ボロン処理した Cr-Mo-Nb 鋼の焼入性と高温焼もどし特性に及ぼす微量成分元素の影響

スポンサーリンク

概要

論文の詳細を見る
The hardenability and the properties after tempering at high temperature in boron treated Cr-Mo-Nb steels have been investigated with regard to the effect of microalloying elements. The results are as follows : (1) The hardenability and the toughness are divided roughly into three regions according to B and N contents under the condition that Ti and sol. Al contents are fixed. In the first region, dissolved B ([B]) content is poor, so steels have low hardenability. In the second region, [B] content is excess and steels have inferior toughness because of coarse M_<23>(C, B)_6 boro-carbides precipitation and denuded zones formation along grain boundaries on tempering treatment at high temperatures. In the third region, [B] content is optimum and steels have good hardenability and high toughness. The upper shelf energy, however, decreases when B is more than 30ppm. (2) Ti and sol. Al contents affect [B] content, and therefore the boundary lines above mentioned shift with the addition and reduction of Ti and/or sol. Al. (3) Grain boundary carbides are M_3C type carbides in B-free steels, and M_<23>(C, B)_6 type boro-carbides in B-treated steels. In the N stabilized steels, M_<23>(C, B)_6 precipitates are fine, if [B] is less than about 10ppm.
社団法人日本鉄鋼協会の論文
1986-07-01

著者

関連論文

もっと見る

スポンサーリンク