Research On Additive Manufacturing Process Of Plasma Arc With 316L Stainless Steel-High Nitrogen Steel Dissimilar Metal

This article was based on ABB plasma arc additive manufacturing robot equipment,316 L stainless steel and austenitic high-nitrogen stainless steel are used as the object to study the single-pass forming process parameters and the single-pass forming dimensions were analyzed and matched.The 316 L stainless steel-high nitrogen steel dissimilar metal multi-pass surface forming process includes the influence of track pitch,additive path and interlaced form on the surface forming flatness.On this basis,the interface and microstructure of dissimilar metal addition materials were further analyzed.The process of dissimilar metal plasma arc addition was studied.The interweaving structure of dissimilar stainless steel was designed and the mechanical properties of the molded parts were studied.First,a single-pass forming process experiment of 316 L stainless steel and austenitic high-nitrogen steel was carried out.The process parameters of stainless steel and high-nitrogen steel formed in a single pass were determined.The effects of additive speed and wire feed speed on the forming dimensions of single pass were analyzed by using well-formed process parameters,and the process parameters of dissimilar stainless steel single-pass molding were matched within the test range.The process parameters with the best dimensional matching are obtained within the selected parameters: stainless steel additive current 130 A,additive speed 1.7mm/s,wire feed speed 1.2 m/min;high nitrogen steel additive current 130 A,additive speed 1.9 Mm / s,wire feed speed 2.1m / min.Then,the multi-pass surface forming process of 316 L stainless steel-high nitrogen steel dissimilar metal was studied.Control other parameters unchanged,when the track spacing is5.1mm-5.5mm,the flatness K value is lower,the multi-channel surface flatness is the best;when the stainless steel and high-nitrogen steel track are interwoven,the ratio is 2:3 and 3:2When the surface is relatively flat,the surface flatness is higher when the additive path is stacked at an angle of 90° between the layers.Finally,the interfacial microstructure and mechanical properties of 316 L stainless steel-high nitrogen steel dissimilar metal multilayers were analyzed.The interlaced interface region was divided,and the EDS component analysis was carried out on the interface.The mechanism of the heterogeneous metal additive interface strengthening and toughening was analyzed from the perspective of the microstructure and alloying elements in different regions of the interlaced interface.The design of the interweaving structure was carried out,and the formation characteristics of 316 L stainless steel in the additive structure were analyzed fromthe solidification mode and the influence of thermal energy.The mechanical properties of the intertwined structural parts were analyzed.The test shows that with the increase of the additive height,the hardness of the same kind of additive structure decreases continuously,and the peak of the hardness appears at a certain interval of the interface;The hardness of the steel is reduced and the hardness of the 316 L stainless steel is increased.316 L stainless steel has better toughness than high-nitrogen steel,and also has better frontal impact resistance,while the impact resistance of high-nitrogen steel is rarely affected by the impact part;the sequential impact sequence will cause the interweaving structure.Different impact energy absorption effects;even if the interweaving structure has different material distributions,as long as they have the same ratio,they will have similar side impact energy absorption capability;they have similar positive and side impact resistance at complex interlaced parts,and the part The impact resistance is the biggest.