The improvement of sustainable economic benefits, the improvement of machining quality, and the improvement of production efficiency largely depend on the selection of the correct metalworking fluid. The physical and chemical properties of the processed materials are different, and new problems such as the difficulty of cutting and the compatibility with the cutting fluid will be reflected in the cutting operation. For the difficult-to-machine materials and their compatibility with cutting fluids, the seniors who operate on-site are specially summarized as follows:
Aluminum: Soft, easy to stick cutting tools. If the emulsion is highly alkaline, it will react chemically with aluminum, resulting in layering of the emulsion. Special emulsion or paraffin-based mineral oil should be used as cooling lubricant.
Brass: A lot of fine chips are generated when cutting, which is easy to turn the emulsified oil green. Oils containing active sulfur can discolor processing materials, such as oil separators, filter equipment is required.
Bronze: Significant plastic deformation occurs before shearing, which can turn the emulsion green. If the oil is selected, there must be a filter device.
Copper: sticky and tough, fine curled chips are produced during cutting, which can make the emulsion turn green, affect the stability of the emulsion, and cause stains under the action of active sulfur. If the oil is selected, it should be equipped with filtering equipment.
Malleable Iron: A large amount of fine chemically active abrasive chips are produced when cutting. These active fines are like a filter medium, which weakens the activity of the emulsion, and can generate iron soap, which turns the emulsion into reddish brown and deteriorates the stability of the emulsion. If oil is used, iron filings must be removed with a centrifuge or filter.
Lead and its alloys: easy to cut, can generate lead soap, destabilize the emulsion. If oil is used, it has a tendency to thicken, and it is necessary to prevent the use of oil containing a large amount of fat.
Magnesium: produces fine chips during cutting, which is flammable. Generally, water-based cutting fluid is not used, and low-viscosity oil can be used as cutting fluid.
Nickel and high-nickel alloys: High heat is locally generated during cutting, and the chips may sinter. Heavy-duty emulsions or non-reactive sulfurized oils are available.
Titanium: produces abrasive, combustible chips, prone to work hardening, apply heavy-duty emulsified oil or extreme pressure oil.
Zinc: The cutting surface is irregular, and it is difficult to obtain a good finish. It forms zinc soap with the emulsion to separate the emulsion. Special emulsion should be selected.
