Microstructure and Hardness Distribution of Ductile Iron by PTA Cr-Ni-Mo-Cu Alloying

Hua Tang Cao; Xuan Pu Dong; Qi Wen Huang; Zhang Pan; Jian Jun Li; Zi Tian Fan

doi:10.4028/www.scientific.net/AMR.852.188

Paper Titles

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Interface Microstructure and Properties of 304 Austenite Stainless Steel/Low Carbon Steel Clad Plate by Casting and Hot Rolling Process
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Thermodynamic Optimization Design of Casting Mg-Zn-Cu Alloy
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Microstructure and Hardness Distribution of Ductile Iron by PTA Cr-Ni-Mo-Cu Alloying
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First-Principle Study of Atomic Structures of Fe/TMC (TM=Ti, Zr and Hf) Interface
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First-Principles Study of the Mechanical Properties of ScAl Microalloyed by 4d-Transition Metals
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Influence of the Electric Current Pulse with Different Pulse Width on the Eutectoid Microstructure of Hypoeutectic Fe-C Alloys
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HomeAdvanced Materials ResearchAdvanced Materials Research Vol. 852Microstructure and Hardness Distribution of...

Microstructure and Hardness Distribution of Ductile Iron by PTA Cr-Ni-Mo-Cu Alloying

Abstract:

The mixture powder of Cr, Ni, Mo and Cu were deposited evenly on a ductile iron with ferrite matrix and treated by plasma transferred arc (PTA). The microstructure and hardness distribution of the PTA-alloyed layers were investigated by using scanning electron microscope (SEM) equipped with energy dispersive spectroscopy (EDS), X-ray diffraction (XRD) and microhardness tester, respectively. Results show that the cross-section consists of four regions: alloyed zone, melted zone, heat affected zone and unaffected substrate. The maximum microhardness of PTA-alloyed sample is measured to be as high as 1077 HV_0.2, which is approximately 4.4 times higher than that of substrate. The improvement is attributed to the formation of mixed hard-phases such as Cr₇C₃, C₂₃C₆, martensite, cementite under nonequilibrium solidification, and the solution strengthening by the alloying elements as well as grain refining via the rapid cooling.