Although both molybdenum disulfide grease and graphite grease are inclined to black grease in appearance, it is necessary to analyze the difference between these two grease products from their physical properties rather than judging from their appearance alone.
Molybdenum disulfide and graphite are used as high-temperature solid additives, but they are different.
Molybdenum disulfide grease
Molybdenum disulfide grease is composed of inorganic thickening agent thickening oil, and add molybdenum disulfide solid lubricant and anti-oxidation, anti-corrosion and other additives refined from molybdenum disulfide extreme pressure grease. This high temperature and high-pressure grease are designed for lubrication of bearings and motion devices under high temperature, high load/impact load, etc., providing long-term protection against wear and corrosion. Its applicable temperature range is – 30 ~ + 350 ℃.
The addition of molybdenum disulfide into the grease can improve the lubricating capacity of the grease, which can strengthen the grease film and act as extreme pressure additive when the grease film is subjected to short impact load or high heat. In addition, molybdenum disulfide can thicken grease, improve resistance to lose, enhance sealing and protection and improve high thermal stability.
Graphite grease is a kind of graphite grease made by thickening oil with the inorganic thickening agent and adding additives such as ultrafine graphite powder, anti-oxidation, and anti-corrosion. The ultrahigh temperature grease base oil will gradually evaporate at above 200 ℃, and graphite will be attached to the surface to form solid lubrication. It is specially designed for lubrication of high-temperature friction parts and bearings under heavy load/impact load or humid/polluted environment, providing maximum anti-rust and anti-corrosion protection. The applicable temperature range of the graphite grease is – 20 ~ + 450 ℃, and the highest intermittent heat resistance up to 500 ℃.
The biggest difference
It can be seen that the high-temperature resistance of graphite grease is obviously better than that of molybdenum disulfide grease, and the cost of graphite grease is lower than that of molybdenum disulfide grease. But why many manufacturers still choose to use molybdenum disulfide grease? The biggest difference between them is that although graphite grease is better than molybdenum disulfide grease in high-temperature resistance and low cost, the wear resistance and extreme pressure resistance of molybdenum disulfide are better than that of graphite grease. Therefore, it is better to use molybdenum disulfide grease when it is used in some harsh, heavy-duty gears and bearings, and parts with impact load.
Stanford Advanced Materials (SAM) is a trusted supplier of Molybdenum Disulfide (MoS2). We manufacture a wide variety of molybdenum products including pure molybdenum, molybdenum alloys, and molybdenum compounds.
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