Welding is a fundamental technique for joining materials in industrial applications and large-scale construction. Various methods are employed to ensure robust connections. Resistance spot welding is ideal for thin sheets due to its speed, low cost, short processing times, and easy integration into automation systems. Stainless steel is widely used in many food and beverage industries because of its durability and ability to withstand diverse conditions. However, despite the existence of modeling approaches, predictive models linking weld parameters to the simultaneous improvement of stiffness and tensile strength in different joint regions remain limited in published studies. Many studies treat the weld as a single homogeneous region or focus primarily on general indicators such as tensile strength or weld diameter. The spatial variation in properties between the weld region, the heat-affected region, and the base metal is often not modeled separately. This study examines the effect of welding current and welding time on the mechanical properties of weld beads. Scanning electron microscopy (SEM) was also used to characterize the weld microstructure. The combination of mechanical evaluation and microstructural analysis provides deeper insight into the relationship between welding parameters and weld quality. Among the conditions studied (6–8 kA, 60–120 ms), the optimal parameters (6 kA, 120 ms) produced the maximum hardness of 178.16 HV observed in the weld zone and a tensile strength of 12 kN. The experimental results demonstrated that welding parameters significantly influence weld bead quality, and the optimization study allowed us to identify the parameters that achieve the best possible mechanical properties and optimal operating conditions. The experimental results demonstrated that welding parameters significantly influence weld bead quality, and the optimization study using Response Surface Methodology (RSM) allowed us to identify the parameters that achieve the best possible mechanical properties and optimal operating conditions.

The emergence of new hard and extra-hard materials has led to the development of new technologies capable of processing them, known as unconventional technologies. Electrical discharge machining (EDM) is a very common unconventional technology in the manufacturing industry, used to process special materials. The primary benefit is the ability to machine various complex shapes at a reduced cost. This study addressed the use of intensive machining regimes that would enhance productivity while also maintaining a high quality of the resulting surface. The experimental setup was designed according to a D-optimal response surface method, and the results were statistically processed using ANOVA. The results revealed that it is possible to achieve both high productivity and good surface quality, but it was also found that increasing the processing parameters is feasible only to a certain extent.

The purpose of any electrode in die-sinking EDM is to transmit electrical impulses that facilitate workpiece erosion with minimum or no self-erosion. The performance of the electrode depends on the properties of the material that it is made of, application, and the workpiece material. This study focused on employing intensive machining regimes that increase productivity while maintaining electrode wear as low as possible to enhance cost-effectiveness. The experimental tests were organized using the response surface method and the analysis of the results is based on the ANOVA method. The findings revealed that the WCu 75/25 outperforms the other two in wear resistance and CuZn39Pb2 is the most wear prone. It was revealed that WCu 75/25 electrode at Ip ≈ 90 A and Ton between 360 and 390 µs represents the globally best solution for a minimum wear.

The aim of the paper is to present the actual state of techniques regarding the influence of cryogenic cooling in turning and milling process. Processing some materials is impossible without cooling the tool or the processed material. Hard-to-cut materials are increasingly used in industry, so new methods of cooling these materials had to be researched. Cryogenic cooling is the most efficient method to cool down the turning, milling or cutting tools. There are a lot of materials that are not affected by the low temperature of the liquid nitrogen (LN ₂ ), on the contrary, they behave better and have better proprieties after being cooled with LN ₂ . On the other hand, there are materials that do not behave very well after cooling them with LN ₂ because their properties are changed, but with the right equipment, the amount of cooling liquid can be controlled, so that the temperature could be maintained at an optimal level. This paper highlights the advantages of the cryogenic cooling systems compared to the classic cooling systems (cooling and lubricating in the same time) industrially used.