Laser-powder bed fusion (LPBF) is one of the preferred techniques for producing Co-Cr metal structures for dental prosthodontic appliances. However, there is generally insufficient information about material properties related to the production process and parameters. This study was conducted on samples produced from three different commercially available Co-Cr dental alloys produced on three different LPBF machines. Identically prepared samples were used for tensile, three-point bending, and toughness tests. Light microscopy (LM), scanning electron microscopy (SEM), and electron backscatter diffraction (EBSD) analyses of microstructure were performed after testing. Differences were observed in microstructures, which reflected statistically significant differences in mechanical properties (one-way analysis of variance (ANOVA) and Scheffé post hoc test (α = 0.05)). The material produced on the 3D Systems DMP Dental 100 had 24 times greater elongation ε than the material produced on the Sysma MySint 100 device and the EOS M100 machine. On the other hand, the material produced on the EOS M100 had significantly higher hardness (HV0.2) than the other two produced materials. However, the microstructure of the Sysma specimens with its morphology deviates considerably from the studied group. LPBF-prepared Co-Cr dental alloys demonstrated significant differences in their microstructures and, consequently, mechanical properties.

In this research, field and laboratory testing of three commercially available brake pads with the lowest, mid-dle, and highest price were performed. Complex field testing, where brake pads were tested in real extreme conditions on a loaded van vehicle and laboratory tests were performed. The field testing intended to investigate the temperatures that occur during the braking process and to determine the stopping distance, deceleration, and stopping time separately on the type of brake pads. Labo-ratory tests included the determination of the friction co-efficient according to ASTM G77, the structure of brake pad surfaces before and after the testing, and quantitative chemical analysis of brake pads. The aim of this study was to determine the influence of brake pad temperature on braking time depending on their purchase prices. The obtained results show a significant difference between the temperature, friction coefficient, chemical composi-tion, and braking time of the brake pads and their price.

This research explores how variations in laser powder bed fusion (LPBF) parameters—laser power (P), scanning speed (v), and base plate preheating temperature (ϑ_p)—affect the mechanical properties of the EOS Co-Cr SP2 dental alloy. A central composite design (CCD) was used to optimize the process parameters. Mechanical testing focused on crucial properties for dental applications, including yield strength (Rp_0.2), elongation (ε), toughness (KV_a), and flexural strength (R_ms). Microstructural analysis was conducted using light and electron microscopy, while XRD identified microstructural phases. Statistical analysis (ANOVA, Scheffé post hoc test, α = 0.05) revealed significant effects of P, v, and ϑ_p on the mechanical properties. Response surface models (RSMs) were developed, and optimal parameters were determined to achieve maximum toughness and flexural strength. Maximum values were obtained with laser power above 205 W and base plate preheating at 310 °C. The mathematical model predicted toughness values with less than 5% deviation from experimental results, indicating high accuracy.

This paper explores the influence of graphite shape, type, and dimensions on the thermal characteristics of Fe-C cast iron. Test samples were prepared from blocks of grey and nodular cast iron, specifically examining castings with D and A types of graphite as well as nodular graphite in a ferrite matrix. To analyze the effect of surface texture, sample surfaces were prepared with varying parameters of surface roughness, achieving values of 0.5 μm for polished and 12.6 μm for unpolished surfaces. Thermal characteristics, including thermal conductivity and effusivity, were evaluated using unsteady hot disk methods, with water as the contact agent, to simulate practical thermal conditions. Additionally, the microstructure of each sample was analyzed using optical microscopy. Results indicate that graphite content, type, shape, and surface roughness collectively have the most significant impact on the thermal properties of cast iron. This study’s findings provide valuable insights into optimizing cast iron for applications requiring efficient thermal management and highlight the importance of graphite morphology and surface finish in enhancing thermal performance.