Contribution to the study of the Al-Zn phase diagram

Abstract

Calorimetric measurements in the AI-Zn system rule out the existence of an O?'-phase and of a second monotectoid reaction at 340 ~ .Two types of phase diagrams have been published for the AI-Zn system [1]; they differ in the presence or absence of the e" phase and of two reactions, a monotectoid one at 340 ~ and a peritectic one at 443 ~ (Fig. 1). For the second monotectoid r~action,two different temperatures are proposed : 275 ~ or 236 ~ [2]. The ~-phase is face-centred cubic and the/3-phase hexagonal compact; the phases ~' and e" are also fcc and differ in their lattice parameters by as little as 0.001 A 13]. It is believed that due to this very minor difference the transformation at 340 ~ cannot be observed, but many authors still use the diagram presented by Fig. 1 [4].

High-performance joining technology for aluminium matrix composites using ultrasonic-assisted brazing

“…In order to create ceramic reinforcements in the bond region from MMC parent materials using ultrasonic agitation, the layers in the parent materials close to the bond region need to form a liquid state before the ultrasonic mixing process. According to the Zn–Al phase diagram [29], the Zn–Al alloy will liquefy when Zn concentration exceeds the liquid–solid phase boundary. At 500°C, the Zn–Al alloy will start to liquefy if the Zn concentration increases over 42 wt-%.…”

Formation, control and functionalization of nanoporous zinc by selective corrosion of Al–Zn alloys with varying compositions

“…1 and S2 †). 37 As shown in Fig. 1, the RS Al 96 Zn 4 and Al 92 Zn 8 alloys display a single-phase feature with a grain size of 4-8 μm.…”