20.500.12556/DKUM-85393 Vpliv nehomogenosti zaradi strjevanja gredice na obdelovalnost jekla 20MnV6 diplomsko delo The effect of inhomogeneity due to billet solidification on the machinability of 20MnV6 steel Obdelovalnost je sposobnost obdelave materiala z uporabo ustreznih rezalnih orodij in rezalnih parametrov. V Štore Steel d.o.o., ki je največji proizvajalec ploščatega vzmetnega jekla v Evropi, za določanje obdelovalnosti materiala uporabljajo ISO 3685. Izdelujejo tudi jeklo 20MnV6, ki ga kupec uporablja za izdelavo pritrdilnih matic vetrnic vetrnih elektrarn. Pri kontinuiranem litju gredice se zaradi načina hlajenja (ohlajanje v kokili in ohlajanje s pomočjo vodnih prh) ohlaja različno hitro, zato pride do pojava različne makrostrukture po prerezu gredice. Obdelovalnost jekla 20MnV6 smo skušali določati s pomočjo vrtanja. Podajalne sile vrtanja smo merili s piezo električno tehtnico sensocar scim proizvajalca Utež-sensoca. Za primerjavo smo uporabili analizo variance (ANOVA). Če so se med podajalnimi silami pojavile statistično značilne razlike, smo uporabili Tukeyev post-hoc test, s katerim pogledamo, med katerimi pari podajalnih sil so statistično značilne razlike. Ugotovili smo, da obstajajo statistično značilne razlike med podajalnimi silami pri vrtanju v posamične makrostrukture v gredici, pri vrtanju v gredice različnih šarž in da obstaja visoka korelacija med podajalnimi silami pri vrtanju ter rezultati določanja obdelovalnosti po ISO 3685. Tako obstaja možnost, da dolgotrajen in zahteven preizkus po ISO 3685 zamenja enostavni in hitri preizkus merjenja podajalnih sil pri vrtanju. Machinability is the ability to process materials with the help of suitable cutting tools and cutting parameters. At Štore Steel d.o.o, the largest manufacturer of flat spring steel, ISO 3685 is used to determine the machinability of the materials. In addition they also produce 20MnV6, which is used by the customer to make the fastening nuts of wind turbines. During the continuous casting of the billet, it cools at different rates, due to the cooling method (cooling within the mold and cooling using water sprays), resulting in the occurrence of different macrostructures across the cross-section of the billet. We attempted to determine the machinability of 20MnV6 steel using drilling. The drilling feed forces were measured using the piezoelectric scale "sensocar scim" by the manufacturer "Utež-sensocar". We used the analysis of variance (ANOVA) for comparison. If statistically significant differences appeared among the feed forces, we used the Tukey post-hoc test to determine which pairs of feed forces exhibited statistically significant differences. We found that there are statistically significant differences in the feed forces when drilling into individual macrostructures within the billet, when drilling into billets from different batches, and that there is a strong correlation between the drilling feed forces and the results of machinability determination according to ISO 3685. Thus, there is a possibility that the lengthy and demanding ISO 3685 test could be replaced by a simple and fast test measuring drilling feed forces. obdelovalnost določanje obdelovalnosti ISO 3685 struženje vrtanje podajne sile jeklo 20MnV6 kontinuirano litje makrostruktura analiza varianc ANOVA machinability determination of machinability ISO 3685 turning drilling feed forces steel 20MnV6 continuous casting macrostructure analysis of variance (ANOVA) true true false [M. Kač] Slovenski jezik Angleški jezik Diplomsko delo/naloga 2023-08-29 09:45:29 2023-10-05 08:29:23 2024-02-27 03:11:35 0000-00-00 00:00:00 2023 0 Maribor 0 Maribor 1 spletni vir (1 datoteka PDF (IX, 33 f.)) 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 620.179.5:669.14-147(043.2) 186806019 UN_Kac_Manuel_2023.pdf UN_Kac_Manuel_2023.pdf 1 9192D73F1CED41F01902B04BA2531C26 fdcdcf784ac54722229ac0c39cec2911557f77c86ddb2bcae5483e36120364b7 d5b70207-46b2-11ee-93d5-00155d000105 https://dk.um.si/Dokument.php?lang=slv&id=170817 Fakulteta za strojništvo 0 0 0