Development of surface characteristics of light weapon slide components to be made of AISI 4140 steels with nitrocarburization

In this study, it is aimed to minimize the negative effects such as friction, wear, fatigue, overheating and corrosion that occur in weapons during and after firing by nitrocarburization process. In this context, the AISI 4140 slide piece, which is one of the basic gun parts, has been brought to the best surface condition before the nitrocarburization process by optimizing the surface preparation processes. Twelve different nitrocarburization processes consisting of different temperature and time parameters were applied to the test samples. Afterwards, oxidation and sandblasting processes were applied to all test samples to increase corrosion resistance and to give them an aesthetic appearance. Surface roughness measurements were made after each surface treatment applied to the samples. After applying the surface treatments after nitrocarburization, hardness value measurement, metallographic examinations, wear tests, surface topography examinations were carried out. According to the results obtained, the most stable and homogeneous surface after sandblasting optimization was obtained in the samples blasted with S70 steel shot. It was observed that the composite layer thickness increased with temperature and time, while the rate of wear decreased as the composite layer value increased. It was determined that increasing in the diffusion layer also increased in direct proportion with the increase in time and temperature, but as the treatment time increased, the thickness increment rate decreased. After reaching a certain thickness, the increment rate in the diffusion layer decreased slowly; It was also observed that the hardness increased regardless of the diffusion.