The impact of soot primary nanoparticles affecting metal wear was investigated. The commercial Carbon Black (CB) with different primary particle sizes were mixed with the engine oil for simulating soot contamination. The physical properties of carbon black including density and hardness were calculated using Transmission Electron Microscopy (TEM) image analysis. The metallic wear test was evaluated by using a Four-ball wear tester. After the tests, the ball surfaces were inspected by utilizing High-Resolution Optical Microscope (OM), Scanning Electron Microscope (SEM) and Energy Dispersive X-ray spectroscopy (EDX) analysis. Based on a Four-ball wear test, the 1 % by weight of carbon black contamination shows a bit higher average wear scar diameter (WSD), but the surface roughness is reduced. SEM micrograph of metallic wear scar for the engine oil without soot shows the area of grooves, plastic deformation and subsurface crack. On the other hand, when carbon black is added to the oil, it can be seen that there are many deep grooves along with the sliding direction. The relationship of calculated oil film thickness, primary nanoparticle size distribution, carbon atom density of soot and hardness is clearly explained metallic wear mechanisms.

中文翻译：

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电子显微镜图像分析烟尘粒度对四球金属磨损的影响

研究了烟灰初生纳米颗粒对金属磨损的影响。将具有不同主要粒径的商品炭黑（CB）与发动机油混合，以模拟烟灰污染。使用透射电子显微镜（TEM）图像分析计算了炭黑的物理性能，包括密度和硬度。通过使用四球磨损测试仪评估金属磨损测试。测试后，通过使用高分辨率光学显微镜（OM），扫描电子显微镜（SEM）和能量色散X射线光谱（EDX）分析来检查球的表面。根据四球磨损试验，重量百分比为1％的炭黑污染物显示出更高的平均磨损痕迹直径（WSD），但表面粗糙度降低了。不含油烟的机油的金属磨损痕迹的SEM显微照片显示了沟槽的面积，塑性变形和表面裂纹。另一方面，当将炭黑添加到油中时，可以看出沿着滑动方向有许多深沟槽。计算出的油膜厚度，初级纳米颗粒尺寸分布，烟灰的碳原子密度和硬度之间的关系清楚地说明了金属磨损机理。