Resumen
Battery waste is one of waste that can damage the environment and there has not been much good processing in Indonesia. Even though, battery waste contains carbon which can be used as a target material for deposition of carbon films using plasma sputtering. The focus of this research is to determine the effect and optimum power value of plasma argon generation, so that the power generation value can produce the highest hardness value of SKD11 steel can be obtained. The method used as plasma is argon gas. Argon plasma is generated by using a 40 kHz LGF. Thin film of carbon synthesize on SKD11 steel was tested to determine the value of hardness using micro hardness Vickers. Based on the experimental result, the optimum power treatment obtained at 340 Watt with the highest average hardness value is 316.7 HV. Based on SEM-EDX observation, it can be described that comparison of atomic carbon from carbon rods without treatment (1.5 %) and carbon thin films on SKD11 with optimum power treatment (13.36 %) show different value. Number of atomic carbon of thin films on SKD11 with power treatment more higher than atomic carbon of carbon rods without treatment, it causes higher hardness value of thin films on SKD11 steel after plasma sputtering treatment on optimum power parameters than SKD11 steel without treatment. SKD11 steel that has a high hardness value used as dies, forming, and cutting that requires high hardness performance