不同强度匹配10CrNi3MoV船体钢焊接结构的安全评定

为了研究不同强度匹配对焊接接头安全性能的影响,基于"欧洲工业结构完整性评定程序(SINTAP)"提供的失效评定图FAD方法,针对不同强度匹配的10CrNi3MoV船体钢焊接接头,建立了对应的失效评定曲线。根据母材与焊缝的拉伸试验及CTOD(裂纹尖端张开位移)试验结果,对比分析了3种匹配条件下的接头安全评定结果。研究表明,对于选定的评定级别,不同强度匹配系数对FAD图形状的影响很小;焊缝强度较高时,接头对塑性失稳的抵抗能力取决于母材性能;接头韧度水平相似时,低匹配接头对塑性失稳及脆性断裂的抵抗能力均稍差,弱于等匹配与高匹配;焊缝强度稍高于母材的"等强匹配"安全裕度最大,安全性最佳。

Safety assessment for welded structures of 10CrNi3MoV hull steel with different strength matching levels

In order to study the effect of strength matching level on safety performance of welded joint,with the application of ’failure assessment diagram’(FAD) approach provided by ’Structural Integrity Assessment Procedure for European Industry’(SINTAP),this paper set up failure assessment curves of 10CrNi3MoV steel joints with three different strength matching ratios.According to the tensile test and CTOD(Crack Tip Opening Displacement) test results,the joints were assessed.Through several comparative analyses,a few conclusions were derived.Under the conditions of different matching levels,FAD shapes of Classes 1 and 2 change little.When weld strength is higher,the joint’s resistance of the plastic instability mostly depends on the base metal properties.On the occasion that toughness of joints is similar,joint with under-matching weld behaves somewhat worse on the resistance to both plastic stability and brittle fracture.The ’even-matched’ joint with weld strength that is slightly higher than the base metal shows the best security performance.