Silicone potting sealant is commonly used as heat conduction, heat dissipation, sealing, and seismic materials in electronic components. Heat conduction sealing refers to the pasting of all components on the PCB circuit board so that the heat generated on the components of the PCB can quickly spread to the external thermal conductive substrate (aluminum or thermal ceramics, etc.) through the heat conduction sealing glue, and finally directly transferred to the external environment.
Electronic potting glue will encounter a variety of problems in the construction, after all, electronic potting glue belongs to chemicals, in the construction by temperature, water vapor and operation process and other reasons, resulting in a lot of problems. Understanding these reasons will help to smooth the construction and avoid rework.
Operation tools: acetone, toothbrush, washbasin, rag, toilet paper. Operation steps:
The important properties of adhesives include rheological properties (viscosity, thixotropy, collapse-resistance and tail-dragging, storage life/condition and effective life) and mechanical properties (viscosity, mechanical strength and heat resistance, curing period, electrical stability, etc.)
Electronic adhesives for microelectronic packaging can be divided into semiconductor IC packaging adhesives and PCB board-level assembly adhesives according to packaging forms. The semiconductor IC encapsulating Adhesives are EMC, LED Encapsulant, Die Attach wrapping Adhesives, Flip Chip Underfills, Dam and Fill Encapsulant. Adhesives for PCB board assembly are SMT Adhesives, COB Encapsulant, FPC Reinforcement Adhesives, CSP/BGA Underfills, Image Sensor Assembly Adhesives, conformal coating, Encapsulant, Encapsulant, Encapsulant, Thermal conductive adhesive (Thermally conductive adhesive).
The cause of the problem: the catalyst in the glue is toxic or expired; Insufficient curing temperature or time caused by incomplete curing. The cause of the problem may be: because of measuring instrument error or human factors caused by the proportion of glue error; Failure occurs when the product exceeds or is close to the shelf-life; Reduced efficiency; Failure of catalyst in product or reduction of efficiency due to improper storage during storage; The catalyst may be toxic in the environment when used, such as phosphorus, sulfur, and nitrogen
