| Utilize laser cladding prepare ceramic compound in the coating in low-priced low carbon steel surface, can obtain high hardness, wear-resisting, anti-corrosion composite.Iron base B4C ceramic cladding layer on carbon steel is created by a 5kW continuous wave CO2 laser, choose different scanning pace, different scanning power and different proportion melt, cover material go on the test respectively. Adopt optical microscope, SEM and XRD to analyze that melts and covers organization shape looks and structure of cladding layer, Utilize micro-hardness appearance, wear and tear test machine, electrochemistry corrode system and launch scratch test appearance test that melt and cover one layer of micro- hardness, hard-wearing, corrosion-resistant performance and melting the combination intensity of cladding layer.The results of laser cladding iron base B4C ceramic show that:get the best layer want to selected parameter P=2500W, v=300mm/min, B4C content is 20%. Laser cladding cover iron base B4C ceramic compound organization of the layer analysis indicate, choose laser power, scan pace and B4C content three influence decisive factor that laser processed these compare separately, Find the increase with the laser power melts widely and melts dark and all increases, and with scanning the increase of the pace, melt and melt the wide trend that reduces after increasing deeply; Under different B4C content, layer cover to melt dark to appear change that make a reduction of after increasing with B4C increase of content layer, melt widely and present"N"type change.It melt cover close to alloy layer there aren't line the parts, melt cover layers of upper strata organize until tiny branch is the brilliant and equiaxed grain brilliant to make up.The laser cladding layer of phase and composition to analysis indicate: Cladding layer make up phaseγ-Fe, Fe3C, Fe2B and B4C, just the content of the looks is different to some extent mainly; The B4C ceramic particle not melted in cladding layer.Laser melt, cover iron pottery, B4C of base, compound performance of coating analysis indicate detailed to strengthen, not firm to dissolve strengthen and second phase enzyme person who strengthen comprehensive function while being brilliant, melt the hardness, wearability of covering layer and is able to bear corrosivity being all improved under different craft parameters.Have melted the micro-hardness (1212~1371HV0.2) of cladding layer and raised by 541~603% than the substate (195HV0.2) under the best craft parameter; The quality of average wearing (3.6×10-3g) and tearing is 16.8% of the substrate (22×10-3g), the wearability is improved by sixth times than the matrices; It is 23.81μA/cm2 to corrode the density of the electric current by oneself, than corroding the density of the electric current 50.49μA/cm2 small by oneself of steel matrices of lower carbon.Launch scratch test indicate under most big load function of 100N, cladding layer combine substrate well, there are no stripping and avalanche phenomenon.
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