Study On Friction, Wear And Lubrication Of The Mated Couple Of HIP-Si₃N₄/GCr15

Traditional study of friction concentrated on the mated couple of metal materials, the couple is tested in the different conditions and the friction parameters are obtained , the lubrication is used sometimes in the test to improve the friction performance. However, for hybrid mated couple of material (metals and nonmetals), especially for mated couple of metal and ceramics, nearly nobody researches them in our country, the research of their friction mechanism hasn't filled the gaps in science and technology of our country. With the development of material and machinofacture technology , the mated couple of metals can't meet the requirement of engineering nowadays. Some scientists are beginning to study application of hybrid mated couple of ceramics and metals in the practice.The studies are focused on the combination of different kinds of material and on synthetic greases , lubricants and additives to improve the properties of the pairs. Because the materials of the pairs are different in their chemical composition , hardness , thermal conductivity etc. the wear volume and wear rate of the pairs show more discrepancy , which shortened the life of the pairs. To solve the problem the hybrid mated couple of material was tested. The results can be helpful for the wear-resisting and anti-corrosion machine parts used in special working conditions ( high temperature, high speed , heavy loads and corrosion ) such as bearings, valves and pistons etc.In this study , the two different kinds of metals ( the HIP-Si₃N₄/GCr15 is mainly concerned in this paper and the HIP-Si₃N₄/Mo50 is simply discussed considering it is selected as bearing materials in some foreign countries )and an engineering ceramics( HiP-Si3N4 ) were studied and analyzed in air , distilled water and different kinds of grease with additives in different load and velocity for the purpose of tribological applicatioa The results are as follows:1. Nonincrustation hot isostatic pressure method is first used for the test specimen of the HlP-Si^. The physical and dynamic performance parameters of the material were given .2. Quantitative wear analysis for engineering ceramics mated with steel under different lubrication was carried out with the help of precise analytical balance.3. The hybrid mated couple, HIP-SiaN/GCrlS and HIP-SiaNv^MoSO was tested in the dry, water and grease lubrication on the Timken wear tester , at the same time , HIP-Sijty/GCrlS was also studied on the Pin-on-disk wear tester. The micro-wear mechanism model of HlP-Si^ under dry friction was established , the calculation method of micro-plough and micro-cutting were discussed . The wear mechanism of water lubrication was also experimented and discussed , the results show that the frictional coefficient of HlP-Si^ can largely be decreased, but the wear volume is increased.4. The friction pairs of HIP-SijN/GCrlS was tested on Timken and Pin-on-disk wear tester lubricated with synthetic Lithium-base grease and MoSj Lithium base - grease of No. 18, 28 and 38 in different loads and velocities at five kinds of wear distances. The results show that the grease of No. 38 has the best anti-wear effect for the pairs of HIP-SiaN/GCrlS. When the sliding distance reaches a certain of value, the wear rate of both sides of the pairs is almost equal and constant.5. According to the characteristics of HIP-Si^yGCrlS pairs , physical and chemical property , cost of the additives , the wear-resistant effect of several kinds of extreme pressure additives on HIP-Si^/GCrlS pairs was tested...