X6Cr17 steel, also known as AISI 430 or W. Nr. 1.4016, belongs to the group of ferritic stainless steels characterised by a chromium content of 16 to 18 wt. %.
The purpose of this thesis was to determine the most suitable combination of hot rolling and subsequent heat treatment for X6Cr17, W. Nr. 1.4016, produced in the form of heavy‑gauge steel plate in the widest formats in the product range of SIJ Acroni d. o. o. The objective of the research was to achieve the required mechanical and microstructural properties of annealed stainless-steel plate, as specified in the SIST EN 10088-2:2015 and ASTM A240/240M-14 standards, by optimising the technological parameters of hot rolling and heat treatment. Emphasis was placed on achieving and improving the tensile strength Rm and elongation A50, which were limited or even inadequate for the standard heavy-gauge steel plate during processing.
As part of the experimental work, in addition to industrial hot forming, several different laboratory heat treatments were performed on samples of previously hot-rolled thick plate to investigate the effect of temperature on the final properties of the material. The investigations included conventional annealing at temperatures ranging from 770 °C to 830 °C. The influence of the individual heat-treatment conditions in combination with prior hot rolling was evaluated based on the resulting mechanical properties and changes in the microstructure.
The highest tensile strength values, Rm of 517 MPa and 531 MPa, and elongation values, A50 of 29,5 % and 30,5 %, were measured on samples in which processing was interrupted before the final passes of hot rolling, followed by annealing at 830 °C for 30 hours with furnace cooling.
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