Strength of continuous fiber type CFRTP is large, however formability is restricted. On the contrary, discontinuous fiber type CFRTP is vice versa. Authors tried to obtain better balance between strength and formability by following process. (1) To induce fine cut group to CFRTP woven fabric prepreg sheet. (2) Sheets of prepreg were layered and consolidated to panel. Fine cut group was induced by fiber laser. Cutting condition was selected so as not to as much as possible to cause heat affected zone. Then GFRTP prepreg sheet was added on both surface to improve strength. Tested materials were TPS and PA66 matrix CFRTP. Formability test and strength test was conducted. Hemispherical shape forming test was conducted as formability test. Results were as follows. 1) Formability was improved by inducing fine cut group, especially panel in which both 0/90 °layer and ±45°layer were mixed could be formed. Strength of panel with fine cut group was about half of the panel without fine cut group. This value was sufficiently strong compared with the CFRTP panel of discontinuous fiber. 2) Adding GFRTP prepreg sheet to CFRTP panel with fine cut group on both surface did not restrict formability, but showed better effect to forming products. 3) Fracture load of panel by adding GFRTP prepreg sheet showed large increase. The amount of increase was much larger than the added strength of GFRTP.
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