ما هي العوامل التي ستؤثر على آلية تجميع ثنائي الفينيل متعدد الكلور؟
تاريخ النشر 2020-07-07من اندماج المواد ، تخطيط ثنائي الفينيل متعدد الكلور ، تصميم النموذج الأولي ، هندسة ثنائي الفينيل متعدد الكلور ، تجميع ثنائي الفينيل متعدد الكلور إلى مرحلة التعبئة والتغليف وتسليم الطلبات ، يجب الانتباه إلى تأثير الرطوبة في تصنيع ثنائي الفينيل متعدد الكلور لتجنب التلف والمشاكل الأخرى لوظيفة ثنائي الفينيل متعدد الكلور. بالإضافة إلى ذلك ، دعونا نفهم بعمق الإجراءات المهمة للتحكم في مستوى الرطوبة أثناء عملية التصفيح ، والضوابط التي يتم تنفيذها أثناء تجميع ثنائي الفينيل متعدد الكلور والتحكم في التخزين والتعبئة والنقل.
Rigid/flexible printed circuit board components, cable harnesses, boxed components or wire harness ثنائي الفينيل متعدد الكلور components are made of various types of materials. These materials fully meet the attributes required for strong mechanical and electrical performance in electronic products used in all major industries around the world . It requires high frequency, low impedance, compact, durable, high tensile strength, low weight, multi-function, temperature control or humidity resistance. PCB is divided into single layer, double layer or multiple layers, depending on the complexity of the circuit. Among all serious issues that should be noted in the initial stages of PCB manufacturing. Humidity is the main factor that leads to space for electrical and mechanical failures in PCB operations.
How does moisture cause trouble on PCB assembly?
By being present in the epoxy glass prepreg, it diffuses in the PCB during storage, and when absorbed, moisture can form various defects in the PCB assembly. The wet process time in theتجميع ثنائي الفينيل متعدد الكلور process exists in micro-cracks or can form a home in the resin interface. Since the high temperature and steam pressure are parallel to the lead-free mechanism in تجميع ثنائي الفينيل متعدد الكلور , it will cause moisture absorption.
With the adhesive and cohesive failures in the printed circuit board leading to delamination or cracking. Moisture can make metal migration possible, resulting in a low impedance path with varying dimensional stability. As the glass transition temperature decreases, the dielectric constant increases and more technical damages occur. It causes a reduction in circuit switching speed and a high propagation time delay.
The main effect of moisture in PCB assembly is that it reduces the quality of metallization, lamination, solder mask and PCB manufacturing processes. Due to the influence of moisture, the limit of thermal stress becomes excessive as the glass transition temperature decreases. Sometimes it can also cause severe short circuits, which can lead to water ingress and ionic corrosion. Other common properties of hygroscopicity in printed circuit board components include flame retardancy or delamination, increased (DF) dissipation factor and (DK) dielectric constant, thermal stress on plated through holes, and copper oxidation.
Method for reducing moisture in PCB manufacturing
Regardless of whether PCB manufacturing uses simple or complex technologies, there are many operations in PCB engineering that require wet processes and removal of residual moisture. The raw materials used in PCB manufacturing need to be protected during storage, handling, and handling stress during PCB assembly. The following is a brief guide to implementing controls at various stages of PCB operation.
laminated
Lamination is a dehydration step in PCB manufacturing. Because the core and prepreg are stacked together, the layers are glued into the laminate. The main factors controlled during the lamination process are temperature, elapsed time and heating rate. Sometimes when the dryness is low, take measures to reduce the vacuum to reduce the possibility of attracting internal voids absorbed by moisture. Therefore, the use of gloves when handling prepreg can control the degree of moisture. This reduces cross-contamination. Non-corrosive humidity indicator cards should be flexible so that humidity levels can be resolved when needed. Laminates should have a short wash cycle and be effectively stored in a controlled environment, which helps prevent moisture pockets from forming in the laminate.
Post lamination process and PCB assembly
After drilling, photo imaging and etching operations in PCB manufacturing, the moisture absorption rate captured in the wet process is higher. Screen printing curing and solder mask baking are processed steps to ease entrapped moisture. It is even more keen to manage storage conditions by minimizing the retention time interval between steps, which is more effective in reducing the level of moisture absorption. By ensuring the early stages of PCB lamination, the circuit board is sufficiently dry to help reduce baking operations after lamination. In addition, high-quality surface treatment is used to prevent cracks during the drilling process, and the humidity of the residue is removed by baking before the hot air solder leveling process. Baking time should be maintained by considering the determined level of moisture content, the complexity of PCB manufacturing, PCB surface treatment, and sufficient thickness required by the circuit board.
لذلك ، من المهم فهم أحدث حالة لتأثيرات الرطوبة في تصنيع ثنائي الفينيل متعدد الكلور. لتجنب الأعطال والتلف والدوائر القصيرة على PCB ، مع زيادة تكاليف إعادة العمل. الآن ، الباحثون على وشك تقديم حلول أكثر تقدمًا تستخدم تقنية ثنائي الفينيل متعدد الكلور الصديقة للبيئة للتحكم في عنصر الرطوبة في كل خطوة من خطوات تصنيع ثنائي الفينيل متعدد الكلور ، وبالتالي توفير الوقت والطاقة والتكلفة.