Topics & News Release

Toyo Advanced Technologies Co., Ltd. (Head office: Minami-ku, Hiroshima City, President: Yuichi Hayano) has developed and begun full-scale sales of our new "PVD TiC-X" film for dies. PVD TiC-X was developed by optimizing the film structure of our PVD TiC film, which is widely used in press dies. This new film improves the service life of dies, allowing them to withstand use under high-load press conditions when processing ultra-high-tensile strength steel sheets.

Due to safety and environmental concerns, the automobile industry is increasingly adopting materials that have high strength, high rigidity, and are lightweight. The use of high-tensile strength steel sheets is increasing as it satisfies these requirements. As high-tensile strength steel sheets are stronger than ordinary steel sheets, the dies are subjected to higher loads during press forming. Due to their high hardness, the sheets slide across the die surface under an extremely high pressure. As high-tensile strength steel sheets continue to become even stronger, there is an increasing demand for coatings that can withstand such harsh press forming conditions in order to achieve stable mass production for press forming processes.

PVD TiC-X is a special type of TiC (titanium carbide) film that has excellent resistance against fracture and wear. It was developed by utilizing our cathodic arc ion plating furnace (TF-778N). PVD films are formed by using plasma to vaporize and ionize the coating material so that it is electrically attracted to a substrate to which a negative voltage was applied. However, this process results in residual compressive stress, making it difficult to form thick films. During the development of PVD TiC-X, we reformulated and optimized the film structure so as to take advantage of the excellent wear resistance of conventional PVD TiC while also achieving high strength with an approximately twofold film thickness.

［Features of PVD TiC-X］

A longer service life when press forming 1.5 GPa ultra-high-tensile strength steel sheets

The performance of PVD TiC-X was evaluated using 1.5 GPa steel sheet under high-load processing conditions with a maximum surface pressure of 900 MPa. As a result, there was no breakage (cracking or peeling) during continuous processing equivalent to 320,000 shots. As for wear resistance, it was calculated that 560,000 shots are required to cause 1 μm of coating wear. This confirmed that the coating has sufficient life performance against any form of failure.*

We used the latest 1.5 GPa steel sheet to verify the performance of PVD TiC-X for high-load press processing geared toward mass production. This means that press engineers do not need to worry about its suitability for such applications. Since its release, it has been experimentally adopted for press dies used to form high-tensile strength steel sheets and high-thickness materials where it is steadily building a solid track record.

* Verification of life performance in the case of mass production

When a new coating is developed, its performance is generally determined by checking the physical properties such as film hardness, and then subjecting it to basic evaluation testing such as friction and wear tests. However, the conditions during these evaluation tests can never perfectly replicate the actual conditions during mass production press forming. Therefore, such performance may not be realized in a real production environment. In order to more accurately verify the life performance that would be seen in real-world mass production press forming processes that are required by our customers, when developing PVD TiC-X, we conducted durability testing through a continuous press forming process using 1.5 GPa steel sheets. This is the strongest high-tensile strength steel sheet used in cold pressing. In addition, the die used for this test was designed using CAE analysis in order to reproduce the high surface pressure of mass production press forming. By independently developing a technique to continuously apply a stable high surface pressure load to the die during press forming, we achieved accelerated testing. We also verified the life performance during mass production press forming by evaluating the coating fracturing and wear under conditions similar to the end of its service life.

In 1968, Toyo was the first manufacturer in Japan to successfully develop a CVD (chemical vapor deposition) coating. In addition to CVD, we are currently a comprehensive coating manufacturer with equipment for PVD and ultra-large equipment for nitriding (PPD). While the market for PVD coatings is expanding, competition is becoming more fierce as various companies introduce new and strategic products. In 2014, Toyo developed our own PVD furnace (TF-778N) and has since been working to improve the product appeal of our PVD TiC coating and develop new products. Our new PVD TiC-X coating is a strategic product that was developed using this equipment, and we plan to continue to flexibly respond to trends in the market, develop attractive products that satisfy customer needs, and further strengthen our product appeal.

「PVD TiC-X」is here