ABSTRACT
Abstract-The effect of residual stresses and their evolution during annealing were investigated on steel specimens coated with thin, hard coatings. Amorphous hydrogenated silicon carbide and amorphous silicon-containing diamond-like carbon (Si-DLC) thin coatings were deposited on AISI 4340 low alloy steel specimens. The respective deposition methods used were plasma-enhanced chemical vapor deposition and Ar+ ion beam-assisted physical vapor deposition of tetraphenyltetramethyl-trisiloxane (704 Dow Coming diffusion pump oil). During annealing in an argon atmosphere the residual stress attributed to hydrogen entrapment during deposition gradually changed from compressive to tensile due to loss of hydrogen. The rate of stress increase decreased with increasing annealing time. The cohesion and adhesion failure loads and the abrasive wear resistance decreased with increasing annealing time, as did the friction coefficient between the coating and a diamond stylus.
