Studi Pengaruh Implantasi Ion Karbon Terhadap Kekerasan Permukaan Baja Aisi 1040.

Surface modification using an ion implant method has already been proven as one of the method for surface hardening. The aims of this research is to learn how the effect of ion intensity and impact energy to the hardness of the specimens made of medium carbon steel AISI 1040. The intensity of ion was varied from 0.83, 1.67, 2.5, 3.33, 4.17 up to 5 (x 1017 ion/cm2), but the impact energy was varied from 30, 40, 50, 60, 70 up to 80 (keV). After giving all combination of treatment, each of them were tested on micro hardness tester to see the different. To reduce the cost in order to see the depth of the ion penetration on the surface of specimen, the hardness distribution across the thickness only applied for the best result of combined treatment. The medium carbon steel AISI 1040, initially has chemical component C ± 0,4 %, and body centered cubic (feritperlit) structure, with 286 KHN in hardness, but after ion implant it increase up to 560 KHN which was reached on ion intensity 3.33 x 1017 ion/cm2, and impact energy 70 keV. At that condition, the thickness of hard layer of iron-carbide was about 0.5 mm, and the concentration of C varied along the thickness, and at the hardest layer, the concentration of C was ± 26.8 %. Key words : ion implant, ion intensity, impact energy, depth of penetration, hardness distribution, composition distribution