Is Glass content(%) = Fiber volume fraction (Vf)?

[Laminator]

I read an article which stated that "Glass content: 40%". Does it mean that the fiber volume fraction (Vf) of that material is 0.4? or it means weight fraction (wf)?

Thanks.

 

[Compositepro]

It could mean either one, but would more probably mean weight percent. You could probably determine it from the context it was used in the article.

 

[Hansmeister]

Fiber content is typically given as "fiber volume". Resin content is typically given as "by weight".