Structure and Properties of DLC Films Deposited on Mg Alloy at Different C2H2 Flows of Magnetron Sputtering Process

Coatings

Haitao Li¹  Donghai Cheng¹  Pengfei Sun² 

[1] College of Aeronautical Manufacturing Engineering, Nanchang Hangkong University, Nanchang 330063, China;College of Material Science and Engineering, Jiamusi University, Jiamusi 154007, China;

关键词: DLC film;    wear resistance;    corrosion;    magnetron sputtering;    Mg alloy;   

DOI  :  10.3390/coatings11070815

来源: DOAJ

【 摘 要 】

Diamond-like carbon (DLC) film is widely used due to its excellent properties, such as high hardness and high wear resistance. To investigate the advantages of DLC film applied on the surface of Mg alloy, direct current (DC) pulse magnetron sputtering was used to prepare DLC film via plasma sputtering a graphite target and introducing C₂H₂ gas. The silicon interlayer was fabricated by sputtering the Si target. A scanning electron microscope (SEM), transmission electron microscope (TEM), a nano-indentation instrument, an electrochemical workstation and a pin-on-disc tester were employed to obtain the surface morphology, microstructure, mechanical properties, corrosion behavior and wear resistance of the obtained film, respectively. The results show that the DLC films are dense and compact, and the structure changes from amorphous to nanocrystalline with the increase of C₂H₂ flow. The film prepared at low C₂H₂ flow has larger surface roughness, lower deposition rate, higher hardness and elasticity modulus, poorer corrosion resistance and better wear resistance, compared with the film prepared at higher acetylene flow. The self-corrosion potential of the obtained DLC film is higher than −0.95 V, the corrosion current density is 10⁻⁷ A/cm² orders of magnitude, and the wear rate is 10⁻⁹ mm³/Nm orders of magnitude. The friction coefficient of the film is less than 0.065, the hardness is 17.3 to 22.1 MPa, and the elastic modulus is 145 to 170 MPa. The DLC films obtained on the surface of AZ91 alloy have good comprehensive properties.

【 授权许可】

Unknown