Fatigue Behavior of Plasma-Assisted Duplex Surface-Treated Steels

等离子辅助双相表面处理钢的疲劳行为

• 批准号: 09650092
• 负责人: SHIOZAWA Kazuaki
• 金额: $ 2.18万
• 依托单位: Toyama University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 1998
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09650092/
• 关键词: Fatigue; Surface treatment; Duplex treatment; Nitriding; TiN; Topography; Subsurface crack; Steel; イオン窒化; TiN被覆; 鉄鋼; 腐食疲労; 残留応力; フィッシュ・アイ

Cantilever-type rotating-bending fatigue tests in air were conducted using smooth specimens of alloy tool steel, JIS SKD61, with three kinds of surface treatment ; namely, TIN coating by the PVD method, plasma-assisted ion-nitriding, and duplex treatment with plasma-nitriding followed by TiN coating. Fatigue strength of the surface-treated specimens was improved as compared with untreated specimens. The increase in the fatigue strength of the specimen by surface treatment was due to the transition of the fatigue-crack initiation site from the surface to the subsurface by an effect of the modified surface layer becoming barrier to the formation of surface crack nuclei beneath the TiN coating film. The difference in fatigue strength between the duplex surface-treated specimen and the plasma-nitriding one, for which the crack initiation site was subsurface, is discussed through the effect of the TiN coating film on subsurface crack growth behavior. The fracture surface was reconstructed by topographical data and a fracture process computationally simulated with fracture surface topography analysis. It was found that thc TiN coating film acts as a barrier to formation of a plastic zone at the front of a subsurface crack and retards crack growth toward the surface.

采用合金工具钢JIS SKD61、三种表面处理的光滑试样进行空气中悬臂式旋转弯曲疲劳试验；即PVD法镀TIN、等离子辅助离子渗氮、等离子渗氮后进行TiN镀层的双重处理。与未处理的样品相比，经过表面处理的样品的疲劳强度有所提高。通过表面处理提高样品的疲劳强度是由于改性表面层成为 TiN 涂层膜下表面裂纹核形成的屏障，从而使疲劳裂纹萌生位置从表面过渡到表面下。通过 TiN 涂层膜对次表面裂纹扩展行为的影响，讨论了双相表面处理样品与裂纹萌生位置位于次表面的等离子渗氮样品之间疲劳强度的差异。通过形貌数据重建断裂表面，并通过断裂表面形貌分析计算模拟断裂过程。研究发现，TiN 涂层膜可作为在表面下裂纹前端形成塑性区的屏障，并阻止裂纹向表面扩展。

项目成果

K. Shiozawa: "Some affecting factors for Fatigue strength of ceramics coating steel" Surface Treatment. 227-236 (1997)

K. Shiozawa：“陶瓷涂层钢疲劳强度的一些影响因素”表面处理。

塩澤和章: "プラズマ光輝窒化とTiN被覆のハイブリッド表面改質処理を施したSKD61鋼の疲労強度特性" 日本材料学会第46期学術講演会講演論文集. 273-274 (1997)

Kazuaki Shiozawa：“等离子光亮氮化和TiN涂层混合表面改性处理的SKD61钢的疲劳强度性能”日本材料学会第46届学术会议论文集273-274（1997）。

K.SHIOZAWA: "Some Affecting Factors for Fatigue Strength of Ceramics Coating Steel" Surface Treatment-Computer Method and Experimentsl Measurement, pp227-236, Eds.by M.H.Aliabadi and C.A.Brebbia, Comp.Mech.Pub., Southampton. (1997)

K.SHIOZAWA：“陶瓷涂层钢疲劳强度的一些影响因素”表面处理-计算机方法和实验测量，第 227-236 页，M.H.Aliabadi 和 C.A.Brebbia 编辑，Comp.Mech.Pub.，南安普敦。

塩澤和章: "複合表面改質を施したSCM440鋼の耐食性と腐食疲労強度特性" 日本機械学会 講演論文集. 98-5B. 59-60 (1998)

Kazuaki Shiozawa：“复合表面改性的 SCM440 钢的耐腐蚀性和腐蚀疲劳强度特性”日本机械工程师学会会议记录 98-5B（1998）。

塩澤和章: "プラズマ利用複合表面処理鋼(SKD61)の疲労強度と内部き裂進展特性" 日本機械学会論文集, A編. 64・628. 3050-3057 (1998)

Kazuaki Shiozawa：“基于等离子体的复合材料表面处理钢（SKD61）的疲劳强度和内部裂纹扩展特性”，日本机械工程师学会会刊，A版64・628（1998年）。