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Prolong the service life of the die and its solutions

By using PVD coating, the problem of mold sticking was solved. Originally, the mold was cleaned once in 2h, and once in 2 days after using CrNC coating; after using the improved NF1 coating, the machine was cleaned once in 5 days. This not only solves the problem of difficult mold exit, but also reduces downtime and saves mold time, and improves the quality and stability of finished products. The service life of the mold is greatly increased, and the production efficiency is obviously improved.
PVD is the physical vapor deposition method, and PVD coating is the surface coating made by physical vapor deposition method.
Application in plastic moulds
The durability of plastic molds is of greater concern due to their high requirements. PVD coating has unique lubricity and high hardness, which can greatly improve the above problems encountered in the production process.
Beryllium copper is characterized by fast heat dissipation and hardness generally up to Rockwell 40. fast heat dissipation (3 times faster than steel) means that injection molding production cycle time can be shortened and output is higher. Beryllium copper is expensive, more expensive than the average plastic steel, so any wear, scrap or resharpening costs are high. Based on the hardness cannot exceed Rockwell 40, so surface wear is the more serious problem it encounters. Considering the hardness and the characteristics of beryllium copper, the coating company specially designed a perfect PVD coating solution TiN-BeCu for beryllium copper molds or inserts, which improves the surface wear resistance of beryllium copper without reducing its high thermal conductivity.

Fig. 1 Mr. Ye Shu, technical director of Elite and Mr. Guo Guangyu, CEO of Techmart, discussing the coating solution in the meeting room of Elite
Today's trendy consumer products such as digital cameras, laptops, cell phones or PDA products are particularly functional, but the appearance is developing in the direction of small and delicate, so the requirements of such products are high in terms of precision and material selection. In the selection of materials, based on the high protection performance of the shell and the internal high strength, generally use PC + ABS + glass fiber material. The material is highly abrasive and corrosive to the mold. In addition, plastic molds are generally tempered at low temperature, so all high temperature treated PVD coatings are not suitable. In this case, CrNC is the best choice. CrNC has high resistance to chemical corrosion and its hardness is not less than HV2000, which is enough to cope with the hardness required by plastic production and is the best choice for plastic moulds. Meanwhile, precision mold inserts are characterized by small errors and deep grooves, and it is not easy to achieve no deformation and balanced coating. Coating company knows the application of plastic moulds well, so they will apply CrNC coating to solve the problem of mould wear for customers.
Clear plastic bottles are typical mass-produced products, and their molds have particularly high surface requirements for high speed production, such as high surface hardness, polishing to mirror finish and good mold release ability. Generally, European and American manufacturers are willing to use Mirror-Gold PVD coating to enhance the hardness of the mold surface and improve the lubrication and mold release ability. Due to the high hardness and good lubrication performance of PVD coating, it can shorten the production cycle and increase the output.
Today's automakers are looking for ways to reduce the total weight of their vehicles to save fuel without compromising safety and quality. Engineering plastics are lightweight and strong, making them a good material for automotive parts. However, when it comes to the production of engineering plastics such as nylon or glass fiber added products, the surface wear is particularly severe regardless of the type of mold steel.
Founded in 1988, Elite is a Hong Kong-owned precision mold manufacturing group company and one of the leading companies in precision plastic molds. Specializing in the fields of mold making, injection molding, spraying, plating, silk transfer printing, assembly and packaging full service comprehensive enterprise group, product five product business groups (quality life, packaging, automotive, power distribution, medical business group), dedicated to the world's top 500 companies to provide one-stop, first-class products and services.

Figure 2 NF1-coated molded parts
In fact, at the beginning, Elite had a batch of molds for auto air conditioning parts that had many problems during injection molding. At the same time, in order to maintain the quality of the finished products, the mold had to be cleaned every 2 hours. It was difficult to maintain the quality of the product and the production was very inconvenient. At this time, Elite found the PVD technology promoted by Techmart Nanotechnology Co.
By using PVD coating, Elite solved the problem of mold sticking. Originally, the mold was cleaned up once in 2h, and once in 2 days after using CrNC coating; after using the improved NF1 coating (Figure 2), the machine was dropped once in 5 days for a big cleaning. This not only solved the problem of difficult mold exit, but also reduced downtime and reduced mold saving time, and improved the quality and stability of finished products. The service life of the mold is greatly increased, and the production efficiency is obviously improved.
Application in hardware moulds
The mold industry can be roughly divided into three categories: hardware molds, plastic molds and die-casting molds. For hardware moulds, because the hardware industry generally needs to punch holes and pleat bend molding on thin metal sheets, etc.. Commonly used stamping accessories, such as punching bar, often rub with the processed material. In order to prolong their service life, most of them need to use PVD coating on the surface.
Hardware stamping is used to punch thin metal sheets into different shapes by the principle of shearing. Depending on the process, abrasion, plastic deformation and chipping are all mechanisms of damage, so the ideal stamping die must have both high hardness and high toughness. High hardness ensures good wear resistance and good toughness means good chipping resistance.
Based on the physical property limitations of die steel, such as the commonly used D2 material, which has a hardness of over HRC62, the use of TiCN-MP PVD coating is the best way to improve the surface wear resistance, for example, titanium nitride PVD coating can reach a surface hardness of HRC85, which has a direct role in helping to solve the wear problem. However, the plastic variation also needs the hardness of the substrate to bear. Punching bar is a common die used for stamping, and TiN-Mirror and TiCN-MP coatings are generally used.

Fig. 3 After using the coating: The customer is very satisfied that the coating can increase the die life more than 3 times and improve the release effect
Good hardware drawing dies require high hardness and good lubrication surface. TiCN is a good tensile coating, its hardness can reach Hv3700, but the friction coefficient can be lower than 0.2.
Application in die-casting moulds
The production conditions of die casting die are the most severe, in high temperature metal solution, through high pressure injection, and the die surface keeps on thermal expansion and contraction, which leads to the short service life of die casting die, and the need to repair and maintain the die constantly during production.PVD TiAlN-F3 coating can solve some of the problems encountered by die casting die, but the effect of extending its life is relatively worse than that of tool. The coating company has developed a new technology of PVD coating pre-treatment for this problem, and has achieved some success in improving liquid metal sticking to the mold and thermal cracking.
Coating is to increase the cost of manufacturing the mold, accounting for 10% of the total cost of the mold. However, if we calculate the total cost of producing each product, because of the efficacy of the coating, the life of the mold is extended several times, and the mold release is easy, the downtime for mold maintenance is reduced, etc. (Figure 3), and the production volume is doubled or the production time is shortened, then the production cost of each product must be much lower.