Fatigue and Corrosion Fatigue Behaviour of Brazed Stainless Steel Joints AISI 304L/BAu-4 in Synthetic Exhaust Gas Condensate
Fatigue and Corrosion Fatigue Behaviour of Brazed Stainless Steel Joints AISI 304L/BAu-4 in Synthetic Exhaust Gas Condensate
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DOI：
10.3390/ma12071040
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发表时间：
2019-03
期刊：
影响因子：
3.4
通讯作者：
Anke Schmiedt-Kalenborn;L. Lingnau;M. Manka;W. Tillmann;F. Walther
中科院分区：
文献类型：
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作者：
Anke Schmiedt-Kalenborn;L. Lingnau;M. Manka;W. Tillmann;F. Walther
由于使用中的钎焊不锈钢部件通常必须承受腐蚀环境中的循环载荷，因此必须对钎焊接头的腐蚀疲劳性能进行表征。在腐蚀性介质中的应用相关的腐蚀疲劳试验是非常罕见的钎焊接头和循环变形曲线几乎没有研究。在本研究中，根据VDA 230-214，在空气和合成废气冷凝物K2.2中对钎焊AISI 304 L/BAu-4接头进行疲劳试验。将钎焊接头的疲劳行为与奥氏体基体材料的性能进行比较。应变、电、磁、温度和电化学测量技术应用于疲劳和腐蚀疲劳试验中，以确定钎焊接头的循环变形和损伤行为。结果表明，在2 × 106次循环下397 MPa的疲劳强度由于腐蚀载荷的叠加而降低到51%。不同的微观结构相关的损伤机制被确定为腐蚀疲劳载荷和疲劳载荷的试样在接收和预腐蚀条件。研究表明，腐蚀环境对钎焊不锈钢接头的机械性能的重要作用。
As brazed stainless steel components in service often have to withstand cyclic loads in corrosive environments, the corrosion fatigue properties of brazed joints have to be characterised. Application-relevant corrosion fatigue tests in corrosive media are extremely rare for brazed joints and cyclic deformation curves are barely investigated. In this study, fatigue tests of brazed AISI 304L/BAu-4 joints were performed in air and synthetic exhaust gas condensate K2.2 according to VDA 230-214. The fatigue behaviour of the brazed joints was compared to properties of the austenitic base material. Strain, electrical, magnetic, temperature and electrochemical measurement techniques were applied within fatigue and corrosion fatigue tests to characterise the cyclic deformation and damage behaviour of the brazed joints. It was found that the fatigue strength of 397 MPa at 2 × 106 cycles was reduced down to 51% due to the superimposed corrosive loading. Divergent microstructure-related damage mechanisms were identified for corrosion fatigue loadings and fatigue loadings of specimens in the as-received and pre-corroded conditions. The investigations demonstrate the important role of corrosive environments for the mechanical performance of brazed stainless steel joints.