PVD Coating on Bimetal Band Saw Blades
With the development of the national economy, the manufacturing industry has higher and higher requirements for processing efficiency and precision. However, in the past decade, the efficiency improvement of bimetallic band saw blades has been very limited. This is mainly because the research of the band saw industry is mainly focused on manufacturing processes (coding, welding, heat treatment, etc.), tooth design, cutting mechanism (including cutting force research, failure mechanism analysis, vibration analysis, sawing process analysis) and other aspects. It is because the raw materials have not changed much in the past 20 years. The backing material is mainly X32 spring steel, and some high-end products use B318 spring steel. The tooth material is mainly M42 high-speed steel, and some high-end products use M51 high-speed steel. This limits the revolutionary improvement of the performance of bimetallic band saw blades. On the other hand, other traditional cutting tools, such as lathes and milling cutters, have made great progress not only in materials (such as the wide application of cemented carbide and metal ceramics), but also in surface strengthening (such as coating technology) and efficiency. , The processing accuracy and tool life have been significantly improved. High-speed milling technology is also developing rapidly.
Band saw blades use flexible spring steel as the saw tooth base to support the cutting force. If the cutting force is too large, the base will bend and deform greatly, resulting in excessive cutting verticality error. In the case of wide-gauge saw blades, the saw blades are narrow and long, and cannot be fully cooled, resulting in high cutting temperatures. Therefore, solving problems such as improving the heat resistance, wear resistance, and cutting speed of saw teeth is an important direction for improving the efficiency and service life of band saw blades.
The physical vapor deposition (PVD) method used to prepare hard coatings has played an important role in improving the life and efficiency of traditional cutting tools. PVD coatings have doubled the performance of coated lathes and milling cutters. However, there are few reports or studies on the application of PVD to band saw blades.
The properties of the saw tooth base material are very important for protecting the coating. Since band sawing generates large vibrations, increasing the toughness of the saw blade by adjusting the material selection or heat treatment can reduce the chance of saw blade breakage and improve the performance of the coating.
The AlCrN coated bimetallic band saw blade obtained by PVD technology has increased the sawing area by 20.4%. The coating can effectively protect the front cutting surface of the saw blade and reduce the width of saw blade wear. The performance of the coating is related to the material and properties of the sawtooth substrate. Reducing the damage of the sawtooth during the cutting process can give full play to the performance of the coating.
