stresses due to manufacturing effects. The topic is very important in engineering, because residual stresses influence the fatigue behavior of materials. Generally the novel parts of the research have to be shown clearer. The results have to be shown in comparison to the state of the art ultrasonic solutions.

The improvement to the state of the art ultrasonic measurement is not shown. Therefore, the reader is not able to evaluate if the proposed differences between the frequencies is okay or not. To improve the paper, maybe some theoretical analysis via FEM might be helpful to quantify the effect of the compensation method. Up to now the authors have a lot of curves, but no reference.

For me the results are interesting, but the range of residual stresses is very high. I think this technique is not usable. However, the authors should focus on the problems and how further research could improve the results. I think it is a first step, with average results. A good explanation of error reasons and so on is of great value.

-        All equations have to be improved. They are distorted.

-        The font size changes between equations

-        Most of the plots have to be improved. The axis labels are to small

-        Figure 7 the curve legend is not complete + in Figure (b) the 1 MHz curve is not normalized

-        Consistent varialble names à e.g. t0 is different in the equations

-        The text must be improved. There are many spaces missing and several spelling mistakes

-        The text style changes in the document

Equation (2) –(6) the authors loose a consistent nomenklatur. Sigmas are principle strains and d sigma is a stress. For the reader it is hard to follow.

The statement

“l and m represent the third elastic constants”

is not clear. Please write the third constant and the relation of l and m. For me it is not clear what this elastic constant is. From my experience Aluminum has two, because it is nearly ideally isotropic. Please explain why this constant needed and how it is determined?

For figure 4 the frequencies were not given. The plots show multiple wave packages. I think due to the thin specimen, these are Lamb wave modes and no shear modes. Because for me it is not clear how a shear mode can be excited by the proposed setup.

I propose a major revision of the paper. The main findings have to be presented much clearer, the text, figures and equations have to be improved.

Comments for author File: Comments.pdf

Author Response

Dear Reviewer:

       All contents are explained or modified as required. If there is anything improper, please correct it. Thank you! Please see the attachment for the detailed revision.

1.  Question: About text, figrues and equations.

1)        All equations have been improved;

2)        The font size has been changed between equations.

3)        All of the plots have been redrawed and the axis labels looks clearly;

4)        The cureve of Fig. 7 has been redrawed.

5)        All variable names are corrected.

6)        A lot of spaces missing and several spelling mistakes are corrected.

7)        The text style has been changed.

2. Question: About Lame&Murnaghan constants. (this section has been supplemented in the paper)

3. Question: About Lamb wave. (See attachment for details)

4. Question: About shear wave. (See attachment for details)

       The attachment includes the paper after major revision and the details of author's notes to review.

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

Line 49 longitudinal(LCR) --> space is missing

Variables in the text should be the same fond size as the text.

 

Author Response

Dear Reviewer:

The following is the description of minor revisions. If there is anything improper, please correct it. Thank you!

First, the missing space in Line 49 has been added;

        Second, the font size of all variables has been modified to be the same size as the text.