In this study, low-carbon cast steel was reinforced with TiC by SHS-B method, also known as combustion synthesis during casting method. The composite zone was then subjected to surface remelting by Gas Tungsten Arc Welding (GTAW) method. The remelting operation was realized manually, at 150 A current magnitude. Microstructure, phase composition and hardness of remelted zone were investigated. XRD results reveal that the phases of the composite zone in initial state consist of TiC and Feα. Surface remelting resulted in formation of thick layers containing TiC carbides, Feα and Feγ. Microstructural examination has shown strong refinement of titanium carbides in remelted zone and complete dissolution of primary titanium carbides synthetized during casting. The average diameter of carbides was below 2 μm. The structural changes are induced by fast cooling which affects crystallization rate. The hardness (HV30) of the remelted layer was in the range between 250 HV and 425 HV, and was lower than hardness in initial state.

A method of using the electric charge in a capacitor was applied for the manufacture of thermocouple micro-joints. The motivation for the study was the need to produce a stable welded connection without affecting the geometry of the substrate, which was a thin sheet of Inconel 625 alloy (UNS designation N06625). Within the framework of the research work, a suitable workstation for micro-joints elaboration was built and welding experiments were performed using different electric charges. Studies carried out within the framework of the present work have shown that joints based on Inconel 625 alloy and platinum have the best application properties in the range of small-scale temperature measurements. They can be used, e.g., for monitoring the temperature distribution on the inner surfaces of electric motor casings. An undeniable advantage is in this case the high thermal resistance of both materials used to produce the joint, i.e. the Inconel 625 alloy and platinum. This allows them to be used at high temperatures under atmospheric conditions.

The effect of vanadium microaddition on the strength of low-carbon cast steel containing 0.19% C used, among others, for castings of slag ladles was discussed. The tested cast steel was melted under laboratory conditions in a 30 kg capacity induction furnace. Mechanical tests were carried out at 700, 800 and 900°C using an Instron 5566 machine equipped with a heating oven of  2C stability. Non-standard 8- fold samples with a measuring length of 26 mm and a diameter of 3 mm were used for the tests. It has been shown that, compared to cast steel without vanadium microaddition, the introduction of vanadium in an amount of 0.12% to unalloyed, low carbon cast steel had a beneficial effect on the microstructure and properties of this steel not only at ambient temperature but also at elevated temperatures when it promoted an increase in UTS and YS. The highest strength values were obtained in the tested cast steel at 700C with UTS and YS reaching the values of 193 MPa and 187.7 MPa, respectively, against 125 MPa and 82.8 MPa, respectively, obtained without the addition of vanadium. It was also found that with increasing test temperature, the values of UTS and YS were decreasing. The lowest values of UTS and YS obtained at 900°C were 72 MPa and 59.5 MPa, respectively, against 69 MPa and 32.5 MPa, respectively, obtained without the addition of vanadium.