Evaluation Test of Oscillatory Sliding Bearing Materials in Seawater for the Multi-freedom Coupling Device of Multi-connected Floating Body..

Mega float等浮式结构物有望有效利用海洋空间，保护海洋环境。特别是由多个小型浮体单元组成的多连接浮体系统（MFBS），更是一个值得关注的问题。本研究的目的是评估轴承材料的摩擦学特性，并选择合适的材料，多自由度耦合装置的多连接浮体。对两种酚醛树脂、两种聚四氟乙烯、一种聚酰胺和两种铜合金等7种材料在海水、大气和海水-大气重复3种试验环境下与高耐蚀性的SUS 304（AISI 304）摩擦副进行了滑动磨损试验。（1）尼龙和铝青铜镶嵌石墨后，其比磨损率较低。从耐磨性和抗咬合性来看，这两种轴承材料都适用于联轴器装置。（2）酚醛树脂的比磨损率最高，轴的磨损量最大。这是由于树脂的热固化导致的局部磨粒磨损。（3）两种PTFE材料的摩擦系数都很低，但比磨损率却很高。(4)Pb青铜在大气中会在高摩擦系数和高温下产生咬合迹象。

Floating structures such as Mega float are expected to use the ocean space effectively and to preserve the ocean environment. Especially a multi-connected floating body system (MFBS) composed of many small scaled floating units is worthy of attention. The objective of this study is to evaluate the tribological characteristics of bearing materials and to select the suitable material for the multi-freedom coupling device of multi-connected floating body. Sliding wear tests of seven kinds of materials including two kinds of phenolic resins, two kinds of PTFE, a polyamide and two kinds of copper alloys rubbed against SUS304 (AISI304) of high corrosion resistance were carried out in three kinds of the test environments : in seawater, in the atmosphere and in seawater-atmosphere repeated condition.The main conclusions obtained are as follows.(1)Polyamide and Al bronze with embedded graphite and their shaft show low specific wear rate. The both bearing materials are suitable for the coupling device judging from wear resistance and anti-seizure.(2)Phenolic resins exhibit the highest specific wear rate and give the largest wear amount to their shafts in all the test specimens. It can be attributed to thermosetting of the resins resulting in partial abrasive wear.(3)Two kinds of PTFE exhibit high specific wear rate despite low friction coefficient.(4)Pb bronze in the atmosphere develops an indication of seizure with high friction coefficient and high temperature.