Oil Additives Based on Molybdenum Disulfide

Molybdenum disulfide is one of the most effective anti-wear and anti-friction additives in lubricants. Its unique layered structure allows it to function as a solid lubricant, significantly reducing friction between surfaces. Unlike conventional lubricants, MoS2 is used in high-temperature and high-pressure conditions. This material, with its high chemical stability and resistance to oxidation, prevents corrosion in corrosive environments.

Suitable for:

Military, aerospace, and mining industries that require performance under high-temperature and high-pressure conditions.
Special oils for bearings, gearboxes, and heavy machinery operating in harsh environmental conditions.

Pin On Disk Wear Test

In the Pin on Disk Wear test, the coefficient of friction is examined. For this purpose, two samples were tested according to ASTM G99 standards: a base oil and a base oil mixed with 0.4% Wt MoS2 additive.

The test was conducted at a temperature of 100 ºC according to ASTM G99 standards. The applied force was 200 Newtons, the sliding distance was 1000 meters, and the motor speed was 250 rpm.

In this test, it was observed that the coefficient of friction for the base oil mixture with 0.4 % Wt by weight of MoS2 was lower than that of the base oil. This reduction in the coefficient of friction shows that the MoS2 nanoparticles have helped improve the lubrication properties of the oil.

It appears that these nanoparticles, due to their layered structure, easily slide over one another. This property improves the lubrication properties of the oil and provides a more uniform and effective distribution of the oil on moving surfaces. MoS2 nanoparticles have high thermal stability which allows these particles to maintain their lubricating performance at higher temperatures. As a result, even at 100 ºC, these nanoparticles can help reduce friction.

 

Images of the four-ball test: The test was conducted with an applied force of 392 Newtons, over a time of 3600 seconds, with a motor speed of 1200 rpm.

Wear Test (Four-ball Test)

The four-ball test or wear test is another test that can determine the effect of various additives in oil on the amount of wear. Below are the images of this test to compare the wear level when using base oil and base oil mixed with MoS2 based additive.

In the four-ball test, images (a) and (b) represent the base oil without the MoS2 additive. They show wear track lengths of 1581.73 μm and 1682.29 μm, respectively. Images (c) and (d) correspond to the base oil containing the MoS2 additive, which wear track lengths of 707.04 μm and 738.69 μm, respectively.

In general, these images show that when using base oil, the surfaces are exposed to direct wear, and the effects of wear are clearly visible. The wear tracks are long and extensive. This shows a greater damaged surface. But when MoS2 nanoparticle-based additives are added to the base oil, they effectively reduce length of the wear track.These findings suggest that MoS2 nanoparticles can be used as an effective additive in lubricants and improve the mechanical performance of lubrication systems. Based on these results, it can be concluded that using MoS2 nanoparticles in lubricants can significantly extend the service life of mechanical components and equipment while reducing maintenance and repair costs.

Table: Oil Additive Based on Molybdenum Disulfide (MoS2)