Effect of size and area ratio of primary silicon phase in hyper-eutectic Al–Si alloys on wear under the lubricated condition

Abstract

The wear behavior of hyper-eutectic Al-Si alloys against bearing steels was investigated under the lubricated condition. The severe-mild wear transition of hyper-eutectic Al-Si alloys occurred when Si-particle size or area ratio exceeded critical values. Below the critical value, Al-Si alloys still remained in the sever wear mode resulting in a large amount of wear due to the insufficient sparse distribution of primary Si phase at the contact area.

Running-in for Low Friction between Silicon-Containing Aluminum Alloy and Bearing Steel in Engine Oil

“…However, increasing the silicon content in aluminum alloy is practically challenging. The change in the silicon content causes deterioration of the machinability, casting characteristics, and thermal expansion properties of the aluminum alloy [14,23]. Additionally, an increase in the silicon content causes crack initiation around the boundaries of silicon grains [24].…”

“…Some authors have reported that the friction and wear properties of silicon-containing aluminum alloys improve through the reduction of friction and/or wear, known as running-in [23,26]. For example, Shioda et al [23] reported that by controlling the size and area ratio of the silicon grains, the friction system between bearing steel (AISI52100) and siliconcontaining aluminum alloy could exhibit running-in without an increase in the silicon content.…”

“…Some authors have reported that the friction and wear properties of silicon-containing aluminum alloys improve through the reduction of friction and/or wear, known as running-in [23,26]. For example, Shioda et al [23] reported that by controlling the size and area ratio of the silicon grains, the friction system between bearing steel (AISI52100) and siliconcontaining aluminum alloy could exhibit running-in without an increase in the silicon content. Additionally, Stoyanov et al [26] reported the formation of a mechanical-mixing layer on the worn surface of silicon-containing aluminum alloy only under a high-load condition, which contributed to the appearance of running-in behavior.…”