Vpliv stopnje deformacije na mehanske lastnosti hladno vlečenega jekla PT929

Šavc, Peter (author), Fajfar, Peter (mentor)

Namen magistrskega dela je bil raziskati vpliv stopnje deformacije na mehanske lastnosti hladno vlečenega jekla PT929. Iz predhodno vroče valjanega in toplotno obdelanega kolobarja žice premera D = 8 mm smo vlekli palice različnih dimenzij in pri tem dosegali različne stopnje deformacij (0,09, 0,16, 0,32, 0,41, 0,48). S pomočjo nateznega preizkusa smo določili mehanske lastnosti jekla glede na stopnjo deformacije (mejotečenja, natezno trdnost,razteznost, kontrakcijo). Izvedli smo merjenje mikrotrdot in opravili metalografsko analizo s svetlobnim mikroskopom. Pri tem smo ugotovili, da povprečne izmerjene vrednosti mej tečenja, nateznih trdnosti in trdot z večanjem stopnje deformacije naraščajo.Padajo pa povprečne izmerjene vrednosti razteznosti in kontrakcije. Potrdili smo, da ima jeklo poboljšano martenzitno mikrostrukturo pred vlečenjem in po vlečenju. Dokazali smo tudi razogljičeno plast, ki je nastala pri predhodni izdelavi kolobarjev žice.

• Language: Slovenian
• Keywords: jeklo PT929, vlečenje, deformacijsko utrjevanje, mehanske lastnosti
• Work type: Master's thesis/paper
• Organization: NTF - Faculty of Natural Sciences and Engineering
• Year: 2020
• PID: 20.500.12556/RUL-119646
• COBISS.SI-ID: 31269891
• Publication date in RUL: 10.09.2020

ŠAVC, Peter, 2020, Vpliv stopnje deformacije na mehanske lastnosti hladno vlečenega jekla PT929 [online]. Master’s thesis. [Accessed 1 April 2025]. Retrieved from: https://repozitorij.uni-lj.si/IzpisGradiva.php?lang=eng&id=119646

Secondary language

• Language: English
• Title: The influence of deformation degree on mechanical properties of cold drawn PT929 steel

Abstract

The purpose of the master's thesis was to investigate the influence of the deformation degree on the mechanical properties of cold-drawn PT929 steel. From pre-hot rolled and heat-treated coils of wire with a diameter of D = 8 mm, rods of different dimensions were drawn, achieving different degrees of deformation (0.09, 0.16, 0.32, 0.41, 0.48). With the help of tensile test, we determined the mechanical properties of steel according to the deformation degree (yield strength, tensile strength, elongation, contraction). We performed microhardness measurements and metallographic analysis on a light microscope. We found that the average measured values of yield strength, tensile strengths and hardness increase with increasing strain ratehowever, the average measured values of elongation and contraction are decreased. We confirmed that the steel has martensitic microstructure before and after drawing. We also proved the decarburized layer formed during the fabrication of wire coils.

• Keywords: steel PT929, drawing, strain hardening, mechanical properties