TGA2型熱(re)重(zhong)分(fen)析(xi)(xi)儀是(shi)一種(zhong)利用熱(re)重(zhong)法檢測(ce)物(wu)(wu)(wu)質(zhi)(zhi)(zhi)(zhi)溫(wen)度-質(zhi)(zhi)(zhi)(zhi)量(liang)(liang)變(bian)(bian)化關系的(de)儀器。熱(re)重(zhong)法是(shi)在程序控溫(wen)下(xia)，測(ce)量(liang)(liang)物(wu)(wu)(wu)質(zhi)(zhi)(zhi)(zhi)的(de)質(zhi)(zhi)(zhi)(zhi)量(liang)(liang)隨溫(wen)度（或(huo)時(shi)間）的(de)變(bian)(bian)化關系。當被測(ce)物(wu)(wu)(wu)質(zhi)(zhi)(zhi)(zhi)在加(jia)熱(re)過程中有升華(hua)、汽(qi)化、分(fen)解出氣(qi)體或(huo)失去結晶水時(shi)，被測(ce)的(de)物(wu)(wu)(wu)質(zhi)(zhi)(zhi)(zhi)質(zhi)(zhi)(zhi)(zhi)量(liang)(liang)就會發生變(bian)(bian)化。這時(shi)熱(re)重(zhong)曲線就不是(shi)直(zhi)線而是(shi)有所下(xia)降。通(tong)過分(fen)析(xi)(xi)熱(re)重(zhong)曲線，就可(ke)以知(zhi)道被測(ce)物(wu)(wu)(wu)質(zhi)(zhi)(zhi)(zhi)在多(duo)少(shao)(shao)度時(shi)產(chan)生變(bian)(bian)化，并且根據失重(zhong)量(liang)(liang)，可(ke)以計算失去了多(duo)少(shao)(shao)物(wu)(wu)(wu)質(zhi)(zhi)(zhi)(zhi)，（如CuSO4·5H2O中的(de)結晶水）。
