Composition sozh do it yourself aluminum cutting. Dry and semi-dry machining. Features of the use of cutting fluids

The aluminum drawing process involves metal pressure treatment, during which a workpiece with a diameter of 7-19 mm is pulled through a hole of a smaller diameter. Production involves the use of cutting fluids (coolants) of a certain type.

For wire rod with a cross section of 7.2 mm to 1.8 mm, the processing takes place on multiple equipment without slipping. In this case, aluminum is used, which has a high density.

With thinner drawing (0.59-0.47 mm), aluminum is processed on sliding machines. The speed of the workpiece passing through the equipment is 18 m/s. In this case, a wire drawing lubricant is used in the form of an emulsion.

The choice of lubricants also depends on the type of processing equipment. If a technician applies coolant by spraying during operation, the pump volume must be taken into account. Recently, low-viscosity materials have been more frequently used for aluminum forming.

Since aluminum forming produces a high concentration of attrition particles, drawing lubricants must have a low viscosity. This will extend the life of the coolant and increase the economics of the process.

Moreover, an increase in viscosity is observed with an increase in the fineness of processing. Rougher aluminum drawing processes require thicker oils, while liquid lubricants are used for finer operations.

Aluminum drawing, the coolant for which has a set of required characteristics, should be created on the basis of mineral oils or synthetic substances. This will maximize the protection of the surfaces of mechanisms and processed materials from wear and corrosion.

The drawing of aluminum wire with annealing puts forward increased requirements for lubricants in terms of its temperature characteristics. In carrying out such a process, deposits should not remain on the surface of the material.

A well-known worldwide manufacturer of high quality cutting fluids is the German brand Zeller Gmelin. This company has developed a range of products to help optimize the aluminum drawing process.

Sale of cutting fluids directly from the manufacturer

The highest quality coolants for this type of metalworking are available under the name Multidraw AL, Multidraw ALM, Multidraw ALF, Multidraw ALG. Each product meets certain conditions for the drawing process.

The company LLC "" has the right to sell these coolants in Russia. All products have the appropriate quality certificates and have passed a number of laboratory tests. The manufacturer's reputation is impeccable. This guarantees the quality of lubricants, which are sold at the best prices.

We offer our clients a full range of services. You can buy the optimal type of lubricants by contacting our competent specialists. After listening to your conditions of metal forming, our experienced staff will select the required type of product. This will minimize production costs and increase the competitiveness of finished products.

Realization is carried out wholesale and retail. Delivery is carried out in the shortest possible time to almost every city in our country. The presence of products in our own warehouse allows you to send the order very quickly. There is a possibility of self-delivery of products from a warehouse in Podolsk.

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Most machine tool operators find it difficult to imagine a machining process without the use of a cutting fluid (coolant). However, in some cases, there is a need for dry processing, which may be due to the lack of appropriate equipment preparation, or other conditions for the work. Analytical data from various sources indicate that the cost of providing workpiece cooling is 2-3 times higher than the cost of cutting tools. In addition, the world community is increasingly concerned about the protection of health and the environment during production work. Disposal of used cutting fluid is a major concern for most businesses, and inhalation of its fumes can cause significant harm to human health. Due to the high costs of coolant disposal, European manufacturing plants are increasingly using dry or semi-dry (with minimal coolant) machining technologies, in contrast to US factories. However, countries such as Germany still have to reckon with the current economic and production conditions and use coolant. However, new regulations have already been proposed that limit the use of coolant in machining.

Let's talk more about dry machining. Can materials be machined without coolant? In most cases it is possible, but this issue requires more detailed consideration.

First, the cutting fluid performs a number of tasks:

Cooling. That is why the liquid is called coolant.
Grease. Tough materials such as aluminium, build up on the cutting edge, so it is necessary to reduce friction and, consequently, their heating.
Chip cleaning. In many cases, this task is the most important. If chips hit the surface being machined, it will damage the surface and cause a much faster tool blunting. In the worst case, a cutter or cutter inserted into a slot or hole can become clogged with chips, causing them to overheat or even be damaged.

In dry machining, each of the above functions of the cutting fluid must be taken into account.

Lubrication and build-up on the cutting edge

Let's talk about lubrication. I paid the least attention to this topic, but this does not mean that lubrication is not important in processing. First of all, lubrication contributes to the more efficient operation of the cutting tool with less heat. When the front edge of the cutter slides over the workpiece, it heats up due to friction. In addition, the chips also rub against the cutter, generating additional heat. Lubrication reduces friction and therefore heat. Thus, one of the functions of lubrication is to improve cooling efficiency by reducing heat generation. The main function of the lubricant is to prevent build-up on the cutting edge. Anyone who has seen how aluminum sticks to a cutter immediately understands the importance of this issue. Built-up edges can cause damage to the tool very quickly and thus delay work.

Fortunately, the presence or absence of build-ups mainly depends on the type of material being processed. Most often, build-up occurs when machining aluminum and steel with a low content of carbon or other alloying elements. In this case, you need to use very sharp cutters with large rake angles (positive rake angle is your friend!). Also, spraying a small amount of coolant helps to cope with this problem, and the efficiency of this method is not inferior to the traditional method. Most importantly, do not forget to take these measures before the formation of adhesions between the chips and the surface being machined.

Chip cleaning

The next problem with dry machining is chip removal. Compressed air can be used for this purpose. However, this cleaning method may not be fully effective in some operations, such as drilling. Deep boring and drilling are two of the most problematic dry machining operations in terms of chip removal. To solve the problem, you can use process air supplied to the tool, but spraying a small amount of coolant is a better solution. Liquid coolant is better at this task, because it has a higher density, better transfers chips and cools the machined surface. But the correct application of spraying allows you to extend the life of the tool compared to the traditional method described above. It should be noted that natural chip removal is more effective on horizontal milling and turning machines than on vertical ones, especially in dry or semi-dry machining, due to the presence of gravity.

Cooling

Let's talk about cooling. Temperature is the most important factor affecting the life of a cutting tool. A slight heat softens the material, which has a positive effect on the processing. At the same time, strong heating softens the cutting tool and leads to its premature wear. The permissible temperature depends on the material and coating of the cutting tool. In particular, carbide withstands significantly higher temperatures than high speed steel. Some coatings, such as TiAlN (titanium aluminum nitride), require high operating temperatures, so these tools are used dry. There are many examples where cutting out coolant while maintaining technology results in longer tool life. Carbide tools are susceptible to the formation of microcracks in the event of sudden temperature changes during uneven heating and cooling. Sandvik recommends in its educational course not to use coolant, at least in large quantities, in order to prevent the formation of microcracks. It should also be noted that high heat adversely affects the accuracy of processing, since as a result of heating, the size of the workpiece changes.

How can workpieces be cooled without coolant? First, let's look at the most common cooling methods. There are two types of coolants - water-based coolants and coolants based on oil. Water-based coolants are most effective for cooling. How much? Comparative data are shown in the following table:

coolant	Specific heat	Steel A (hardened) Decrease in temperature, %	Steel B (annealed) Decrease in temperature, %
Air	0.25
Oil with additives (low viscosity)	0.489	3.9	4.7
Oil with additives (high viscosity)	0.556	6	6
Aqueous moisturizer solution	0.872	14.8	8.4
Water-soda solution, 4%	0.923	-	13
Water	1.00	19	15

First, the data presented in the table indicate that the efficiency of various types of coolants directly depends on their specific heat capacity. Secondly, it should be noted that air is the worst refrigerant - its characteristics are 4 times inferior to those of water. Also interesting is the fact that oil coolants are almost 2 times inferior to water in terms of cooling properties. Given this fact, as well as safety issues, it is not surprising that many enterprises use water-based coolants - they are the best coolants. However, water-based coolants only work effectively up to a certain cutting speed, and the higher the speed becomes, the worse they cool the material and tool. One of the reasons for this phenomenon is that at a high cutting speed, the coolant does not have time to penetrate into all the recesses and cracks in the material. As a result, the cooling becomes less and less qualitative, resulting in a decrease in the cooling efficiency of the carbide tool at a cutting speed exceeding a certain value.

Heat-resistant coatings such as TiAlN that do not require cooling can be used, but it is possible to do without them. For example, compressed air can be used for cooling, but it must be remembered that large volumes of air will be required to achieve efficiency comparable to water cooling. In cases where cooling is required, it is much more efficient to use humidified air containing atomized liquid. Spraying also provides lubrication, which can be useful for materials such as aluminium. In addition, at high cutting speeds, humidified air penetrates into all cavities in the material better than water with water cooling.

Another method of cooling is the use of chilled air. There are many ways to cool the air, and it naturally cools as it exits the nozzle, but a more efficient solution is to use a device called a vortex tube. For the above data on different types of coolants, as well as detailed information on research related to the use of air and vortex tubes for cooling, you can find in Brian Boswell's scientific paper "The use of air cooling and its effectiveness in dry processing of materials."

This work can be very useful if you want to understand the details. Boswell is considering equipping some lathe chucks with air channels, but concludes that the most effective option is to use vortex tubes. If you are going to use only air, it must be directed to the right places to ensure effective cooling. Boswell found that adjusting the vortex tube was much easier because the nozzle could be further away from the material being processed. At the same time, this device is able to cool the material as efficiently as a traditional water cooling system.

Parameters of dry machining of materials

Let's assume that you don't have accessories like a vortex tube, but you use dry or humidified compressed air for lubrication and chip removal. How does this affect the machining conditions (feed and cutting speed) compared to conventional wet machining?

Consider separately such a parameter as feed per tooth. The adjustable value, depending on the type of cooling, is the cutting speed. In this case, the feed rate for a given feed per tooth will decrease slightly.
If a certain cutting speed threshold is exceeded, the adjustment depending on the type of cooling does not work. In most cases, the cooling system will be turned off altogether. Let's call this threshold value the critical cutting speed. This speed will be slightly slower, but it can definitely be accepted as the recommended speed for TiAlN-coated tools. TiN (titanium nitride) coated tools will still run more efficiently at these speeds with cooling, so the critical cutting speed is somewhere between the speeds recommended for TiN and TiAlN coated tools. Obviously, the critical speed will depend on the type of material being processed, so there is no universal value for all cases.
For cutting speeds below critical, a special correction factor is applied. Like the critical speed, the coefficient depends on the material being processed and takes values from 60% to 85%. In other words, for some materials a factor of 60% of the recommended speed is used (tool manufacturers' recommendations are based on the wet machining method), while for other materials the factor can be as high as 85%. The coefficient depends on the thermal conductivity of the material (heat-resistant alloys are quite difficult to process, since they conduct heat poorly, and a large amount of build-up is formed during cutting), the lubricating properties of the coolant, etc.

What about the quality of the surface treatment?

This is the last question regarding dry machining. Often, the quality of the dry finish is lower than with wet machining. There are many factors that affect quality, but in most cases it all comes down to a decrease in cutting speed. To maintain the quality of processing, it is important to compensate for the decrease in speed by using a tool with a larger radius (for example, a milling cutter). A secondary factor is lubrication, which reduces wear and ensures smooth cutting. In this case, humidified air will help you.

Results

So what are the conclusions?

It is clear that machining with the use of a cutting fluid is superior in parameters to dry or semi-dry machining, if you do not take into account the cost of coolant and have the appropriate equipment available. However, the effects are not as pronounced as it might seem. Humidified air can be used to process viscous materials, and vortex tubes and other air cooling devices are no less effective than the traditional wet method. In this case, you will at least have a stream of compressed air to clean the workpiece from chips. It should be understood that dry machining leads to a change in cutting speed by 20-25%. Feed per tooth depends on the implementation of water cooling. Proper coolant nozzle orientation can increase feed per tooth by 5%, and high-pressure coolant through the spindle allows for even greater productivity gains.

In some cases, the refusal to use coolant is quite a challenge:

Heat resistant alloys and titanium should be machined with wet cutting, except when using tools where dry machining is recommended. The above materials have insufficient thermal conductivity to be used solely for air cooling.
Materials that build up on the cutting edge (some stainless alloys and aluminium) require coolant or at least humidified air to provide lubrication.
Without coolant, it is very difficult to remove chips from deep holes. This problem can be solved by supplying humidified air under pressure.

Remember!

If your spindle is not the fastest in the world, you will most likely have to reduce your cutting speed due to insufficient RPM. This is especially true when machining aluminum (or other soft materials such as brass), as well as when using small carbide cutters. However, in this case, the rejection of traditional liquid cooling is not critical.
It is often possible to increase the feed rate by reducing the chip thickness.

Anyone, even a novice metalworking specialist, knows that when performing turning work on a machine, it is imperative to use cutting fluids (coolants). The use of such technical fluids (their composition may vary) allows you to solve several important problems at the same time:

cooling of the cutter, which is actively heated during processing (respectively, extending its service life);
improving the surface finish of the workpiece;
increasing the productivity of the metal cutting process.

Types of coolant used in turning

All types of coolant used for turning work on the machine are divided into two large categories.

Water based coolant
Oil-based coolant

Such liquids remove heat from the processing area much worse, but provide excellent lubrication of the surfaces of the workpiece and tool.

Among the most common coolants that are used when, the following can be noted.

A solution of soda ash (1.5%) in boiled water. Such a liquid is used when performing rough turning on a lathe.
An aqueous solution containing 0.8% soda and 0.25% sodium nitrite, which increases the anti-corrosion properties of the coolant. It is also used for rough turning on the machine.
A solution consisting of boiled water and trisodium phosphate (1.5%), almost identical in its cooling effect to liquids containing soda ash.
An aqueous solution containing trisodium phosphate (0.8%) and sodium nitrite (0.25%). It has improved anti-corrosion properties and is also used in rough turning on lathes.
A solution based on boiled water, containing in its composition a special potassium soap (0.5–1%), soda ash or trisodium phosphate (0.5–0.75%), sodium nitrite (0.25%).

Water-based solution containing 4% potassium soap and 1.5% soda ash. Coolants, which contain soap, are used when performing roughing, as well as shaped turning on a lathe. Potassium soap, if necessary, can be replaced by any other soap that does not contain chloride compounds.
A solution based on water, to which emulsol E-2 (2–3%) and technical soda ash (1.5%) are added. Coolant of this type is used when, for the cleanliness of the machined surface of which there are no high requirements. With the use of such an emulsion, workpieces can be machined at high speeds.
An aqueous solution containing 5–8% emulsol E-2 (B) and 0.2% soda or trisodium phosphate. With the use of such a coolant, fine turning is performed on a lathe.
An aqueous solution containing emulsol based on oxidized petrolatum (5%), soda (0.3%) and sodium nitrite (0.2%). You can use such an emulsion when performing roughing, as well as finishing turning on the machine, it allows you to obtain surfaces of higher purity.
An oil-based fluid containing 70% industrial oil 20, 15% 2nd grade linseed oil, 15% kerosene. Coolant of this composition is used in cases where high-precision threads are cut and workpieces are processed with expensive shaped cutters.

Sulfofrezol is an oily cutting fluid activated with sulfur. This coolant is used when turning with a small cut section. When performing rough work, characterized by active and significant heating of the tool and workpiece, the use of such coolant can be harmful to the machine operator, as it emits volatile sulfur compounds.
A solution consisting of 90% sulfofresol and 10% kerosene. Such a liquid is used for threading, as well as for deep drilling and finishing workpieces.
Pure kerosene - is used when it is necessary to process workpieces made of aluminum and its alloys on a lathe, as well as when finishing using oscillating abrasive bars.

Features of the use of cutting fluids

For the use of coolant to be effective, a few simple rules should be considered. The flow rate of such a liquid (regardless of whether it is an emulsion or an aqueous solution) should be at least 10–15 l / min.

It is very important to direct the coolant flow to the place where the maximum amount of heat is generated. Such a place when performing turning is the area where the chips are separated from the workpiece.

From the very first moment when turning on the machine, the cutting tool begins to heat up actively, so coolant should be applied immediately, and not after some time. Otherwise, with a sharp cooling of a very heated one, cracks may form in it.

More recently, an advanced cooling method has been introduced, which involves the supply of a thin stream of coolant from the back of the cutter. This method of cooling demonstrates particular efficiency when, on a lathe, a tool made of high-speed alloys is required to process a workpiece made of hard-to-cut materials.

To this end, Quaker Chemical Corp. conducted a series of tests on the face machining of aluminum blanks to evaluate the effects of various coolants on cutting power and tool wear. When machining with a new cutting tool, the coolant had no effect on the machining forces generated at the same cutting speed. However, the more the tool machined the workpiece, the greater the difference in power needed to effectively machine with different coolants.

These results show the following

The effect of metallic fluid on cutting power is minimal with newer cutting tools. Thus, the difference between the effect of two different coolants on cutting power may not be noticeable until the cutting edges of the tool begin to wear.

The increase in power when milling aluminum is a direct result of cutting edge wear. The rate of this wear is directly affected by both the cutting speed and the fluid used in metal processing.
The relationships between these variables are linear (cutting speed, cutting edge wear and cutting power all increase together). Armed with this knowledge, fabricators can potentially predict the condition of the cutting edge at any point in the milling process, as well as the power needed at other, untested cutting speeds.

Entering the lab

Testing focused mainly on two types of coolants: microemulsions and macroemulsions, each of which was diluted at a concentration of 5% in water. The main difference between the two is the size of the suspended oil droplets. The macroemulsion contains particles with a diameter of more than 0.4 microns, which give an opaque white appearance to the coolant. The microemulsion has a smaller particle diameter and has a translucent appearance.

The experiment was performed on a Bridgeport GX-710 three-axis CNC machine. The blank was a block of 203.2 by 228.6 mm by 38.1 mm 319-T6 aluminum alloy, cast, containing copper (Cu), magnesium (Mg), zinc (Zn), and silicon (Si). Machining was carried out with a face mill with a diameter of 18 mm with eight inserts with a 15-degree rake angle and radial radii of 1.2 mm. It machined with an axial depth of 2mm and a radial depth of 50.8mm. Each coolant formulation was applied to the cutting zone for 28 milling transitions at two different cutting speeds, 6,096 rpm (1460 m/min) and 8128 rpm (1.946 m/min), to remove 1,321.6 material cm3. Feed rates at both speeds were 0.5 mm per revolution (0.0625 mm per insert per revolution).

Speed, wear and power

The power measurements for this study during processing were obtained using an instrumental control system and adaptive control. The test results are shown in the charts in this article. As expected, higher cutting speeds resulted in higher machining speeds. However, as described above, the differences in cutting power between the two fluids were minimal with the new cutters.

At the start of the process, workpiece material properties and cutting edge geometry are the dominant factors influencing cutting power. Differences between the working characteristics of the metal medium appeared only after the geometry of the cutting edge changed during wear. The choice of metalworking fluid directly affected the rate at which this wear occurred and, accordingly, the required cutting power at any given point in the milling operation.

Assuming a certain baseline performance level for the two fluids being compared, testing should be performed until the inserts begin to wear to determine which fluid allows higher cutting speeds to be maintained for a longer period of time.

The constructed graphs made it possible to say that the rate of increase in power can be used to predict the state of the insert at any given point in the milling operation. Likewise, power measurements made at multiple cutting speeds can be used to obtain the required power at other, unverified cutting speeds.

Proof

While the x-axis in Figure 1 consists of the raw material removal volume data, Figure 2 uses the natural logarithm of this variable. Plotting the volume of material removed in this way results in a slope, which is the exact rate at which power increases with subsequent processing. This measurable measure is needed to predict tool wear and cutting performance at various cutting speeds. However, these data only show that cutting power and material removal increase together. Confirmation of insert wear is especially important because the power increase driving force requires additional testing (in particular, to correlate the line slopes in Figure 2 directly with insert wear that occurs during machining).

These tests added two additional coolants: one more macroemulsion and one more microemulsion. Each of the four fluids was applied at a cutting speed of 1.946 m/min. until 660 cm3 of material has been removed. This provided sufficient time for abrasion and, in some cases, metallic adhesion to occur. We then measured the wear of the flanges for four fluids in relation to the parameter that relates the cutting power to the volume of the metal slot (in particular, the slope of the power compared to the natural volume of metal removed). As shown in Figure 3, this confirmed the linear relationship between insert wear and increased cutting power during machining.

Other Findings

Although test results cannot necessarily be extrapolated beyond aluminum milling, research shows that microemulsion works best if the goal is to machine at the highest possible speed. This is because a denser microemulsion with smaller diameter oil droplets tends to remove heat more efficiently than a macroemulsion and its relatively large droplets. However, operations involving slower cutting speeds may contribute to the macroemulsion and its comparatively greater lubricity.

Whatever the part, the best way to find the right coolant is to try different formulations in action. Understanding the relationship between cutting speed, tool wear, and cutting power, and how cutting fluids can affect these factors, is critical to making the right choice.

The following requirements apply to the metalworking process of aluminum alloys:

1) high processing precision and low roughness;

2) high productivity and exclusion of finishing work;

3) low sensitivity to the spread of mechanical properties and geometric dimensions (a variety of tool material grades);

4) relatively low cost of the tool.

However, the processing of these materials causes significant difficulties associated with their high viscosity, which leads to the formation of build-up, overheating and a decrease in the durability of the cutting tool, and a decrease in the quality of the machined part.

The use of modern machine tools, tools with wear-resistant coatings and the supply of cutting fluids (coolant) to the cutting zone does not always provide the required quality and productivity parameters. Nevertheless, today metal-cutting machines meet the requirements of accuracy. The offered range of tools and the results of numerous studies allow you to choose such cutting inserts, the use of which maximizes productivity and quality of processing.

At the same time, despite the development of a large number of coolant grades and tests in this area, there is no single methodology that ensures the choice of the most effective coolant. The selection of an efficient coolant brand, according to available data, can reduce cutting forces by 20%. Therefore, it is advisable to develop a methodology that ensures the choice of such a brand.

In general, coolants have lubricating, cooling, washing, dispersing, cutting, plasticizing and other effects on the cutting process. One of the main functional actions of the coolant is the lubricating effect, since the reduction of friction in the cutting zone leads to a decrease in the intensity of tool wear, to a decrease in cutting forces, average cutting temperature, and roughness of the workpiece. Therefore, it is necessary to investigate the lubricating action of the coolant in order to select a specific grade for processing these alloys.

Study of the lubricating effect of coolant

The lubricating effect is evaluated according to the test results both on the metal-cutting machines themselves in the process of processing, and on friction machines. The use of friction machines allows not only to reduce the consumption of materials, the coolant itself and the time spent, but also to eliminate the influence of other actions. Therefore, the lubricating effect of the coolant in this work was evaluated based on the results of tests on a friction machine. On fig. 1 shows the friction machine used for coolant research.

Since turning is the most common type of machining, such a loading scheme for a friction machine was used for research, which made it possible to simulate this type of machining, the “block-roller” scheme (Fig. 2).

The block is made of the material of the processing tool - T15K6 hard alloy. As a material for the manufacture of rollers, one of the most common representatives of aluminum alloys, D16 alloy, was chosen.

The research was carried out at a pressure force on the shoe P=400 N and a roller speed of n=500 rpm. The loading force is chosen in accordance with the cutting forces that arise during the metal processing of these alloys. The speed of the roller is obtained by calculation from its diameter and cutting speed recommendations.

The roller was mounted on the shaft and brought into contact with the shoe. The chamber was closed with a lid and filled with the tested coolant. Then the rotation of the roller was switched on with a frequency n, and by means of the loading mechanism, the load on the pad was smoothly applied until it reached its value R.

According to the readings of the instruments, the maximum and minimum values of the friction moment were determined. The average value of the moment was obtained as the arithmetic mean of the results of five experiments. Based on the available data, the actual coefficient of friction was calculated f according to the formula:

For testing, 10% aqueous coolant solutions of several brands were used: Addinol WH430, Blasocut 4000, Sinertek ML, Ukrinol-1M, Rosoil-500, Akvol-6, Ekol-B2. In addition, the tests were carried out without the use of coolant.

The research results are given in table. one.

The results of the studies carried out make it possible to evaluate the lubricating effect of the tested coolants during the processing of the presented groups of materials. The data obtained provide the possibility of selecting the most technologically effective coolant for processing the given materials in terms of lubricating effect.

The effectiveness of each grade of coolant must be determined in comparison with the treatment without the use of coolant. The value of efficiency K cm for lubricating action when processing various materials is determined by the formula:

The lower the K cm value, the more effective this grade is in processing the tested material. In table. 2 shows the effectiveness of the tested coolant grades in terms of lubricating action.

It is known that when machining at low speeds, when the coolant is best in the cutting zone, the lubricating effect of the coolant has the greatest effect. Thus, the use of coolant with a high lubricating effect is advisable for roughing.

According to the table Table 2 shows that when processing aluminum alloy D16, the most effective lubricating fluids are Rosoil-500 (K cm = 0.089), Akvol-6 (K cm = 0.089) and Ekol-B2 (K cm = 0.096).

conclusions

1. In the work, experimental studies of the lubricating action of the tested coolants were carried out. The presented results make it possible to choose the most effective brand of coolant for rough machining of aluminum alloys.

2. The results of the work will be especially useful in the production of aircraft parts, as aviation parts are subject to increased requirements for quality and processing accuracy.

3. The use of effective coolant provides the maximum possible reduction in friction and average cutting temperature, which leads to an extension of tool life, a decrease in cutting forces, a decrease in surface roughness, and an increase in machining accuracy.

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