Comparison of the nanoindentation results of two generation of powder metalurgy produced materials for plastic industry

This article analyses the properties and nanoindentation characteristics of the stainless PM steels M390 Microclean® and M398 Microcelan®. In a first part, the literature sources on PM steels, stainless steels and thermochemical treatment were studied in order to collect information on the problems that can be found in the thermal or thermochemical treatment of M390 and M398 to improve their mechanical and anticorrosion properties. Optical microscopy of both materials is presented to show the structure and get a more complex picture about them. The main reason for this article – the nanoindentation was performed on the Hysitron Triboindenter TI 950. For both samples, 7 indentation points were selected on the SPM scan – 4 for carbides and 3 for the base matrix. Based on the results, the nanohardness H and the reduced modulus of elasticity Er as well as the reduced modulus of elasticity of the phases ES were determined. The nanohardness H of the matrix corresponds to that of the ferrite, which confirms the material manufacturer\u27s specifications. The nanohardness of the carbides corresponds to the results of the other materials tested by CEDITEK

The Influence of Q & T Heat Treatment on the Change of Tribological Properties of Powder Tool Steels ASP2017, ASP2055 and Their Comparison with Steel X153CrMoV12

In connection with the growing importance of the efficiency and reliability of tools in industrial sectors, our research represents a key step in the effort to optimize production processes and increase their service life in real conditions. The study deals with the comparison of the tribological properties of three tool steels, two of which were produced by the powder metallurgy method—ASP2017 and ASP2055—and the last tool steel underwent the conventional production method—X153CrMoV12. The samples were mechanically machined with the finishing technology of turning and, finally, heat treated (Q + T). The study focused on the evaluation of hardness, resulting microstructure, wear resistance, and coefficient of friction (COF). The ball-on-disc method was chosen as part of the COF and wear resistance test. The tribological test took place at room temperature with dry friction to accelerate surface wear. The pressing material was a hardened steel ball G40 (DIN 100Cr6). Measurements were performed at loads of 10 N, 6 N, and 2 N and turning radii of 13 mm, 18 mm, and 23 mm, which represents a peripheral speed of 0.34, 0.47, and 0.60 m/s. The duration of the measurement for each sample was 20 min. The results showed that the COF of powder steels showed almost the same values, while a significant difference occurred with the increase of the radius rotation in the case of conventional steel. The results within the friction mechanism showed two types of wear, namely, adhesive and abrasive wear, depending on the Q + T process. From a tribological point of view in terms of wear, it was possible to state that the material ASP2055 after Q + T showed the lowest rate of wear of all the tested steels