Significant improvement of wear properties by creating micro/nano dual-scale structure in Al–Sn alloys

Improving wear performance of dual-scale Al–Sn alloys by adding nano-Si@Sn: Effects of Sn nanophase lubrication and nano-Si polishing

“…Details of the preparation of the NC Al-12 wt% Sn powder and the dual-scale structured Al-Sn alloys are provided elsewhere [9]. In that study, the CG regions of the dual-scale structured alloy were produced by preparing mixtures of coarse Al and Sn powder.…”

“…In the present study, the coarse Sn was replaced by a nano-Si@Sn composite. The alloys were prepared are as follows: (1) elemental Si powder was sealed in a stainless steel vial at a powder-to-ball ratio of 1:15, and milled for 4 h at 1000 rpm in a QM-3C shaker mill; (2) the milled Si powder was mixed with CG Sn powder in a weight ratio of 1:1 and then milled for 8 h at 800 rpm; this yielded a nano-Si@Sn composite powder comprised of nano-Si particles tightly wrapped in the nano-Sn phase; (3) CG Al was mixed with MA Sn-50Si (all percentages are by weight) powder in order to obtain an Al-nanoSi@Sn composite with a composition of Al-12Sn-12Si; (4) the Alnano-Si@Sn composite was mixed with the NC Al-12Sn powder in a weight ratio of 3:7; (5) a tri-modal Al-Sn-based bulk composite, denoted as CG-30-Si, was obtained by consolidating the mixtures under the same conditions reported in [9]. This alloy had a composition of 7.2 wt% MA Sn-50Si, 22.8 wt% CG Al, and 70.0 wt% MA Al-12Sn.…”

“…Significant improvements in the wear performance of Al-Sn alloys have recently been achieved by producing, via MA, dualscale microstructures consisting of soft, coarse-grained zones and hard, ultra-fine-grained (UFG) zones [9]. The enhanced wear resistance induced by the dual-scale structure is attributed to an adequate combination of hardness and toughness, originating from optimized matching between hard and soft regions.…”

Differentiated SnSb grain size distribution for improved tribological properties of Babbitt alloy

“…Compared to babbitt-c and babbitt-r, it can be seen from Figure 6 that the friction coefficient curves of babbitt-cr are relatively smooth with the increase of load from 5 N to 15 N. As the load increased, the fluctuation in the friction coefficient of babbitt-cr, which has a hybrid grain size, is smaller than the average friction coefficient of babbitt-c and babbitt-r. It shows that the nested distribution of coarse and refined grain is more resistant to crushing during sliding process, which can be attributed to the presence of many grain boundaries between refined grain and coarse grains (Lu et al , 2012). Meanwhile, considering the wettability of the surface of the specimens, oil film damage is different due to the different adsorption capacities of lubricated oil.…”

Phase evolution of binary immiscible Al–Sn film

“…Considering that components in Al-Sn alloy will be separated spontaneously due to the positive heat of mixing, high energy should be provided in the preparing process to fabricate homogeneous Al-Sn alloys. Based on this consideration, rapid solidification [10], mechanical alloying [11][12][13] and physical vapor deposition [14][15][16][17][18] are regarded as effective ways which can synthesize different metastable phases with homogeneous component distribution in immiscible alloy systems. During past decades, magnetron sputtering has been widely used to prepare homogeneous thin films of immiscible alloys [19][20][21].…”