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为满足柴油机功率不断提高的要求必须研制性能更佳的轴瓦。这就促使开发(特别是用于小型高速柴油机的)高强度轴瓦合金。但同时还应考虑到材料的其他性能,如抗咬合性、嵌藏性以及抗蚀性等,以权衡合金的性能。本文研究了一些不同形式轴瓦的损坏实例包括穴蚀和微动磨蚀,同时还指出如何改进轴瓦的设计以满足当代柴油机的需要。在轴瓦材料发展过程中铝合金用得愈来愈多;这主要是由于它们具有较高的抗蚀能力。除了广泛用于汽车发动机的含锡20％的锡铝合金之外,又增加了含锡40％的铝基合金以改善抗咬合性。这种轴瓦在船用柴油机上用得更多。将通常含在其他锡铝合金中的1％的铜去掉可提高该合金的顺应性。但是在柴油机工作温度下合金的强度仍然大大高于白合金。目前正考虑采用含锡较多(50％以上)的铝基合金,并已获得了初步的使用效果。以前,只有铅青铜才具有足够的疲劳强度来承担增压高速柴油机连杆大端轴承的负荷。而含11％硅的铝基合金现在证实具有特别优良的综合强度和适应性。在这种合金内非常均匀地分布着硅晶粒。试验证明,抗咬合性和硅晶粒的大小有关。
In order to meet the continuous improvement of diesel engine power requirements must develop better bearing bush. This has led to the development of high strength bushings, especially for small high-speed diesel engines. However, other properties of the material, such as seizure resistance, embeddability and corrosion resistance, should also be taken into account to balance the performance of the alloy. In this paper, some damage cases of different types of bearing bush are studied, including cavitation and fretting. At the same time, the paper also shows how to improve the design of bearing bush to meet the needs of contemporary diesel engine. Aluminum alloys are used more and more in the development of bearing materials; this is mainly due to their high corrosion resistance. In addition to the tin-aluminum alloy containing 20% tin, which is widely used in automobile engines, an aluminum-based alloy containing 40% tin is added to improve seizure resistance. This type of bearing is used more on marine diesel engines. Removing 1% of the copper normally contained in other tin-aluminum alloys improves the compliance of the alloy. However, the strength of the alloy at the operating temperature of the diesel engine is still much higher than the white alloy. Al-based alloys containing more tin (over 50%) are currently under consideration and preliminary results have been obtained. Previously, only lead bronze had enough fatigue strength to take on the load on the big end bearings of the connecting rod of a supercharged high speed diesel engine. Al-based alloys containing 11% silicon now demonstrate exceptionally good overall strength and adaptability. Silicon grains are distributed very uniformly within this alloy. Experiments show that anti-seizure and the size of silicon grains.