Experiment § Open type high temperature resistant rigid foam
Foaming products can be classified according to structure (open and closed) or material (silicone, rubber, epoxy, PU, etc). There are fewer high temperature resistant foam materials. Polyimide (PMI) has light weight, closed cell, hard, excellent mechanical and temperature resistance (180-240℃), so it is often used as the core layer of structural composite materials. Processing the foamed PMI board will waste a lot of trim; plus, the raw material itself is expensive, so it cannot be widely used. Everwide developed the epoxy hard foaming NF702, which uses resin and foaming powder to mix uniformly (Figure 1) and processes into a soft and flexible sheet material (Figure 2). After heating (150°C/30 minutes), a lightweight foam material (Tg=140°C) with properties of rigidity and heat resistance was obtained. Furthermore, different resin structures have different surface characteristics. In Figure 3, the foam material on the left has a smooth surface, and the foaming material on the right has holes. Since the main body of the foam material is epoxy resin, it has better adhesion with carbon fiber and glass fiber epoxy resin prepreg. Figure 4 shows the internal condition of the cross-section of the foam material. The characteristics of dense structure and high Tg make the foam material difficult to soften and deform at high temperatures.
─Author: Jung-Hsin, Lin
Activity § IATF 16949 Internal audit
The new version of IATF 16949 has stricter requirements for internal auditors than before (Article 7.2.3). Its purpose is to ensure that the personnel can continue to have the competence. In addition to being familiar with audit methods, customer special requirements, regulatory requirements, and five core tools, it is also key to participate in a certain internal audit activities each year. We adopt a two-person team approach in internal audit activities, so that we can maintain better objectivity during the audit process. What's more, it can quickly expand the actual experience of internal auditors and allow more colleagues to have other skills in addition to their own work skills. During the internal audit process this year, we could see many colleagues discussing the implementation of the process together. By examining the records, we can discover potential risks and improve early.
Knowledge § Shrinkage and shrinkage stress
There are many definitions of shrinkage, such as shrinkage when liquid becomes solid, shrinkage when solid is cooled, shrinkage caused by mass loss, etc. Briefly, it is caused by volume changes. During these shrinking processes, some materials exhibit soft, rubber-like properties. In these cases, even though the shrinkage rate is large, the shrinkage stress is actually very low. When shrinkage occurs in the glassy state of the material, the rigidity of the material is very high, so even if the shrinkage rate is not large, there is a large shrinkage stress. In other words, the shrinkage rate and shrinkage stress are not necessarily related.
Living § My trip in Africa (2)
Our real volunteer journey was about to begin. Moving to kitale in northwest Africa was the first stop. This was a long journey. After a few bumpy and rugged vehicle conditions, I had already told myself to adapt to the ups and downs of hills and unpaved ground. We passed the beautiful tea plantations along the way, and occasionally saw women selling agricultural products on the side of the road. What made me wonder was the iron windows and iron doors sold on the roadside, and people wearing yellow helmets and riding motorcycles. Needless to say, they were drivers who were doing business. First of all, we must first went to the house rented by the Step30 organization, which is also the base for volunteers to come to Kenya. Then we went to a village, which is a temporary sanitation instruction place. Medical staff required villagers to clean their homes regularly, and wore shoes to protect their feet from Tungiasis. If you saw a little girl having her hair trimmed, it was actually the nursing staff helping her to clear her sores. Because sand fleas not only lived on her feet, but also lived on her ears and scalp.Therefore, nurses must removed her hair before disinfection. Because the process was painful, her thin body was twitching, but the brave girl did not cry during the treatment. One earth but two worlds. In faraway countries, children live like this!
─Author: Miao-Ling, Lin
