This paper has investigated the influence of alloying element Nb on structure and properties of the soft nitriding layer by means of experiments of the matrix steels containing Nb and Nbfree.是什么意思_This paper has investigated the influence of alloying element Nb on structure and properties of the soft nitriding layer by means of experiments of the matrix steels containing Nb and Nbfree.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句