Comparative study on wear behaviour of magnesium and aluminium alloys

Abstract

Magnesium is the lightest metal used in structural applications, such as aerospace industry, and therefore, it provides the greatest potential for weight or energy reduction. It is particularly suitable for transport technology applications. In order to substitute aluminium alloys in aeronautical engines, wear behaviour of magnesium alloys is considered. A comparison of the unlubricated wear resistance of an aluminium alloy (A 357) and two magnesium alloys (AZ 91 and WE 43) rubbed against 52 100 bearing steel in a pin-on-ring configuration over a range of sliding speed (1 -7 m/s) and applied normal loads (20 -80 N) is established. In addition to the measurement of the friction force and wear depth, the temperature near the sliding contact is also measured using a thermocouple placed at the back of the pin sample. Thermal effect on friction and worn surfaces are observed and characterized. Wear transitions are found for the AZ 91 and the A 357 alloys. These transitions are controlled by critical temperatures at the contact surfaces. Scanning electron microscopy observations and profilometric analyses are conducted to confirm these transitions and identify the wear mechanisms.

Sliding Wear Characteristics of AZ91D Alloy at Ambient Temperatures of 25–200 °C

“…The wear rate at 200°C was lower than those at 25 and 100°C under the loads of 12.5-25 N, but vice versa under the loads of more than 25 N. More important, under a load of 25 N or below, the wear at various ambient temperatures fell in mild wear. This seems not to be in agreement with the popular view that the transition from mild-to-severe wear is controlled by the critical surface temperature [1][2][3][4][5]. It is clear that the surface temperature in this mild wear regime under the ambient temperature of 200°C was substantially higher than the reported critical surface temperature (74°C) reported by Chen and Alpas [1].…”

“…They pointed out that the transition from mild wear to severe wear was controlled by the critical surface temperature. The subsequent researchers almost shared the same view [2][3][4][5]. An et al [3] investigated the dry sliding wear of AZ91 alloy against a high carbon chromium steel under the loads of 20-380 N and a sliding velocity of 0.785 m/s.…”

“…A small number of recent studies investigated the wear behaviors of magnesium alloys [1][2][3][4][5][6]. Chen and Alpas [1] studied the dry sliding wear of AZ91 alloy against an AISI 52100 bearing steel.…”

Effect of B4C reinforcement and hot rolling on microstructure and mechanical properties of WE43 magnesium matrix composite

“…9 In addition to good mechanical properties, these alloys have a good aging response, corrosion resistance, and wear resistance compared to other Mg and Al alloys. 10,11 Nevertheless, researchers are still looking for ways to improve the comprehensive mechanical properties of WE series alloys.…”

Dry sliding wear performance of 7075 Al alloy under different temperatures and load conditions

“…As the contact temperature surpassed a critical value (about 0.4 times melting point of alloy), the mild-to-severe wear transition occurs. The above wear mechanisms and mild-to-severe wear transition criterion were popularly accepted by subsequent researchers [9][10][11][12]. For aluminum as a high oxidation active metal, oxidation is inevitable during wear.…”