Authors: Ranjan Kumar Ghadai | G. Shanmugasundar | Lenka Čepová | Santanu Das | Premchand Kumar Mahto | Kanak Kalita
Source: Frontiers in Mechanical Engineering (article, 2023-12-01)
Field: Materials Science — Materials Chemistry

A temperature-based synthesis and characterization study of aluminum-incorporated diamond-like carbon thin films The present work deals with the study of various properties of aluminum (Al)-incorporated diamond-like carbon (DLC) thin films synthesized using the atmospheric pressure chemical vapor deposition (APCVD) technique by varying the deposition temperature ( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="m1"><mml:mrow><mml:msub><mml:mi>T</mml:mi><mml:mi>d</mml:mi></mml:msub></mml:mrow></mml:math> ) and keeping the <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="m2"><mml:mrow><mml:msub><mml:mi>N</mml:mi><mml:mn>2</mml:mn></mml:msub></mml:mrow></mml:math> flow rate constant. Surface morphology analysis, resistance to corrosion, nanohardness ( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="m3"><mml:mrow><mml:mi>H</mml:mi></mml:mrow></mml:math> ), and Young’s modulus ( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="m4"><mml:mrow><mml:mi>E</mml:mi></mml:mrow></mml:math> ) of the coatings were carried out using atomic force microscopy (AFM), corrosion test, scanning electron microscopy (SEM), and nanoindentation test, respectively. SEM results showed a smoother surface morphology of the coatings grown at different process temperatures. With an increase in process temperature, the coating roughness (Ra) lies in the range of 20–36 µm. The corrosion resistance of the coating was found to be reduced with a consecutive increase in the deposition temperature from 800 <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="m5"><mml:mrow><mml:mo>℃</mml:mo></mml:mrow></mml:math> to 880 <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="m6"><mml:mrow><mml:mo>℃</mml:mo></mml:mrow></mml:math> . However, above 880 <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="m7"><mml:mrow><mml:mo>℃</mml:mo></mml:mrow></mml:math> , the resistance increases further, and it may be due to the presence of more Al weight percentage in the coating. The nanoindentation result revealed that <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="m8"><mml:mrow><mml:mi>H</mml:mi></mml:mrow></mml:math> and <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="m9"><mml:mrow><mml:mi>E</mml:mi></mml:mrow></mml:math> of the coating increase with an increase in the CVD process temperature. The elastic–plastic property indicated by <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="m10"><mml:mrow><mml:mi>H</mml:mi><mml:mo>/</mml:mo><mml:mi>E</mml:mi></mml:mrow></mml:math> and <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="m11"><mml:mrow><mml:msup><mml:mi>H</mml:mi><mml:mn>3</mml:mn></mml:msup><mml:mo>/</mml:mo><mml:msup><mml:mi>E</mml:mi><mml:mn>2</mml:mn></mml:msup></mml:mrow></mml:math> , which are also indicators of the wear properties of the coating, were studied using the nanoindentation technique. The residual stresses ( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="m12"><mml:mrow><mml:mi>σ</mml:mi></mml:mrow></mml:math> ) calculated using Stoney’s equation revealed a reduction in residual stress with an increase in the process temperature. Materials science ; Analytical Chemistry (journal) ; Chemistry ; Chromatography Diamond and Carbon-based Materials Research ; Metal and Thin Film Mechanics ; Carbon Nanotubes in Composites