Research On High Alumina Fly Ash Aetivating Flux And B-C-S Multi Elements Penetrating Of Tungsten Inert Gas Are Remelting Technology

In this paper,this dissertation concentrates studies of high alumina fly ash as main activating flux materials.The best basic composition of high alumina fly ash composite activating flux of Q235 steel is determined through uniform design experiment.The high alumina fly ash composite activating flux is composed by high alumina fly ash,SiO2,TiO2,Si and CeO2 with contents of 59.94%,31.90%,4.01%,1.42% and2.73%,respectively,and its ratio of depth to width is 3.31 times as that of high alumina fly activating flux under the same circumstance.The effect of welding parameters such as welding current and welding speed have been studied. The best welding current is 140A,and the best welding speed is 110mm/min.The method of powder pack comentation is used of B-C-S three element alloying layer on Q235 steel. Tungsten inert gas arc remelted layer is prepared on B-C-S three element alloying layer by tungsten inert gas arc remelting,above these work,the high alumina fly ash composite activating flux is used to prepare the activating flux tungsten inert gas arc remelted layer.The B-C-S three element alloying layer,TIG remelted layer and A-TIG remelted layer of the cross-sections,XRD analysis,microstructure and organization,micro-hardness and abrasive wear resistance and erosion wear resistance with different variations are tested.Results show that the two-stage heating method can obtaine 110 ～130μm of thickness of layer.The result of XRD indicates that better performance of Fe2B and Fe3C,and anti-friction phase of FeS. The microhardness of layer is 1022Hv.The result of XRD indicates that Fe3(C,B,S) is produced in TIG remelted layer and Fe3(C,B), Fe23B6, Fe3Si, Fe3Al were produced in A-TIG remelted layer.The remelted layers hardness are only 834Hv and 739Hv respectively,and the thickness of layers were more than 1000μm and 1600μm. In the test of adhesive wear of B-C-S three element alloying layer,TIG remelted layer and A-TIG remelted layer increase by 1.82～2.10 times,3.30～41 times and 3.67～5.56times respectively,which compared with the Q235 steel matrix.Under different conditions of dry friction,the friction factor reduce from 0.37-0.66 to 0.34～0.6,0.19～0.57and0.13～0.35 respectively,and under different conditions of oil friction,the friction factor reduce from 0.11～0.13 to 0.08～0.12,0.07～0.11and0.04～0.09 respectively.Their abrasive wear resistance can increase by 1.67times,2.69times and 6.27times respectively.In the test of corrosion resistance,different speed and concentration of water and sand wear resistance increase by 1.20～1.54times,1.55～1.92times andl.89～2.81times respectively.The salty resistance increase by2.19 times,2.58 times and 2.77times respectively.