Study On The Transition Interface And Mechanical Property Of Structures Based On The CMT

In this paper,the natural high strength and toughness structure of shell is used for reference to do research on the transition interface of heterogeneous additive and its influence on the mechanical properties of shaped structure based on the CMT technology.ER130S-G is selected as hard material and ER316L as soft material.First of all,the forming process of single metal additive is studied.The process parameters suitable for CMT additive are obtained and the influence rules of different factors on the forming size are analyzed through three factors and three levels of orthogonal test.And the influence of different lapping ratio on the forming of additive is obtained and the experimental parameters are optimized through the experiment of single-layer and multi-channel lapping of different materials.After that,the multi-layer and multi-channel block of high-strength steel was printed out with good technology.The average hardness of high-strength steel made of CMT additive is 362HV,which is slightly improved at the interface of road and layer.The average value of tensile strength is 1126MPa and the average value of impact toughness is 50J/cm~2.The interface structure of stainless steel and high strength steel was designed and the influence of structure change on the interface structure and properties was studied.It is found that the hardness of the interface between high strength steel and stainless steel increases significantly up to 412.2HV and it is 16%higher than the average hardness of hard materials.For the lap joint structure,the tensile property increases with the decrease of the residual width of the soft material while the impact toughness is the opposite.For the lap joint structure,the impact toughness of the double-layer stainless steel sandwich is much higher than that of the one layer stainless steel sandwich,but its tensile strength is lower than that of the other For the"S"type lap structure.The impact toughness of the component with the smallest lap ratio of adjacent soft materials is the highest and the tensile strength is not much reduced.Finally,the complex shell like high-strength steel-316L is designed based on the optimization of different heterogeneous interface structure.The average value of tensile strength is about 862MPa,which is 23.4%lower than that of pure high-strength steel.The average value of impact toughness is about 121.25J/cm~2,which is 140%higher than that of pure high-strength steel impact toughness.