Study of the tribological behavior of the Babbitt alloy – steel ABNT 1045 pair when varied thickness and roughness of the coating

ABSTRACT Babbitt, also known as patent metal or white metal, is a soft alloy widely used in sliding bearings that work in contact with steel, and has as base elements tin or lead, as well as intermetallic compounds usually formed by antimony and copper. The aim of this work was to evaluate the influence of the parameters roughness and thickness of the coating on the tribological behavior of the alloy when in contact with steel ABNT 1045. Tribological pin-on-disk tests were performed using ABNT 1045 steel pins and Babbitt-coated steel test specimens simulating the contact of a shaft on a Babbitt-coated bearing. The roughness and the thickness of the coating were varied in three levels, in order to observe the behavior in relation to the friction and the wear with the modification of these variables. In the tests that used test specimens with the smallest roughness within the analyzed range, an increase of 0.05 ± 0.02 to 0.46 ± 0.06 in the friction coefficient occurred when the coating thickness was raised from 0.45 ± 0.07 mm for 1.08 ± 0.17 mm. The highest coefficient of friction was observed in the test of the specimen with a higher coating thickness (1.08 ± 0.17 mm) and lower roughness (0.47 ± 0.01 μm), the highest wear was recorded in the test with the highest coating thickness and roughness (1.08 ± 0.17 mm and 1.29 ± 0.20 mm, respectively) and the lowest wear and friction coefficient were obtained by the test performed in the specimen with the least roughness (0.43 ± 0.03 μm) and medium coating thickness (0.45 ± 0.07 mm).

摘要 巴氏合金（Babbitt）又称专利合金或白合金，是一种以锡或铅为基体元素，通常还含有由锑与铜构成的金属间化合物的软质合金，被广泛应用于与钢质构件接触的滑动轴承中。本研究旨在评估涂层粗糙度与厚度参数，在与ABNT 1045钢接触时，对该合金摩擦学行为的影响。研究采用ABNT 1045钢销与涂覆巴氏合金的钢试样开展销盘摩擦学试验，模拟轴与巴氏合金轴承的接触工况。试验中将涂层粗糙度与厚度各设置三个水平，以观测这两个变量变化时的摩擦与磨损特性。在分析范围内采用最低粗糙度试样的试验中，当涂层厚度从0.45±0.07 mm提升至1.08±0.17 mm时，摩擦系数由0.05±0.02增至0.46±0.06。最高摩擦系数出现在涂层厚度最大（1.08±0.17 mm）且粗糙度最低（0.47±0.01 μm）的试样试验中；最高磨损量出现在涂层厚度与粗糙度均达最高的试验（分别为1.08±0.17 mm与1.29±0.20 mm）；而最低磨损量与摩擦系数则通过粗糙度最低（0.43±0.03 μm）且涂层厚度中等（0.45±0.07 mm）的试样试验获得。