Duplex hardening on SUS 304 with pack carburizing – nitriding process

The object of research: The object of research in this study is Austenic Sus 304 stains that are subject to surface treatment through the duplex hardening process using a combination of carburizing and nitriding package methods. This study specifically aims to evaluate the effect of the combination of this treatment on increased surface hardness of SUS 304 material and compare the effectiveness of three types of nitrogen gas cooling, namely welding grade (WG), high purity (HP), and ultra high purity (UHP), in the process of nitridation of violence and characteristics of the steel surface layer. Investigated Problem: The problem investigated in this study is the low violence and resistance of the Aus of Austenitic Rust Surf Sur Sur 304, which limits its use in certain industrial applications despite having excellent corrosion resistance. Therefore, this study examines how the combination of carburizing and nitriding surface treatment can effectively increase the surface hardness of the material. The process involves heating SUS 304 steel at 950°C for 36 hours using wood charcoal and barium carbonate as an activator. Followed by nitridation at 550°C for 30 hours with nitrogen gas. SEM/EDX and micro Vickers violent violence tests were carried out to evaluate the effectiveness of these applications. In addition, this study also investigated the difference in the effect of the use of three types of nitrogen gas with different levels of purity (WG, HP, and UHP) during the nitridation process on the results of increased violence and distribution of elements in the steel surface layer. The Main Scientific Results: The main scientific results of this study show that the process of carburizing and nitriding pack combinations significantly increases the violence of Austenic Sus 304 stainless steel surface, from 240 HV to a maximum of 1226 HV. This increase in violence is caused by diffusion of carbon and nitrogen elements into the material microstructure. Cooling using nitrogen ultra high purity (UHP) gas provides the highest result of violence compared to high purity (HP) and welding grade (WG). SEM/EDX analysis confirms the success of the diffusion of these elements up to the steel surface, which contributes to increasing the mechanical properties of the material surface layer. The area of practical use of the research results: The results of this study have the potential to be applied to various industries that use Austenitic Sus 304 rust steel, such as the chemical, food, biomedical, and automotive industries, where components are needed with high corrosion resistance as well as better wear and better resistance. The carburizing-nitriding package process developed can be used to improve the surface performance of engine components, medical devices, food processing equipment, and automotive parts, thereby extending the life and reducing the cost of maintenance and replacement of spare parts due to surface wear. Innovative Technological Product: Innovative technology products produced from this study are the surface treatment method of duplex hardening based on carburizing and gas nitriding gas combinations for austenitic stainless steel SUS 304, with a variety of different use of nitrogen gas (WG, HP, UHP). This method is able to significantly increase the hardness and resistance of the steel surface without sacrificing the corrosion resistance, thus creating a more durable and microstructured surface layer. This innovation has the potential to be applied in the production process of technical components that require a combination of superior mechanical properties and high corrosion resistance, such as in the automotive industry, medical devices, and manufacturing chemical equipment. Scope of the Innovative Technological Product: The scope of this technology product includes the application of the duplex hardening method through a combination of carburizing and gas nitriding gas processes in stainless steel Austenitic SUS 304 to increase violence, wear resistance, and stability of material surface microstructure. This method can be widely used in the manufacture of industrial engine components, medical devices, food processing equipment, as well as automotive parts and aircraft that require material with a combination of high mechanical properties and good corrosion resistance