Investigation of the physical and mechanical characteristics of the applied corrosion-resistant powder coating

This article presents the results of experimental work on the development of a laser complex for micro-and nanomodification of metal surfaces using hybrid technologies. As an alloying material, a corrosion-resistant composite powder of the national brand was chosen, which is used in industry to prevent the occurrence of corrosion formations on the working surfaces of the executive parts of machines. One of the most used national grades of structural carbon steels was chosen as the substrate. The parameters of the laser radiation varied in two parameters: scanning speeds in the range of 12-15 mm/sec and radiation power in the range of 3-5 kW. As a result of the work carried out under various power modes, prototypes were obtained. On their basis, tabular data on the obtained values of microhardness, wear resistance and friction coefficients are compiled. The description of the obtained results is given and the direction of further work is indicated.

A Study on the Machinability of Steels and Alloys to Develop Recommendations for Setting Tool Performance Characteristics and Belt Grinding Modes

This article presents a methodology for designing belt grinding operations with grinding and lapping machines. It provides the results of a study on the machinability of various steels and alloys with belt grinding, which are then classified according to an indicator that we have developed. Namely, cast aluminum alloys, structural alloy steels, structural carbon steels, corrosion-resistant and heat-resistant stainless steels, and heat-resistant nickel alloys have been investigated. The machinability index is the ratio of the performance indicators of the grinding belt and the depth of cut to the indicators of grade 45 structural carbon steels (similar to steel AISI 1045) and similar steels and alloys. The performance indicators of the grinding belt are chosen from a set of calculated and estimated indicators. Experimentally determining the dependences of the performance indicators on the belt grinding modes and conditions, taking into account the established levels of machinability, allowed us to develop recommendations for designing belt grinding operations with grinding and lapping machines. The proposed methodology for designing belt grinding operations guarantees optimal performance and ensures that the necessary quality of the machinable surfaces is achieved. At the same time, it takes into account variable machining conditions, which change within specified limits.

Detection and Monitoring of Corrosion in Structural Carbon Steels Using Electromagnetic Sensors

An electromagnetic sensor was assessed as a possible instrument for nondestructive detection and monitoring of corrosion in structural carbon steels. In this study, the magnetic response of three structural carbon steel rods (AISI 1018, AISI 1045, and AISI 1045-High Mn), was evaluated in the as-received (uncorroded) and corroded conditions. Initially, the material was systematically machined out from each steel rod, followed by the magnetic evaluation of each specimen. Other set of metal rods were exposed to uniform corrosion and later examined by the electromagnetic sensor. Correlations have been established between the degree of mass loss and magnetic response of the test specimen. Based on the results, it can be said that the electromagnetic sensor has the potential to be used as a reliable nondestructive tool to detect corrosion at early stages based on the variation in magnetic properties. A metallurgical analysis of all test rods was also undertaken, which showed that microstructures have an important effect of the magnetic properties of the steels.