raw material is what we are badly in need of.能换成Raw material

不可以.
sb be in need of sth 是“某人需要某物”的意思,固定短语.这里的need是名词,介词of是不可缺少的,what做of的宾语.系动词be后还可以用副词badly修饰,或者need前面用形容词great修饰,以加重语气.如：We are in need of money.“我们需要钱.”After the earthquake,the victims were badly in need of help.“地震后,灾民急需救助.”Many countries are in great need of oil.“许多国家急需石油.”
当然,我们还可以把楼主的句子说得更简单,即Raw material is what we (badly) need .这时,need就成了我们常见的及物动词了.