Abstract
The strain properties of the W-DLC coatings were evaluated. W-DLC coatings with various concentrations were prepared by chemical vapor deposition and DC magnetron co-sputtering of a tungsten metal target. Strain was applied to a sample in a four-point bending configuration. The electrical resistance was proportional to the amount of compression and tensile strain, and the gauge factor varied according to the metal concentration. Transmission electron microscope was employed for structure analyses. It was clarified that the structure of the W-DLC was granular. The variation of the resistance under the strain could be explained by a simplified model related to the distance between the clusters. The W-DLC coatings have the potential for strain sensor application.