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New Mg-3Zn-2Ca magnesium alloy was prepared using different processing techniques: gravity casting as well as squeeze casting in liquid and semisolid states. Materials were further thermally treated; thermal treatment of the gravity cast alloy was additionally combined with the equal channel angular pressing (ECAP). Alloy processed by the squeeze casting in liquid as well as in semisolid state exhibit improved plasticity; the ECAP processing positively influenced both the tensile and compressive characteristics of the alloy. Applied heat treatment influenced the distribution and chemical composition of present intermetallic phases. Influence of particular processing techniques, heat treatment, and intermetallic phase distribution is thoroughly discussed in relation to mechanical behavior of presented alloys.

The paper presents an investigation of the effect of process variables and material condition on the forgeability of magnesium wrought alloys of the Mg-Al-Zn group. The experimental work included the studies of forging capabilities of the alloys in open-die forging at hot-and warm-working temperatures. Forging tests were performed for the material in both the as-cast and as-worked conditions, for two variants of the work-piece geometry. Different variants of the work piece indicated fracturerelated problems in forging magnesium alloys in the warm-working temperature mode, which involved an interaction between the material composition and process variables, and the state of stress. By means of numerical calculations it was concluded that, in addition to the material condition, the favourable state of stress, provided by a closed die, could greatly improve the formability of magnesium alloys in the warm-working range. Keywords: forging, magnesium alloys, automotive applicationŝ lanek predstavlja preiskavo vplivov procesnih spremenljivk in materiala na kovnost magnezijevih zlitin iz skupine Mg-Al-Zn. Eksperimentalno delo je vklju~evalo {tudij sposobnosti za kovanje zlitin v odprtem orodju pri temperaturah vro~ega in toplega preoblikovanja. Preizkusi kovanja so bili izvr{eni za material v litem stanju in za`e predelan material za dve vrsti izkovkov z razli~no geometrijo. Razli~ne variacije izkovkov so pokazale pri kovanju magnezijevih zlitin te`avo z razpokami pri toplem preoblikovanju ter interakcijo med sestavo materiala, procesnimi spremenljivkami in stanjem napetosti. Z numeri~nimi izra~uni je bilo ugotovljeno, da dodatno k razmeram materiala lahko ugodno stanje napetosti, ki se ga dose`e z zaprtim orodjem, mo~no izbolj{a preoblikovalnost magnezijevih zlitin v obmo~ju toplega preoblikovanja. Klju~ne besede: kovanje, magnezijeve zlitine, uporaba v avtomobilski industriji

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