In-Situ Corrosion Testing of Carbon Steel and EHLA Clad Materials in High-Temperature Geothermal Well

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The manuscript presents a valuable in-situ corrosion assessment of EHLA-cladded stainless steel and nickel-based alloys under high-temperature geothermal well conditions. The work is technically strong, and the field-based exposure adds meaningful practical relevance. Below are specific comments,

1. Line 21, the abstract is informative, however, incorporating a quantitative detail may enhance its overall impact and strength.
2. In section 2.1, consider adding a simple schematic of the sample holder to enhance clarity.
3. Line 146, consider adding representative strain values comparing the 30% and 100% YS conditions to strengthen this section.
4. Line 159, clarifying the exact physical limitation that prevented achieving certain stress levels would assist the reader.
5. Line 176, provides explanation for selecting a 1 mm scratch width for galvanic testing.
6. Line 209, rephrasing ‘lowered down in a slow manner’ with more precise technical wording could improve clarity.
7. Line 394, please comment on whether Nb-depleted regions or Laves phases were detected, as these features can influence Alloy 625 corrosion performance.
8. Line 446, considering adding the explaining the distinguishing morphological features of the solidification cracks.
9. Several statements repeat similar conclusions (such as ‘negligible corrosion’).
10. Proofread the entire manuscript for grammar, punctuation, and consistency in material notation.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

This work presents an experimental study on the corrosion performance of carbon steel and EHLA clad materials in a high-temperature geothermal environment. Overall, this work is interesting, but it needs to be improved according to my following suggestions.

1. Figure 4: Units should be included.
2. Lack of quantitative analysis of corrosion behaviors. If possible, quantitative electrochemical tests are recommended. Like a potentiodynamic polarization test or EIS test.
3. The 14-day test is too brief to fully assess long-term corrosion behavior in geothermal wells, where casings may operate for decades.
4. Cracks are attributed to production (solidification), but no quantitative data on crack density, length, or frequency across samples is given.
5. The influence of EHLA process parameters (such as laser power and cooling rate) should be considered.
6. Although scratches were designed to simulate a high cathode/anode area ratio, the galvanic effect observed in practice was not significant, possibly related to electrolyte conductivity, temperature, or the actual potential difference.
7. Analyze the economic viability and feasibility of EHLA technology compared to traditional cladding.
8. Tested in one well with near-neutral pH and low salinity; not representative of harsher geothermal fields.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

The authors have addressed the comments, and the manuscript can be accepted for publication.

Reviewer 2 Report

Comments and Suggestions for Authors

accept