鋳鉄の黒鉛化におよぼす焼鈍雰囲気の影響
スポンサーリンク
概要
- 論文の詳細を見る
From the viewpoint of protective atmosphere for heat treatment, the effects of annealing atmospheres on the primary and secondary graphitization in making black heart malleable cast iron were studied. Namely, the relations between the graphitizing process of cementite in ledeburite or pearlite structures and the annealing atmospheres were investigated by observing the graphitizing behaviour of several single atmospheres such as Ar, N_2, H_2 CO, CO_2, H_2O and CH_4, as well as some practical furnace atmospheres which contain hydrogen as a component such as the mixed gas of N_2-H_2 system, the charcoal gas generated by blowing wet air and the exothermic gas produced through partial burning of propane. Results obtained are as follows. When heated in the elemental gas which contains hydrogen such as H_2, H_2O or CH_4, atomic hydrogen penetrated quickly into the cast iron. In these atmospheres, the number of graphite particles formed was decreased and simultaneously the diffusion of carbon in austenite or ferrite matrix was lowered because the meta-stable cementite in Fe-C system was stabilized remarkably with dissolved hydrogen. In consequence, primary graphitizing was retarded and secondary graphitizing almost stopped. In the other annealing atmospheres the penetration into the cast iron was so sluggish that the difference from that in the argon atmosphere was not recognized. In every annealing atmosphere except hydrogen, the "bull's eyes" structure was formed by the furnace being cooled after primary graphitization was completed. However, it was found that free ferrite phase was not precipitated in the hydrogen atmosphere. It was observed that the degree of super cooling and the dilatic value at A_1 transformation became lower than in the other atmospheres. When heated in various practical furnace atmospheres, both primary and secondary graphitization were disturbed rapidly with rising hydrogen and water vapor contents. The particular preventive tendency of dissolved hydrogen was very remarkable at the secondary graphitizing stage.
- 社団法人日本鉄鋼協会の論文
- 1965-05-01
著者
関連論文
- プロパンの発熱型雰囲気と鉄の平衡関係
- オーステナイトステンレス鋼の分極下での水素脆化挙動と応力腐食割れの関連性について
- 18Cr-8Ni オーステナイト系ステンレス鋼の応力腐食割れにおよぼす腐食雰囲気中の酸素の影響について(性質関係)
- 245 オーステナイト・ステンレス鋼の分極下での水素の挙動と応力腐食割れの関連性について(腐食・表面処理・高張力鋼, 性質, 日本鉄鋼協会 第 78 回(秋季)講演大会)
- オーステナイト系ステンレス鋼の応力腐食挙動におよぼす水素の影響
- 217 18Cr-8Ni ステンレス鋼の応力腐食割れと溶存酸素の関係(薄板・腐食, 性質, 日本鉄鋼協会第 77 回(春季)講演大会講演)
- 77 ガス滲炭および光輝処理に関する基確的研究(日本鐵鋼協會第 50 回講演大会講演大要)
- 19 ガス滲炭に関する研究 : 滲炭層の深さと靱性の関係について(第 53 回講演大会講演大要)
- ガス滲炭に関する研究 : 市販耐熱鋼および電熱線材の各種雰囲気に対する耐侵食性について
- 25 鋼の材質におよぼす調節雰囲気の影響(第 52 回講演大会講演大要)
- 108 ガス滲炭に関する研究 : 耐熱鋼および電熱線材の耐侵蝕性について(第 51 回講演大会講演大要)
- 78 鉄鋼の光輝処理の実施化試験(日本鐵鋼協會第 50 回講演大会講演大要)
- ガス滲炭に関する研究-1-
- 鋳鉄の黒鉛化におよぼす焼鈍雰囲気の影響
- 白心可鍛鋳鉄用白銑のガス脱炭
- 125 黒心可鍛鋳鉄の黒鉛化におよぼす焼鈍雰囲気の影響(性質, 日本鉄鋼協会第 63 回(春季)講演大会講演大要)
- 98 プロパンの発熱的変成雰囲気による白心可鍛鋳鉄の脱炭について(熱処理, 第 59 回(春季)講演大会講演大要)