Improvement of Friction and Wear Resistance for Ta or Ta+C Implanted H21 Steel

Ta and C ions extracted from a metal vapor vacuum arc ion source were implanted into H21 steel,with an implantation dose of 3×10^(17)cm^(-2),extraction acceleration 42kV,and average ion beam flux about 40μA.cm^(-2).Rutherford backscattering spectrum was used to measure the surface composition after Ta or Ta+C implantation.Observation of phase induced by Ta and C implantation was carried out by x-ray diffraction analysis.Experimental results showed that the wear rate of the implanted layer dropped 30%for Ta ion implantation and by a factor of 2.5 for Ta+C dual ion implantation.Thus Ta+C dual ion implantation was found to significantly reduce the friction coefficient of H21 steel.The wear mechanisms of the implanted layer were discussed.