Talk about aluminum rolling lubricant base
Houghton Company is a 150-year-old supplier of metal processing lubricants. We are involved in a very wide range of fields and have been outstanding in the field of aluminum rolling. Today, we hope to establish a communication platform with everyone here to initiate the project and repair it; ten steps to the grass, and everybody knows everything, to talk about all aspects of aluminum rolling, let us start with the basic part of it . Figure 1: Stribeck curve The three areas in the figure correspond to the three main lubrication conditions. In Zone I, the friction surfaces are separated by continuous lubricant oil. The thickness of the oil film is much greater than the sum of the roughness of the two surfaces. The frictional resistance is determined by the internal friction of the lubricant, which is determined by the viscosity of the lubricant. It can also be subdivided into fluid dynamic pressure lubrication or elastic fluid dynamic pressure lubrication conditions. The higher the oil viscosity, the faster the relative speed, the lower the load and the lower the surface roughness, the more likely it is that the power lubrication will occur. Many aromatic hydrocarbon-related substances are carcinogenic, and there are already many reports. Therefore, the choice of base oil is mainly based on the choice of cycloalkyl and paraffin base. Paraffin-based base oils have a high viscosity index and good stability. They are selected for most oil products, because they do not want too much viscosity change when the temperature changes, such as hydraulic oil, quenching oil and so on. Carcinogens, but there are different considerations on the base oil used as rolling oil. There are many rolling oil components, and the cycloalkyl base oil has good solubility and is beneficial to maintain the balance. Therefore, it is desirable to use a cycloalkyl base oil. More importantly, the temperature is increased, and the viscosity of the naphthenic oil is reduced more. In terms of rolling, biting difficulties can be reduced. However, paraffin-based base oils are also used, because in the power lubrication stage, the rolling pressure is so great that the rolls are elastically deformed, so they are actually in a state of elastic power lubrication, and the viscosity properties of paraffin bases are more suitable. Lubrication in this state. 3, boundary lubrication and boundary lubrication is achieved by polar molecules adsorbed on the surface to form a boundary lubrication film to achieve lubrication, the adsorption of the workpiece on the surface depends on the polarity of the molecule, the adsorption mechanism has physical adsorption, chemical adsorption and extreme pressure The hair should be as shown in Figure 2. The first is the physical adsorption, which mainly depends on the intermolecular force. It is a relatively long-range adsorption, and the power is the intermolecular force. The physical adsorption is related to the polarity of the molecule, but the adsorption molecule has not yet formed a chemical bond with the metal. Therefore, as shown in the figure 2 shows that the adsorption does not require activation energy, so it is easy to achieve, but the formation of physical adsorption, the energy is reduced slightly, indicating that the adsorption of the film is not high. If the temperature is higher, the adsorption may overcome the larger activation energy ΔEact2 as shown in FIG. 2 , and the chemical components in the lubricant react with the metal to form a lubricating film. The lubricating film comes from the molecules and metals of the lubricant. The joint action is an inorganic film with much lower energy, so the lubricating film has higher strength. The formation of the film is based on chemical reaction. Therefore, extreme pressure lubrication is also a controlled corrosion process. Figure 3 shows the physisorption, chemisorption, and chemical reactions formed during the lubrication process with S lubricant. It can be seen that the physical adsorption is polar adsorption, but no chemical bond (dotted line) is formed; chemical adsorption forms a chemical bond The chemical reaction is the formation of a layer of inorganic film that no longer has organic lubricant molecules in the film. 4, the characteristics of aluminum rolling lubrication Aluminum rolling lubrication, also follow the above lubrication mechanism. However, aluminum rolling lubrication has characteristics different from ferrous metal rolling. These characteristics of aluminum rolling lubrication need to be given full consideration in the formulation of rolling oil formulations. Stainless Steel Turnbuckle,Turnbuckle Types,Heavy Duty Turnbuckle,Small Turnbuckle Guangdong Gongyou Lift Slings Machinery CO.,LTD , https://www.wmpallettruck.com
Rolling is one of the more important means of aluminum processing. Modern aluminum alloy rolling materials include plate strips, wire rods, and pipe materials. There are thousands of different types of specifications, and they are continuously expanding. There are more than 3 meters in width and about 0.01 mm in thickness. . Good lubrication is required during rolling, especially for strip rolling, in order to reduce frictional power consumption, reduce roll wear and improve board surface quality. To achieve a good lubrication, first of all need to analyze the lubrication state, and then combine aluminum rolling characteristics to determine the means to achieve lubrication to achieve the purpose of lubrication.
1, Lubrication Status Figure 1 is the lubrication state curve proposed by Stribeck in 1900. 
As the pressure increases, the oil film becomes thin to the same order of magnitude as the surface roughness, and it enters the material boundary to lubricate, and the frictional surfaces are in contact with each other. The boundary layer formed by the polar molecules will be the friction pair (roll and roll The difference between panels and II and III is that in the II zone the frictional pair is still separated by the (organic) molecules of the lubricant, whereas in the III zone the secondary surfaces are very close to each other, the temperature is high and there is a group of lubricants. The inorganic film formed by the reaction with the metal separates the friction pair and is also called extreme pressure lubrication. For aluminum rolling lubrication, the lubrication is usually in the form of a dynamic lubrication and boundary lubrication of the mixed lubrication body, the friction coefficient between 0.03-0.10, the film thickness is between 0.1-1.0 microns.
2. Power lubrication to achieve the above mentioned in the I area of ​​the power lubrication is mainly dependent on the viscosity of the lubricating oil. The viscosity of lubricating oil is mainly related to the base oil, so power lubrication depends to a large extent on the base oil. Base oils are generally classified into paraffinic, cycloalkyl, and aromatic groups, and their performance is shown in Table 1. 
In the so-called three old oil refining technologies (solvent dewaxing, solvent refining, and white clay supplementation), cycloalkyl groups are related to paraffin-based oil sources, and the widely used hydrogenation oil refining technologies have now become independent of the quality of oil sources. As a result, the quality of the base oil has been significantly improved. As shown in Table 2, the quality of the hydrotreated base oil has been significantly improved. For the base oil of the rolling oil, the hydrorefined base oil should be preferred. 
If the adsorption forms a chemical bond with the matrix metal, then chemical adsorption occurs. As shown in FIG. 2, the chemisorption needs to overcome the activation energy ΔEact1, and the activation energy value is not so large, so it can be performed at a suitable temperature. After chemical adsorption, there is a greater reduction in energy, and the adsorption membrane is relatively strong. Most domestic materials claim that the lubricant is an anti-wear agent or an oil agent. 
(1) Aluminum is a face-centered cubic metal, four 111 close-packed surfaces, three sliding directions in 110, a total of 3x4 = 12 slip systems, easily deformed and sticky aluminum; aluminum is amphoteric metal, strong reactivity, and Acids and bases can react; aluminum is low strength, foreign impurities easily pressed into the surface. Combining these factors, the surface of aluminum is prone to defects during the rolling process, so the surface quality will become one of the more important goals of aluminum rolling lubrication.
(2) During the rolling process, because of the friction, especially the aluminum powder produced in the front slide area, aluminum is not magnetic and is difficult to remove by magnetic filtration. However, the aluminum powder must be removed in time. Otherwise, the aluminum powder may be pressed back. surface. Therefore, how to effectively remove the aluminum powder produced during the rolling process will be a key technology in rolling lubrication.
(3) S is a very effective lubricant material. Sulfide is more polar and forms physical adsorption and chemical adsorption on the surface, which acts as an oil or anti-wear agent. When the local temperature is high, it reacts with iron to form an FeS inorganic lubricating film with a layered structure, which acts as an extreme pressure lubricant. However, due to the sulphur-aluminum reaction, lubricity components containing S are generally not used in aluminum rolling lubrication and can only be used in turn, such as phosphates. Phosphate adsorption mechanism is generally believed to be formed by nucleophilic addition as shown in Figure 4, or by acid-base reaction, as shown in Figure 5. 
(Houghton Company Chen Chunhuai March 22, 2016)