Silica gel preparation method

Abstract

The invention provides a silica gel preparation method which comprises the following steps of: respectively placing more than two aged raw material components for preparing silica gel in barrels of a stirring mechanism, maintaining in the vacuum state and respectively intermittently stirring the raw material components of the silica gel for foam discharging; arranging discharging holes in the barrels, communicating with transporting pipelines through transporting pumps, connecting the transporting pipelines with filling and sealing openings of the raw material components, arranging reflow pipelines capable of being closed between the filling and sealing openings and the transporting pumps, and sending the raw material components subjected to the foam discharging into respective transporting pipelines; and closing the filling and sealing openings of the transporting pipelines, and enabling the raw material components to return to the barrels through reflow pipelines to form reflow, and controlling the reflow states of the materials until the whole transporting pipelines of all components are in the vacuum state. The preparation method meets the requirements of an IGBT (Insulated Gate Bipolar Transistor) module for consistency and reliability of products produced massively and in batches.

Description

technical field [0001] The invention relates to a material preparation process before encapsulation of electronic products, in particular to a silicon gel material preparation method suitable for the encapsulation process of IGBT modules with silicon gel. Background technique [0002] With the rapid development of China's economy, high-speed rail, subway, urban rail transit, wind power, solar energy, clean energy and other fields are constantly developing. In these fields, IGBT modules are widely used in some inverter devices in these fields. With the development of science and technology, the high-tech content and complex structure of the converter device has a strong specialization and tends to be more modular. The production of such large-scale modular components places extremely high demands on IGBT modules in terms of product consistency and reliability. IGBT (Insulated Gate Bipolar Transistor) is a device composed of MOSFET and bipolar transistor. In the production of...

AI Technical Summary

Problems solved by technology

[0006] In the production of potting and sealing, the silicone gel prepared according to the above method is generally used for potting in a ready-to-use way. On the one hand, the components of the silicone gel have been mixed and stirred evenly in the preparation before potting Finally, vacuum defoaming treatment is carried out. During this process, the components of the silicone gel will undergo a certain degree of chemical cross-linking reaction to form a network structure. Such preparations are used for potting, which will make each batch of products The preparation of silicone gel materials is different, so it is easy to cause a big difference in the electrical performance of the IGBT modules after different batches of preparation and potting, which cannot meet the consistency requirements of IGBT module products. If it is too long and changes, it is actually necessary to prepare materials as they are used, which will also affect the efficiency of industrial batch production; on the other hand, in the traditional silicone gel preparation, after mixing and stirring the components Carry out vacuum defoaming treatment, during this process, the components of the silicone gel will undergo a certain degree of chemical crosslinking reaction to form a network structure; the traditional method of preparing silicone gel materials is only after the components of the raw material are mixed and stirred evenly Vacuumizing and defoaming treatment does not require how to transfer the prepared materials to the potting port and perform potting, and it is impossible to transfer the silicone gel in a vacuum state, and it is still inevitable to bring air bubbles into the potting port

Therefore, it is difficult to meet the requirements of consistent performance indicators, good repeatability, and reliable quality of large-volume products when using traditional material preparation methods for large-scale and standardized production.

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