酸性环境下粘接剂对异质压印接头剥离强度的影响

Effect of adhesive on peel strength of heterogeneous clinched joints under acidic environment

为探究酸性环境下粘接剂对异质压印接头剥离强度的影响,以热轧双相钢DP590和AA5052作为原材料,以0.02 mol·L^(-1)的NaHSO_(3)溶液作为腐蚀液,对异质压印接头(压印接头)和粘接-压印接头(粘-压复合接头)进行了干湿周浸交替腐蚀试验,通过静力学试验、微观失效断口以及能谱分析研究了接头在酸性环境下的静力学性能和失效机理。结果表明:粘接剂的使用显著提高了接头的最大失效载荷,粘-压复合接头的承载能力较压印接头提高了56.3%。粘接剂的使用对接头的失效形式未产生影响,在腐蚀时间为0 h时,压印接头和粘-压复合接头的失效形式均为内锁拉脱失效,但随着腐蚀的进行,失效形式逐渐转变为颈部断裂失效。粘-压复合接头上板的微观断口形貌均表现为韧窝状,下板拉伸失效部位的划痕逐渐加深。酸性腐蚀环境下压印接头搭接区域表面元素特征较粘-压复合接头变化明显,表明粘接剂的使用对压印接头起到了一定的保护作用。

To explore the effects of adhesive on peel strength of heterogeneous clinched joints under acidic environment,taking the hot-rolled dual-phase steel DP590 and AA5052 as the raw materials,and 0.02 mol·L^(-1) NaHSO_(3) solution as the corrosion solution,the heterogeneous clinched joints(clinched joints)and bonding-clinched joints(clinch-bonded hybrid joints)were subjected to wet-dry cyclic immersion alternate corrosion experiments.The static properties and failure mechanism of the joints under acidic environment were studied by static experiments,micro-failure fracture and energy spectrum analysis.The results show that the maximum failure load of the joints are significantly increased by using adhesive,and the bearing capacity of the clinch-bonded hybrid joints are 56.3%higher than that of the clinched joints.The use of the adhesive has no effect on the failure mode of the joints.When the corrosion time is 0 h,the failure modes of both clinched joints and clinch-bonded hybrid joints are internal lock pulling-out failure,but with the progress of corrosion,the failure mode gradually changes to neck fracture failure.The microscopic fracture morphologies of the upper plate of the clinch-bonded joints are characterized by dimples,and the slip marks at the tensile failure site of the lower plate gradually deepen.The surface element characteristics of the overlap area of the clinched joints under acid corrosion environment are more obvious than that of the clinch-bonded hybrid joints,indicating that the use of the adhesive has a certain protective effect on the clinched joints.