Everwide Newsletter No.234

Experiment § Application of epoxy soft glue in soft-club

The impact deformation between different types of softballs and bats is not the same, and the hitting distance is also different. Therefore, the design of hard and soft bats is different. For example, choosing a hard metal bat with excellent rigidity to play may not be far because the contact time between the softball and the bat is too short (Figure 1). The newly designed bat uses carbon fiber as the body and is coated with high-density foamed PU/EVA material (Figure 2). When this kind of club hits the ball, the foam layer will deform first and then rebound, resulting in a great reflex coefficient (reflex coefficient refers to the ratio of the relative speed before and after the collision of two objects). When the PU/EVA outer layer composite bat is used for a long time, the foam layer may cause depressions in a strong impact, making the durability of the composite bat criticized (Figure 3). Everwide provides a soft epoxy resin, which is flexible and has a good connection relationship with fibers, which can improve the depression and deformation of the foam layer. When you play next time, you can use force as you like, and you don't have to worry that the bat will be easily broken.

—Author: Mr. Kai-Quan, Zhuang

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Activity § Apple Inc's visit

At the end of October, the market value of the largest companies in the world the US Apple (Apple Inc.) material department managers and senior engineers to visit our factory. Paul and James explained that the reason for their visit is that Apple's products are assembled by foundries, and some of our products appear in the list of materials for Apple products (BOM; Bill of Material). They hope to understand what kind of factory Everwide is. On the one hand, they can grasp the trustworthiness of Apple products and have opportunities to cooperate in development in the future. Visitors leave amazing comments on our equipment and training system, we will continue to work hard.

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Knowledge § The scope of application of hypoxia glue

Hypoxic glue is cured by the decomposition of peroxides to generate free radicals and undergo a chain polymerization reaction. This reaction has two key points. The first is that the decomposition of peroxides requires metal components as catalysts. The second is that the adhesive needs to isolate oxygen so that free radicals will not react with oxygen to form peroxides and stop the polymerization reaction. The use of oxygen-deficient glue to bond metals can fully meet these two requirements. The activity of some metals is relatively slow, or some materials have no metal components, such as ceramics, which can be overcome by primers. Use the components of hypoxic glue to connect rubber and plastics with great care, because some rubbers and plastics have poor oxygen isolation ability, which will make the reaction rate of hypoxic glue very poor and some plastics are very sensitive to anoxic adhesive monomers (methyl methacrylate, MMA), and the curing process of anoxic adhesives will corrode some plastics, causing the plastics to crack in the future. The oxygen-deficient glue is probably no problem when used on inorganic materials, but you must be careful when using it on organic materials. Extended reading: Bi-weekly report 165: What is the truth of UV glue + anaerobic?

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Living § Changbai Mountain Tour

This time I was fortunate enough to follow my classmates to teach in Northeast China for seven days, visit schools and companies for four days, and discuss and exchange with each other. We left for three days to plan the trip to Tianchi in Changbai Mountain. However, there is only one-fifth chance to see Tianchi in this season. With the mentality of giving it a try, we went up the mountain to take a look. Along the way, the tour guide comforted everyone. The weather report has been very snowy in the mountains these days, so we must be mentally prepared. In case we can't go up the mountain to see Tianchi, we may have to rest earlier. After a seven-hour trek, we arrived at Erdaobaihe Town under Changbai Mountain to rest, and then drove to the mountain the next day. Before arriving here, it had been snowing for five consecutive days, and it was not clear whether I could go up the mountain. Until ten o'clock in the morning, the park informed us that we could go up the mountain, and the passengers who took the first bus were all excited. The park is planned to adopt a shuttle bus to connect to the top of the mountain with a seven-seater mountaineering jeep. The driving master’s skills are really great, winding up the mountain along the way, and seeing the white snow scene, it feels really beautiful right now. We are really lucky to be able to see the beautiful view of Tianchi! This is also the first time in my life that I have seen such a white and beautiful mountain view and the natural beauty of Tianchi. I am very moved! The environmental protection here is quite good, and many virgin forests are well preserved. This is the result of the efforts and cooperation of many people. Thank God for your blessings, let us get our wish and enjoy the world's 5A-class beauty.

—Author: Mr. Can-Xian, Hong