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Cutting tool materials can be divided into two main categories: stable and unstable.
Unstable materials are “substances that start at a relatively low hardness point and are then heat treated to promote the growth of hard particles inside the original matrix, which increases the overall hardness of the material at the expense of some its original toughness. Since heat is the mechanism to alter the structure of the substance, and at the same time the cutting action produces a lot of heat, such substances are inherently unstable under machining conditions”.
Stable materials on the other hand are “substances that remain relatively stable under the heat produced by most machining conditions, as they don't attain their hardness through heat. They wear down due to abrasion, but generally don't change their properties much during use” .
Most stable materials tend to be hard and very fragile and are generally used for large, heavy and stiff machinery.
Unstable materials tend to be softer and thus tougher and are generally used in hand tools and light machinery.
The main materials used for cutting tools …show more content…
They are composed of a base mineral or petroleum oil and often contain polar lubricants such as fats, vegetable oils and esters as well as extreme pressure additives such as Chlorine, Sulphur and Phosphorus. Straight oils provide the best lubrication and the poorest cooling characteristics among cutting fluids.
Synthetic Fluids
They contain no petroleum or mineral oil base and instead are formulated from alkaline inorganic and organic compounds along with additives for corrosion inhibition. They are generally used in a diluted form (usual concentration 3 to 10%). Synthetic fluids often provide the best cooling performance among all cutting fluids.
Soluble Oil Fluids
They form an emulsion when mixed with water. The concentrate consists of a base mineral oil and emulsifiers to help produce a stable emulsion. They are used in a diluted form (usual concentration 3 to 10%) and provide good lubrication and heat transfer performance. They are widely used in industry and are the least expensive among all cutting fluids.
Semi-synthetic Fluids
They are essentially a combination of synthetic and soluble oil fluids and have characteristics common to both types. The cost and heat transfer performance of semi-synthetic fluids lies between those of synthetic and soluble oil …show more content…
In this application pressurized liquid CO2 is allowed to expand and following the ideal gas law, this is accompanied by a drop in temperature, enough to cause a change of phase into a solid. These solid crystals are redirected into the cut zone by either external nozzles or through-the-spindle delivery, to provide temperature controlled cooling of the cutting tool and work piece. Existing CNC machines can be retrofitted with this safe and environmentally coolant approach. In applications such as turning, milling or drilling tool life and throughput have been improved substantially, especially in High Temperature Alloys such as titanium, 4140, steels and
Unstable materials are “substances that start at a relatively low hardness point and are then heat treated to promote the growth of hard particles inside the original matrix, which increases the overall hardness of the material at the expense of some its original toughness. Since heat is the mechanism to alter the structure of the substance, and at the same time the cutting action produces a lot of heat, such substances are inherently unstable under machining conditions”.
Stable materials on the other hand are “substances that remain relatively stable under the heat produced by most machining conditions, as they don't attain their hardness through heat. They wear down due to abrasion, but generally don't change their properties much during use” .
Most stable materials tend to be hard and very fragile and are generally used for large, heavy and stiff machinery.
Unstable materials tend to be softer and thus tougher and are generally used in hand tools and light machinery.
The main materials used for cutting tools …show more content…
They are composed of a base mineral or petroleum oil and often contain polar lubricants such as fats, vegetable oils and esters as well as extreme pressure additives such as Chlorine, Sulphur and Phosphorus. Straight oils provide the best lubrication and the poorest cooling characteristics among cutting fluids.
Synthetic Fluids
They contain no petroleum or mineral oil base and instead are formulated from alkaline inorganic and organic compounds along with additives for corrosion inhibition. They are generally used in a diluted form (usual concentration 3 to 10%). Synthetic fluids often provide the best cooling performance among all cutting fluids.
Soluble Oil Fluids
They form an emulsion when mixed with water. The concentrate consists of a base mineral oil and emulsifiers to help produce a stable emulsion. They are used in a diluted form (usual concentration 3 to 10%) and provide good lubrication and heat transfer performance. They are widely used in industry and are the least expensive among all cutting fluids.
Semi-synthetic Fluids
They are essentially a combination of synthetic and soluble oil fluids and have characteristics common to both types. The cost and heat transfer performance of semi-synthetic fluids lies between those of synthetic and soluble oil …show more content…
In this application pressurized liquid CO2 is allowed to expand and following the ideal gas law, this is accompanied by a drop in temperature, enough to cause a change of phase into a solid. These solid crystals are redirected into the cut zone by either external nozzles or through-the-spindle delivery, to provide temperature controlled cooling of the cutting tool and work piece. Existing CNC machines can be retrofitted with this safe and environmentally coolant approach. In applications such as turning, milling or drilling tool life and throughput have been improved substantially, especially in High Temperature Alloys such as titanium, 4140, steels and