top of page

Everwide Newsletter No.215

Updated: Jul 30, 2021


Experiment § Testing composite bending

The bending test can detect the rigidity, elongation, and Young's coefficient of composite materials, so this type of test data is often used for material evaluation. The test piece is first laminated with a prepreg cloth, and when it reaches the desired number of layers, it is placed in a mold for hot pressing (100 layers in Fig. 1), and then subjected to a bending test with a universal testing machine. Composite materials have several failure modes in bending tests, such as compression, tension, plastic deformation, and delamination. Figure 2 shows that the upper clamp surface is under compression, and the lower clamp surface is under tension. Compression failure is common in the upper layer of the test piece, and interlayer peeling is common in the lower layer. The compression surface of the upper layer is not supported by fibers and the resin with lower modulus is prone to damage (Figure 3); The tensile surface of the lower layer of the test piece will not be easily broken due to the high modulus of the fiber, but the direction of deformation is opposite to the upper layer, so interlayer peeling will occur (Figure 4). At present, this method is designed by ourselves. According to the ratio of ASTM D2344 short beam test piece, it is enlarged to the size of ASTM D790. This experiment allows us to evaluate the toughness of the resin, the bonding of the fibers, and the strength of the composite. In the future, we will design appropriate letters and use the short beam shear mode of standard ASTM D2344 for further experiments.

—Mr. Zhi-Xuan, Chen

 

Activity § Viya and year-end meeting

Viya and year-end meetings were the two most important things last year. Colleagues Viya bring their families and arranged 22 banquet tables. There are newcomers introducing themselves and old people drawing prizes. As usual, the boss promised that the red envelopes he drew would be "donated," and everyone cheered. The boss also reminded everyone that there is an opportunity to donate some to people in need of help in society. Regarding the latter, everyone thinks seriously. At the year-end meeting, various departments reported what they had achieved last year and how they should learn this year. One of the themes is closely related to the study trip everyone went to Japan last year. What is the difference between Taiwan and Japan? What should we do to make progress like others? Of course, when the 215 issue was published, these discussions were over. The theory lies in practice, and it depends on how we do it this year.

 

Knowledge § Where does the pollution of silica gel come from?

Silicone rubber, silicone resin, silicone oil... and other products are polymerized from raw materials such as Hexamethylcyclotrisiloxane (D3) and Octamethylcyclotetrasiloxane (D4), and these productsall contain these monomers, which are easily found in the GC-Mass map. This type of monomer will slowly evaporate and is classified as contamination of Cyclic silicones. Another source of contamination is silicone oil in silica gel. Adding silicone oil to silica gel can adjust the viscosity and flexibility, but oil leakage will occur on the surface for a long time, and it may volatilize and cause pollution. These pollutions often cause damage to electronic components. For example, the contact resistance of relays will gradually increase due to these pollutions. Common MS resin products on the market, although MS is the abbreviation of Modified Silicone, the main chain structure has nothing to do with silica gel. Most of them are polyether or acrylic structure, so they will not have pollution problems like ordinary silica gel. MS resin is bridged by the reaction of the silane functional group at the end, and its behavior is similar to that of silica gel, hence the name.

 

Living § Home treasure

I still remember the moment when the doctor rescued my grandma in the emergency room three years ago. Grandma fainted due to severe water in the lungs and was given emergency care in the hospital. It was my birthday, and all my wishes were about grandma. I prayed that God would give us a miracle and hope that her old man would return to us so that we can continue to take care of her. Fortunately, God heard my prayers, and grandma was discharged from the hospital after a month in the hospital. Since I was a child, what impressed me most was that my grandmother would run 3,000 meters in the morning every day. It wasn't until five years ago that we banned her from running in the morning because her health was deteriorating. I am used to talking with her on the phone every day because I am worried that one day she will forget me. In order to chat with her, I tried to learn Taiwanese, and I also spoke Taiwanese better and better. What surprised me the most about my grandmother was that she still has a very good memory, and sometimes even pretends to be satellite navigation to lead me. My grandmother's naive and innocent personality infects me from time to time. She always teaches me a lot of truth in life. Recently, the issue of long-term care has been fermenting. For many people, long-term care is a heavy burden. The government's subsidy measures are diverse and although helpful, they are often confusing. My friend asked me, "Isn't it tired to take care of the elders?" In fact, I am not tired at all, and I am full of happiness! For a long time, I rushed back and forth between two places every day. My body is sometimes very tired, and I often drive until I fall asleep. However, when I saw my grandma's body getting better day by day, I was excited. Now, grandma can take selfies with me! Companionship is the best medicine. If the mentality of taking care of the elderly is correct, we will not feel too tired. We should all cherish the treasures of the family. Cherishing everyone around us is compulsory homework for our life. For more information about long-term care: http://www.ltcpa.org.tw/public/main.php

—Author:Miss. Heng-Rong, Li



9 views

Related Posts

See All

Comments


Related Products

bottom of page