C-SiC coatings were prepared on stainless steel with magnetron sputtering deposi-tion followed by Argon ion bombardment. These samples were implanted by 5 keV hydrogen ion beam. SEM, SIMS and IR transmission were utilized to study the mechanism and the stability of hydrogen retention of C-SiC coatings. Comparison was made between the samples with and without removing Argon by heating then followed by H+ ion implantation. The results show that removal of argon by heating can improve the hydrogen retention of the C-SiC coatings. The thermal stability of hydrogen barrier for the C-SiC coatings was investigated, it is found that the property of hydrogen retention for the C-SiC coatings is still good after heating at 573 K, but it becomes worse after heating at 873 K, and it loses after heating at 1 173 K.
