VaRTM 공정을 이용한 복합재료 성형 시 이물질에 의한 Void 형성에 관한 연구

Abstract

In these days, composite materials are used overall industries such as in air crafts, ship construction, other marine industries, wind turbine blade, etc.

There are numerous process for fabricating of the composite materials for example Hand Lay-up / Spray-up, RTM(Resin Transfer Molding), VaRTM(Vacuum-assisted Resin Transfer Molding), Autoclave, etc.

Comparing to different process, the VaRTM(Vacuum-assisted Resin Transfer Molding) has many advantages above all other process.

The VaRTM process is widely used for manufacturing of large structures and the same process mostly offers high quality application similar to the autoclave process and it also have a cost advantage like hand lay-up process.

However, deposition of impurities during the VaRTM process make internal voids and these voids degrade mechanical properties of materials.

This documentation has been developed upon investigation on the voids which generated by deposition of impurities during the VaRTM process. It also includes deficiencies of composite materials for the voids generated during this process.

Impurities are intentionally inserted into the laminate for investigation, and NDI and optical observation are carried out.

Internal voids are generated on specimens with thick impurity. Void generation is occurred between the thickness of 1.6 ~ 4.0mm. And void growth is occurred between the thickness of 3.2 ~ 4.0mm. The diameter of void is proportional to the thickness of the impurity.

This study shows some useful data and relations between voids and impurities. Accordingly, the result of this paper could be used for improving a further quality of composite materials produced by VaRTM process.