(Fe)-C-N合金经沉淀硬化后的疲劳强度(英文)

Fatigue Strength of (Fe)-C-N Alloys After Precipitation Hardening

为了寻求新的方法促进渗氮工艺在重型机械零件中的应用 ,渗氮层的硬化及通过对基体和心部进行进一步奥氏体化并快冷使其硬化的可能性引起了注意。本文给出了渗氮后的 4 5钢 (C 0 .4 5 % ;Mn 0 .65 % )经沉淀硬化处理后的疲劳强度试验结果。试验结果表明经沉淀硬化后其近表层获得了不同的组织 ,可发现形态上与不同沉淀分散程度的贝氏体组织相似的纯马氏体区。渗氮后沉淀硬化有利于碳钢及其抗疲劳强度。

In search for new solutions promoting expansion of nitriding application to heavy duty machine parts there has been drawn attention to a possibility of hardening of a nitrided layer, of hardening of its substrate and its core through further austenitizing connected with fast cooling. In the paper, there were given results of fatigue strength tests carried out on nitrided 45 carbon steel (C-0.45%; Mn-0.65%) after precipitation hardening. It was found that the near-surface zone obtained different structure after precipitation hardening. There could be found pure martensitic areas, morphologically similar to bainitic structure of various levels of precipitate dispersion. Research showed that nitriding followed by precipitation hardening beneficially affect carbon steel and fatigue strength. Discussed here nitriding process followed by precipitation hardening could create an alternative for carburising or induction hardening.