Stainless steel is also called SUS (Steel Special USE Stainless), and is an alloy mixed with iron and nickel to improve strength and durability. By adjusting the elements to be added to the iron, various characteristics can be given, and the type is more than 100 types of JIS standards alone. Typical ones include a "austenite system" mixed with chrome and nickel, and a "ferrite system" that does not contain nickel. This article describes the characteristics of stainless steel known as difficult shaving and measures for stainless steel cutting.
Stainless steel has high corrosion resistance by producing oxide films on the surface. It has a longer life than other ingredients, reducing the frequency of maintenance and replacement of parts. In addition, because it is stronger than iron and steel, it is used in building materials, and it is also used as a material for dishes such as tableware because of its high heat resistance. On the other hand, processing stainless steel is not easy. Various metal processing, such as pressing and welding, is used for stainless steel processing, but is known as a difficult cutting material in cutting.
Stainless steel is characterized by a low thermal conductivity, and it is difficult to escape heat (= cutting heat) generated by cutting, so that the temperature of the cutting point is likely to increase. Excessive cutting heat also affects the coaching material and cutting tool, and the heat expansion may increase the cut depth of the coveting material and shorten the life of softened cutting tools. In particular, the austenite stainless steel is likely to cause processing and curing by converting it into malten sites (changing to a hard and brittle tissue) during cutting. In addition, because of its high option, the material is difficult to break when cutting, and it transforms flexibly. When cutting stainless steel with such characteristics, the following tasks occur.
The low thermal conductivity of stainless steel causes issues such as promoting wear of wear and deteriorating processing accuracy.
The heat generated when cutting stainless steel is around 800 ° C to 1200 ° C, depending on the condition at the time of cutting. If the temperature of the cutting point is high, the "weld" that some of the work that has melted during the cuttings adheres to the tool is likely to occur. As the weld progresses, it causes chipping (small chipping) of the edge to promote the wear of the blade.
Cutting heat is concentrated on the processing point, causing warp and distortion in the stainless steel. If you continue processing in this state, the processing accuracy will worsen as much as the warpage or distortion occurs.
The processing of the stainless steel can lead to a tool wearing and breaking the work.
One of the factors that affects the wear of tools is the relationship between the hardness of the tool material and the work material. When cutting stainless steel, processing and curing the work will make the tools worn out.
Stainless steel loses extension and becomes brittle by processing and curing. The brittle materials are easy to lead to cracks and broken, so care must be paid to the cutting conditions at the time of processing.
Due to the highly expandable stainless steel, poor processing generated during cutting and wear of tools occur.
Cutting of the work generated during cutting makes it difficult to refuse if the material is expanded. The difficulty of draining cut powder causes various problems caused by cutting powder, such as scratches on the work surface and deterioration of processing accuracy.
High -exhibition is highly difficult for stainless steel to tear when cutting, so that the load on tools is high and worn is more likely to progress.
This section describes how to deal with the low thermal conductivity, processed and cured, and high exhibitions that are characterized by stainless steel.
As a countermeasure against the task caused by the low thermal conductivity, the use of oil mist is used and the cutting conditions are changed.
By using an oil mist during cutting, you can expect cooling of the cutting point. Since the temperature of the cutting resistance and the cooling effect are less likely to rise, even stainless steel with low thermal conductivity can suppress the wear and the deterioration of the processing accuracy.
By removing the cutting conditions, the temperature rise at the point of cutting can prevent the temperature rise. The processing time will be longer by slowing the sending speed, but the temperature rise can be suppressed, so even stainless steel with low thermal conductivity can suppress the wear and the deterioration of the processing accuracy.
As a countermeasure against issues caused by processing and curing, coating tools and oil mist are used.
Select a coating tool with high abrasion resistance to suppress the wear of tools caused by stainless steel cure. In particular, the coated ultra -high tools have excellent wear resistance and are ideal for processing stainless steel.
Processing and curing is more likely to occur when the temperature of the cutting point is high, so use an oil mist to cool it. By suppressing the temperature rise at the cutting point while reducing the cutting resistance, the occurrence of processing and curing is reduced.
It is important to select a sharp tool with a large scooping corner for measures against high exhibition. It is ideal for scooping horns to be 30 degrees or more, but on the other hand, it is easy to cause damage and chipping, so it is necessary to pay attention to cutting conditions and cutting amounts.
In this article, we explained the characteristics of the stainless steel, which is a difficult cutting material, and the tasks and countermeasures during stainless steel cutting. Stainless steel has attracted attention even with high antibacterial properties in addition to excellent corrosion resistance. As stainless steel processing increases, the metal processing industry needs to know the characteristics of stainless steel and use various processing methods.
