Vpliv predgrevanja magnezijeve zlitine AZ80 na učinke laserskega pretaljevanja

Kranjc Požar, Peter (author), Šturm, Roman (mentor)

V teoretičnem delu naloge smo opisali osnovne značilnosti magnezija ter magnezijevih zlitin in njihovo uporabo in potencial v svetu. Opisali smo tudi osnovni princip delovanja laserjev, njihove lastnosti ter značilnosti Nd-YAG laserja. V praktičnem delu smo ugotavljali optimalne parametre nastavitve pulznega Nd-YAG laserja za dobro pretaljenost magnezijeve zlitine AZ80. Izbrani parametri so bili P = 28 W, v = 0,03 mm/s, f = 1 Hz, t = 10 ms, Db = 1,87 mm in brez dovoda zaščitnega plina. Nato smo pri teh parametrih opazovali vpliv predgretja pri treh različnih temperaturah: 20°C, 160 °C in 205 °C na dobljeno mikrostrukturo ter mikrotrdoto. Najbolje pretaljen in tudi najtrši površinski sloj smo dobili pri temperaturi 160 °C. Preverili smo tudi vpliv časa delovanja laserskega žarka, vendar rezultati niso pokazali vpliva tega faktorja.

• Language: Slovenian
• Keywords: laserji, Nd-YAG laserji, pretaljevanje površin, mikrotrdote, mikrostrukture, predgretja
• Work type: Final paper
• Typology: 2.11 - Undergraduate Thesis
• Organization: FS - Faculty of Mechanical Engineering
• Place of publishing: Ljubljana
• Publisher: [P. Kranjc Požar]
• Year: 2020
• Number of pages: XIII, 30 f.
• PID: 20.500.12556/RUL-114144
• UDC: 621.9.048.7:669.721.5(043.2)
• COBISS.SI-ID: 17057563
• Publication date in RUL: 19.02.2020

Secondary language

• Language: English
• Title: The influence of pre-heating of magnesium alloy AZ80 on the effects of laser remelting

Abstract

In the theoretical part of the thesis we describe the basic characteristics of magnesium and magnesium alloys and their use and potential in the world. We also describe the basic principle of laser operation, its properties and the characteristics of the Nd-YAG laser. In the practical part, we searched for the optimal tuning parameters of a Nd-Yag pulse laser for good melting of magnesium alloy AZ80. The parameters selected were P = 28 W, v = 0.03 mm/s, f = 1 Hz, t = 10 ms, Db = 1,87 mm and without protective gas supply. Subsequently, the effect of preheating at temperatures 20 ° C, 160 ° C and 205 ° C - on the microstructure and microhardness was observed in these parameters. The most molten and also the hardest surface layer was obtained at a temperature of 160 ° C. The influence of the laser beam travel time was also examined, but the results did not show the influence of this factor.

• Keywords: lasers, Nd-YAG lasers, surface remelting, microhardnesses, microstructures, preheatings