Magnesium-alloy die forgings for automotive applications

Abstract

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

Characterization of Ni-P coating prepared on a wrought AZ61 magnesium alloy via electroless deposition

“…They find their application in the automotive and aerospace industry. [1][2][3][4] A high chemical reactivity, low corrosion resistance and low hardness are their negative properties. 4 Therefore, it is necessary to protect magnesium alloys against the effects of external environment.…”

“…[1][2][3][4] A high chemical reactivity, low corrosion resistance and low hardness are their negative properties. 4 Therefore, it is necessary to protect magnesium alloys against the effects of external environment. There are several ways of protecting magnesium alloys such as galvanic or electroless deposition of coatings, conversion coatings, organic coatings and varnishing.…”

Mg-Alloys for Forging Applications—A Review

“…Both types of precipitation are shown in Figure 7. The increasing material strength with rising Al content has also been confirmed in a comparative study of AZ31, AZ61 and AZ91 done by Madaj et al [40]. Two different geometries, a piston rod and a plate, were forged, heat treated and analyzed by hardness measurements.…”

“…These studies are briefly described above, in Section 5.1.1 for AZ31. Madaj et al [40] describes the forming behavior of AZ61 at a material temperature of 320 • C in a work comparing the formability of AZ31, AZ61 and AZ91, which is discussed in Section 5.1. A comparison of forging behavior and mechanical properties of AZ61, AZ80 and various TAZ alloys by Yoon and Park [71] is reviewed in Section 9.…”

Fatigue life improvement of cast ZK60 Mg alloy through low temperature closed-die forging for automotive applications

“…Among different manufacturing techniques, forging is of particular interest not only because it can lead to enhanced mechanical properties, but also it can form components with complicated geometries [9] [10]. The monotonic and cyclic behaviour of different open dieand semi-closed die forged Mg alloys have been investigated so far [11]- [19].…”