This is the final of three parts covering “resin infusion technology”, a composites processing
method that has continued to grow in popularity while at the same time encompassing a wide
variety of manufacturing versions for both aerospace and commercial markets. The January-
February 2007 issue of the SAMPE Journal focused in Part 1 on various industry highlights and
the time frame over which various supporting technologies entered into the resin infusion
processing technology growth. In the May-June 2007 issue, Part 2 covered a bit of the process
definitions and industry variations where RTM (resin transfer molding) and VIP (vacuum
infusion molding) are encountered. The distinction between the RTM (pressure feed) and VIP
(vacuum draw) processes were elaborated upon.

This particular discussion provides the interested reader with more detail on process advantages,
disadvantages, comparison of processes and details on significant parameters affecting the
process. Most of the tables are self explanatory so voluminous text discussion is not necessarily
warranted here. The interested reader is also provided with several key references at the end of
this part for future reading on the subject. Needless to say, SAMPE’s symposia and technical
conferences over the past 15 years or so have been filled with a very large number of technical
papers on the subject matter and the interested reader is certainly encouraged to look through any
of the SAMPE Proceedings (www.sampe.org). Subjects pertinent to the resin infusion
technology area will typically be: resin infusion, RTM, VARTM, VIP, SCRIMP, RFI, preforms,
textiles, infusion resins and flow media.

Table 1 highlights the various advantages and disadvantages of pressure-feed RTM processing.
There are some distinct differences in RTM processing for aerospace applications that are
different from commercial applications. The reference by Kruckenberg and Rowan is very good
in pointing out aerospace RTM processing steps and attributes.

Table 1. RTM-type process advantages and disadvantages.