To investigate the effect of the arc re-melting on the microstructure,mechanical and tribological properties of the 390 A alloy,its ingot produced by the conventional induction melting method was subjected to the arc ...To investigate the effect of the arc re-melting on the microstructure,mechanical and tribological properties of the 390 A alloy,its ingot produced by the conventional induction melting method was subjected to the arc re-melting process.The microstructure of the 390 A alloy was examined by OM and SEM.Mechanical properties of the 390 A alloy were determined by the Brinell method and tensile tests.Tribological properties were investigated with a ball-on-disc type tester.It was observed that the microstructure of both conventional induction melted and arc re-melted 390 A alloys consisted ofα(Al),eutectic Al-12 Si,primary silicon particles,θ-CuAl_(2),β-Al_(5) FeSi,δ-Al_(4) FeSi_(2),andα-Al_(15)(FeMnCu)3 Si_(2) phases.Re-melting with the arc process caused grain refinement in these phases.In addition,after this process,theα(Al)phase and primary silicon particles were dispersed more uniformly,and sharp edges of primary silicon particles became round.The arc re-melting process resulted in an increase in the hardness of the 390 A alloy produced by the conventional method from 102 HB to 118 HB and the tensile strength from 130 to 240 MPa.It also caused an increase in the wear resistance of the 390 A alloy and a decrease in the friction coefficient.展开更多
文摘To investigate the effect of the arc re-melting on the microstructure,mechanical and tribological properties of the 390 A alloy,its ingot produced by the conventional induction melting method was subjected to the arc re-melting process.The microstructure of the 390 A alloy was examined by OM and SEM.Mechanical properties of the 390 A alloy were determined by the Brinell method and tensile tests.Tribological properties were investigated with a ball-on-disc type tester.It was observed that the microstructure of both conventional induction melted and arc re-melted 390 A alloys consisted ofα(Al),eutectic Al-12 Si,primary silicon particles,θ-CuAl_(2),β-Al_(5) FeSi,δ-Al_(4) FeSi_(2),andα-Al_(15)(FeMnCu)3 Si_(2) phases.Re-melting with the arc process caused grain refinement in these phases.In addition,after this process,theα(Al)phase and primary silicon particles were dispersed more uniformly,and sharp edges of primary silicon particles became round.The arc re-melting process resulted in an increase in the hardness of the 390 A alloy produced by the conventional method from 102 HB to 118 HB and the tensile strength from 130 to 240 MPa.It also caused an increase in the wear resistance of the 390 A alloy and a decrease in the friction coefficient.
