The fabrication of lightweight and high-strength composite materials has played a major part in improving environmental protection, reducing emissions, and enhancing the mechanical and tribological properties of products intended for use in industrial machinery and transportation manufacturing.
Due to their good low density, wear resistance, fatigue strength, high load-carrying capacity, thermal conductivity, excellent corrosion resistance, and overall low price when compared to other materials, aluminum metal matrix materials (AMMCs) have become one of the most common choices for materials used in a variety of industrial sectors [
1,
2,
3,
4,
5]. To improve the strength and wear resistance of AMMCs, different types of reinforcing phases (RPs) are introduced. The most common RPs are silicon carbide (SiC) [
6,
7,
8], alumina (Al
2O
3) [
8,
9,
10], graphite [
11], zirconium silicate [
12], titanium carbide [
13], and boron carbide [
14]. Since its high thermal stability and brittle phase do not appear between the RP and the metal matrix, alumina can be viewed as a well-suited choice for reinforcement [
15].
An investigation of the wear properties of composites obtained via powder metallurgy with AA7075 as the base alloy and reinforced with 5 wt% Al
2O
3 particles with sizes varying between 0.3 and 15 µm under dry sliding conditions concluded that the sample with the largest RP particle size demonstrated the best wear resistance. In addition to this data, using analysis of variance (ANOVA) has shown that the most significant parameter influencing volume loss is the load [
15].
The wear properties of AMMCs obtained by a liquid processing method from AA242 reinforced with 30 vol% of alumina particles were investigated, and the results indicated that, when increasing the wear load, the wear rate increased and the coefficient of friction (COF) decreased due to the removal of the RP [
16]. Due to its better thermal dissipation, the tribological performance under of an AA6061 composite reinforced with alumina sub-micron particles under dry sliding conditions indicated a lower wear rate when compared with grey cast iron [
17].
Babbitt alloys are one of the most studied wear-resistant alloys and one of the most common materials intended for application in bearings [
18,
19,
20]. Tin-based babbitts are casting alloys with a multiphase microstructure, most commonly characterized by SbSn and Cu
6Sn
5 intermetallic compounds and a solid solution matrix [
21,
22,
23,
24,
25]. The tin-based babbitt is plastic and soft, carrying the particles of hard phases, which provide effective abrasion resistance [
20,
21,
22,
23]. Due to the presence of β-phase particles in tin babbitts with up to 20 wt% antimony, the hardness of these alloys has been observed to increase without deteriorating the sliding wear behavior [
21,
24]. The effect of antimony in tin-based white metals varying between 5 and 23 wt% on the amount of wear in lubricated wear testing has also been studied, with results indicating that 18 wt% antimony is the limit at which the wear resistance of the alloy is not affected [
24]. Due to its low COF and high fracture toughness, cast commercial babbitt grades B88, B83, and B83C with tin bases are used as antifriction materials in a variety of engineering applications [
26]. Also, due to its soft plastic base and large hard second-phase inclusions, and according to the Charpy rule, the tin-based babbitt possesses a low COF [
23]. The production of dispersion-hardened heterogeneous tin-based babbitt composites leads to overcoming a drawback such as the low fatigue resistance due to the sharp angles of SnSb intermetallics [
27]. A study suggests that the inclusion of 10 wt% of alumina reinforcement in Sn–Sb–Cu babitt alloy improves the wear resistance of the material [
28]. In another investigation, three types of hard particles with different densities and identical shapes such as Al
2O
3, Cr
3C
2, B
4C were blended with tin-based babbitt alloy and the results from the tribological tests indicate that combination of babitt and alumina shows the lowest coefficient of friction [
29].
The incorporation of nanoparticles as reinforcement in the babbitt alloys has been proven by various studies [
30,
31] as an improvement in tribological and mechanical properties in the nanocomposites. A study focused in investigating the influence of alumina nanoparticles on microstructural variation of tin-based babbitt as well as bimetallic microstructural interface suggest that the addition of 0.25 and 0.50 wt% alumina nanoparticles improves the mechanical and tribological properties and affects the morphology and distribution of Cu
6Sn
5 hard phase in the solid solution of the nanocomposite [
30]. The results presented in another study of white babbitt coatings modified by carbon nanotubes show increase in the wear resistance of tested materials [
31].
The aim of the present research is structural and chemical characterization of an advanced composite material in addition to the study of the effect of different loads on the tribosystem interaction parameters such as mass wear, specific wear rate, and coefficient of friction, of an advanced composite material with enhanced wear resistant properties under dry sliding conditions. The advanced composite consists of an aluminum–Al
2O
3 skeleton produced by a replication method, which is commonly utilized for the production of high-porosity metal materials with an open-cell structure and it is infiltrated by tin-based babbitt [
20]. Analyzing the literature, the production and investigation of no such advanced composite material was found. The tribological characterization was conducted under different conditions, especially 40, 50, 60 N loads. These conditions were not presented in the literature by other authors investigating tin-based babbitt alloys reinforced with micro- or nanoparticles [
27,
28,
29,
30,
31].
The combination of the low density, fatigue strength, high load-carrying capacity, thermal conductivity, excellent corrosion resistance, and overall low price of the AMMCs with the self-lubricating properties and load-carrying ability of the tin-based babbitt could represent a potential practical application for the manufacturing of sliding contact bearings. This study is a continuation of our previous research [
32,
33], and the results of the observed tribological behavior of the advanced composites are compared with the results of the B83 babbitt with different loads and under the same dry sliding conditions.