20th European Conference on Fracture (ECF20) Fatigue strength of welded ultra high strength steels improved by high frequency hammer peening
20th European Conference on Fracture (ECF20) Fatigue strength of welded ultra high strength steels improved by high frequency hammer peening
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第 20 届欧洲断裂会议 (ECF20) 通过高频锤喷提高焊接超高强度钢的疲劳强度
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发表时间：
2014
期刊：
影响因子：
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通讯作者：
N. Stranghoener
中科院分区：
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作者：
Joern Berg;N. Stranghoener
高频锤击（HFHP）对疲劳强度影响的现有设计建议仅限于S960的最大钢强度和5 mm及以上的板厚度。HFHP对屈服强度为960 N/mm 2及更高的焊接超高强度钢在有限疲劳寿命区低周疲劳（LCF）载荷下的疲劳强度的影响迄今尚未得到充分研究。因此，杜伊斯堡-埃森大学金属和轻型结构研究所对四种不同的焊接细节进行了疲劳试验，a）对接焊，B）横向加劲肋，c）纵向加劲肋和d）超高强度钢S960、S1100和S1300制成的盖板，以确定HFHP对疲劳强度的影响。HFHP处理试样的疲劳强度至少是焊趾状态下疲劳强度的两倍。与强度为S960和更低的钢的现有研究相比，HFHP处理试样的疲劳试验结果显示出相同的趋势：S-N曲线的斜率增加到approxim = 5。此外，在HFHP处理后，在某些情况下，裂纹萌生的位置从焊趾变为焊根或基体材料中的缺口。
Existing design recommendations for the influence of high frequency hammer peening (HFHP) on the fatigue strength are limited to maximum steel strengths of S960 and plate thicknesses of 5 mm and higher. The influence of HFHP on the fatigue strength of welded ultra high strength steels with yield strengths of 960 N/mm 2 and higher - loaded in low cycle fatigue (LCF) respectively uppe r finite fatigue life region - has not been investigated sufficiently so far. For this reason, the Institute for Metal and L ightweight Structures of the University of Duisburg-Essen has performed fatigue tests on four different welded details a) butt w eld, b) transversal stiffener, c) longitudinal stiffener and d) cover plates made of ultra high strength steels S960, S1100 and S1300 to determine the influence of HFHP on the fatigue strength. The fatigue strength of HFHP treated specimens was at least twice the fatigue strength of the as welded toe condition. In comparison with existing investigations for steel strengths S960 and lo wer, the results of the fatigue tests at HFHP-treated specimens showed the same trend: the slope of the S-N-curve increases to ap proximately m = 5. Furthermore, after HFHP treatment in some cases the location of crack initiation changes from the weld toe to the weld root or to notches in the base material.