"挥发组分含量" can be translated into English as "volatile component content" or "volatile matter content".
"Volatile component" specifically refers to the part of a substance that can vaporize easily, while "content" denotes the proportion or amount of something within a whole.
"Volatile matter" is another common term used in some technical or industrial contexts to describe substances that can readily change into vapor.
Both expressions are accurate and can be used depending on the specific context and audience.