Die steel: matrix for die manufacturing (I)

As China’s economy continues to grow at a high speed, the domestic mold manufacturing industry is growing faster than GDP. This has also provided a huge market for the development of domestic die steel, driving the rapid improvement of the domestic die steel production, variety, specification and quality level. As the matrix of die manufacturing, the performance of die steel has a direct impact on a series of factors such as the service life and production cost of the die, and has been paid more and more attention by die manufacturers.

Research and Development of New Cold Working Die Steel

Mr. Anda Qianyi: The automobile industry has always been considered as the driving force of industries in various countries. At present, in order to achieve the goal of lightweight and safety design, automobile manufacturers are rapidly expanding the effective use of high strength steel plates (super hard, super strong). However, from the difficult formability of stamping itself, the problem of die life is increasingly put on the agenda.

On the other hand, it is extremely urgent for the mold industry to reduce the cost and shorten the delivery period. Therefore, both industries are most eager to develop mold materials that are easy to cut and have less dimensional deformation after heat treatment. Hitachi Metal has developed the next generation of cold work die steel, SLD-MAGIC, which is far beyond the characteristics of common material SKD11, by combining the experience and development force accumulated from more than 100 years of steel making.

Through the comparative test with SKD11 improved steel 8% Cr steel (SLD8, our company’s commodity), the new high-performance cold work die steel SLD-MAGIC has shown considerable advantages in improving die life, reducing the total cost of die production and shortening the delivery period. It is mainly reflected in the following aspects:

– Wear resistance: the highest hardness is HRC62, and its wear resistance is increased by about 35%, which greatly improves the service life of the mold.

– Surface treatment: the tightness of the surface treatment film (CVD and other methods) is increased by about 30% to prevent scratches generated during the bending, stretching and other forming of high-strength steel.

– Heat treatment characteristics: the heat treatment inch change will be reduced by about 40%, and the shape deviation will also be improved. For heat treatment and surface treatment, the size deformation is less and the repair time is reduced.

– Machinability: the machinability is increased by about 35%. Based on the improvement of processing efficiency, the processing time in mold manufacturing is shortened.

The above characteristic values of wear resistance, heat treatment property, surface treatment property and machinability are representative data compared with SLD8, which may be slightly different from the actual product characteristic values.

The rapid development of die and mould industry puts forward new requirements for die and mould steel

Dr. Li Shi: Generally speaking, in addition to the drawings, the technical standards also include the selection of mold materials, the specific process of heat treatment, the control of electrical discharge machining, the surface roughness, and the surface treatment of mold components (such as die casting thimbles). This requires that the die steel supplier can provide high-performance die steel for different application needs, and can communicate with the die manufacturer about the process requirements specified in the die manufacturing technical specifications other than material properties, such as surface coating process. Auber Dewar Mold Technology (Wuxi) Co., Ltd. can provide high-quality mold steel produced by Auber Dewar in France to mold manufacturers, and the existing sales team can communicate with those mold manufacturers to meet the technical specifications specified by foreign buyers. The company provides hot mold steel, cold mold steel, plastic and glass mold steel. In some applications, such as high-pressure die casting molds, Auber Dewar has its own production technical specifications. The products are designated and recognized by European and American automobile manufacturers. Its product quality is higher than the technical specifications of European and American industries (such as the specifications of NADCA North American Die Casting Association) and ensures the stability and long-term life of the mold. In this application, the ADC3 of Ober Dewar brand is especially suitable for those large mold applications. At present, one of the development trends of automobile industry is to use die casting to manufacture large aluminum and magnesium alloy parts, such as automobile engine block. For manufacturing such products, the thickness of die steel shall be more than 300mm, and three-dimensional forged steel shall be the first choice. Ober Dewar Factory has its own uniqueness in 3D forging, thus ensuring the uniformity of 3D performance of materials used. In addition, SMV3W (1.2343ESR) and SMV4S (1.2344ESR) of Ober Dewar brand are also designated by automobile manufacturers. In Europe, the above three types of products have shown good performance in practical application and extended the life of the mold, thus reducing the cost and price of single parts. In some applications, such as the production of automobile gearbox housing, the service life of the die made of ADC3 steel has reached more than 200000 pieces, much higher than the common 1.2344ESR steel.

In the application of plastic mould, the steel X15TN produced by Ober Dewar adopts the manufacturing process of nitrogen replacing carbon alloy element, which ensures the excellent polishing performance of this steel. X13T6W (S236), MEK4, SMV3W are used on reflective plastic parts of automobile lamps, which have excellent polishing performance and no common pinhole phenomenon. The impurity content of each steel is very low, and the impurity sulfur (S) content of the product is within 5PPM, and the oxygen content is within 10PPM.

With the rapid development of mold manufacturing industry, mold suppliers must have the ability to provide high-quality, high-performance mold materials to meet customer requirements. At the same time, the supplier must have a sales expert team to provide customers with system application suggestions. In this regard, Ober Dewar can provide customers with excellent products and services to promote the improvement of the whole mold manufacturing level.