Surface irregularity and fatigue strength of mild and weathering steels exposed in corrosive environment for many years.
Surface irregularity and fatigue strength of mild and weathering steels exposed in corrosive environment for many years.
复制标题
多年暴露在腐蚀环境中的低碳钢和耐候钢的表面不规则性和疲劳强度。
DOI：
10.2472/jsms.37.434
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发表时间：
1988
期刊：
影响因子：
--
通讯作者：
O. Minata
中科院分区：
文献类型：
--
作者：
A. Nishimura;O. Minata
为了研究腐蚀钢板的疲劳性能，对低碳钢JIS SS 41和耐候钢JIS SMA 50分别进行了7年的材料试验和25年的海试疲劳试验，并对腐蚀钢板的表面粗糙度进行了分析。结果表明：（1）腐蚀钢板在表面粗糙度y/ymax≥0.56，（n/L）max≤1.2的条件下发生疲劳开裂。(2)耐候钢和低碳钢腐蚀坑边缘的平均角度分别为151°30′00″和156°49′54″。(3)根据腐蚀坑截面积计算的疲劳强度与疲劳试验结果基本吻合。(4)对于耐候钢，锈态表面2×106次应力循环的疲劳强度高于除锈后的疲劳强度。经2×106次应力循环后，除锈后的低碳钢的疲劳强度与未除锈的低碳钢相当。这可能是由于耐候钢表面的锈层具有消除应力和隔绝金属与大气的作用。
In order to investigate the fatigue behavior of corroded steel plates, fatigue tests and surface roughness analysis of the plates were carried out for two kinds of steel: mild steel JIS SS41 and weathering steel JIS SMA50 which were exposed for 7 years at a materialyard or for 25 years at seaside, respectively. The following results were obtained:(1) Fatigue cracking of the corroded steel plates occurred under the conditions of surface roughness with y/ymax≥0.56 and (n/L)max≤1.2.(2) The average angles at the fringe of corrosion pits were 151°30′00″ and 156°49′54″ for the weathering steel and mild steel, respectively.(3) The fatigue strengths calculated basing on the sectional area through corrosion pits nearly coincided with the fatigue test results.(4) In the case of weathering steel, the fatigue strength of the as-rusted surface for 2×106 stress cycles was higher than that of the rust removed surface. On the other hand, the fatigue strength of the rust removed mild steel for 2×106 stress cycles was nearly equal to that of the as-rusted mild steel. This fact may be caused by the adherent rust on weathering steel surface which has an effect of stress relief and cutting off the groundmetal from atmosphere.