单面焊接接头的断裂特性研究

Research on the Fracture Characteristics of One-side Welding Joints

采用拉伸试验研究了１６Ｍｎ钢陶质衬垫手工单面焊接接头强度、塑性，应力－应变关系特性．同时使用扫描电镜、能谱分析仪观察了拉伸断口形貌，测定了夹杂物的成分、分布特征以及常温下接头的临界空穴扩张比Ｒ_ｃ／Ｒ_ｏ，讨论了Ｒ_ｃ／Ｒ_ｏ的分布规律和接头的断裂韧性．

The paper researches the strength, plasticity and the stress-strain relationship of oneside welding joints of 16Mn steel with shielded metal arc welding and ceramic backing. By observing the appearance of fracture zone,measuring the impurity composition and distribution and the critical void-growth ratio of the joints at normal temperature under scanning electron microscope,it discusses the distribution regulation of the critical zoid-growth ratio and fracture toughness of the joints and concludes that the effects of ceramic backing on the static strength and plasticity are relatively small,but on the chemical composition of deposited metal and the fracture behavior are relative large,and the critical void-growth ratio is obedient to normal distribution. Furthemore,the reasons of the obvious difference between the measuring and predicting the critical void-growth ratios are analyzed in this paper.