GCr15 steel was implanted with N\++ ions by
ion implantation technique.The structure and
contacting fatigue resistance of
GCr15 steel after N\++
ion implantation is studied by means of orthogonal experimentation. The
contacting fatigue resistance of GCr15 steel were examined on a JP 52 contacting fatigue tester.The phase composition and the mechanisms of the modified surface were investigated by means of scanning electron microscopy (SEM),transmission electron microscope(TEM), auger electron spectroscopy(AES),and X ray photoelectron spectroscopy(XPS).The results showed that the physical and mechanical properties,as well as the chemical properties,of the surface layers are greatly changed by ion implantation.Such as decreases in surface roughness,increases in microhardness accompanied with compressive stress,and a quantity of finely dispersed hard secondary phase particles(ε Fe 2 3 N etc ) coexisting with the matrix structure were formed in the nitrogen implanted surface film.The contacting fatigue resistance is considerably increased. The extent of the improvement in the contacting fatigue resistance of GCr15 steel is not proportional to the concentration of N + implanted into the steel.It seems to have a optimum value of N + implantation dose and energy in order to improve the contacting fatigue resistance of GCr15 steel.The orthogonal analyses give the optimum implantation parameter:fonnd by orthogonal analyses is to be dose of 4×10 17 ions/cm 2 at energy 100keV for GCr15 steel.