Organic chemical wear status of zirconia ceramic cylinder liner
The corrosion and wear of zirconia ceramic cylinder liners occur at low or high operating temperatures. Chemical corrosion is caused by the formation of substances in the air (gases, internal moisture, O2) or the oxidation of lubricating grease by air (the production of organic compounds). Most of the products are converted into corrosive substances when ignited.
The effect of corrosion and wear inside zirconia ceramic cylinder liners can be divided into two steps:
1) Quickly generate a continuous protective film on the surface. The protective film can be hydroxide, organic salt, sulfate or fluoride.
2) The wear of the protective film exposes the surface layer again, causing it to suffer from corrosion again.
In most cases, the thickness of the membrane determines the wear characteristics. Usually, corrosion transforms into a film that is harder than the surface, and the film thickness reaches a critical value of thinness. The film will be transformed into a protective film again by the industry. Little do they know, sometimes the tensile strength of corrosion converted into a film is low (metal materials such as fluorides, sulfates, and phosphides). This type of film has a lower wear value as an excellent boundary lubricant. At this point, the conversion of thicker corrosion into a film will reduce the probability of contact between metal materials and the corresponding adhesive wear. By comparison, this type of corrosion transforms into a film that initially damages and promotes corrosion wear. Therefore, there is a selection problem between corrosion wear and adhesive wear.
When the sweep temperature is low (humid and cold atmosphere), corrosion wear may also be exacerbated by excessive condensation water entering the zirconia ceramic cylinder liner. The water inside the zirconia ceramic cylinder liner is likely to wash away the floating oil on the inner wall of the cylinder, or together with hydrochloric acid derived from natural materials, promote the formation of corrosion spots. When the moisture content is low, the harm is not significant, while when the moisture content is too high, the ignition rate slows down and decreases. As a result, these natural particles still ignite at the surface of the zirconia ceramic cylinder liner, causing an increase in cylinder wall temperature and posing a sub hazard to the lubrication effect. This will cause the combustion to become mechanized, promoting the conversion of hard precipitates and increasing wear.
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