We made a 3D printing of 960 high-strength steel thin-walled components using direct current and pulsed current wire arc additive manufacturing and conducted the research on thermal process,microstructure and mechanical properties of thin-walled components during wire arc additive manufacturing of 960 high-strength steel,which provides useful reference for the engineering application of Pulsed-TIG(PTIG)technology. The results indicated that both the direct current deposition and the pulsed current one are really stable,and have reliable precision. The height to width ratio of pulse current deposition component is relatively low and the deposition layer becomes more flatter after pulse is added, which is beneficial to keep the molten pool stable during deposition and improve the forming accuracy. The microstructure distribution of the sedimentary layer from bottom to top is not uniform. The bottom layer is composed of fine austenite grains,the middle layer is coarse equiaxed grains,and the top layer is composed of austenite and partially tempered martensite. Through the introduction of pulse,the structure uniformity and temper martensite structure formation are effectively improved,and the plasticity and toughness of the material are improved. Direct current TIG-wire arc additive manufacturing(TIG-WAAM)and pulse current TIG-wire arc additive manufacturing(PTIG-WAAM)droplet transition modes were large droplet transition and fine droplet transition,respectively,and the transition frequencies were 5. 24 Hz and 9. 17 Hz,respectively. The high-frequency transition mode of droplets under pulse current is more beneficial to ensure the thermal stability,forming accuracy and process stability of the whole deposition process. © 2023 Cailiao Daobaoshe/ Materials Review. All rights reserved.
