Processing and characterization of SS316 based metal matrix composite casting through microwave hybrid heating

Abstract

In the current study, metal matrix composites of iron-based alloy (SS316) are successfully cast by the application of a novel processing route of microwave hybrid heating (MHH). The castings of iron-base alloy (SS316) powder and reinforced with 10 wt.% EWAC1004 (Ni-based) + 3 wt.% WC-12Co are developed in the domestic microwave oven power of 900 W and frequency 2.45 GHz. The mechanical and metallurgical properties of the prepared casts are investigated. The value of the mean particle size of the powder used is found to be 40 μm. Scanning electron microscopy (SEM), optical microscopy (OM), X-Ray diffraction (XRD), and Vickers’s microhardness tester are used for the characterization of so developed composites samples. The microstructure is reported as elongated columnar grains or lathlike structure with uniform melting of the iron-based (SS316) matrix has been achieved. The XRD confirmed the presence of typical carbides and intermetallic. The average micro-hardness of the reinforced composites is reported as 420 ± 90 HV0.3. The achieved microhardness of cast samples is 2 times the commercially received SS316. The micro-hardness obtained on the surface of the carbide phase is 648.16 HV0.3. The porosity of the prepared cast is found to be less than 2% which is approximately 3 times less as compared to commercially received SS316. The relative density of the microwave cast SS316 without reinforcement is found to be maximum with the value of 98%. The value of grain size of the microwave-casted composite samples is reduced to 23 microns (μm)

Influence of tungsten carbide-cobalt reinforcement on flexural behavior of iron-based composite developed through microwave

“…The average microhardness for 15%WC212Co reinforcement had 681. 23 6 253.94 HV claimed in this study due to the high inheritance of high hardness (2600 HV) 22 of tungsten carbide cobalt. Kaushal et al investigated the Metal matrix composite (MMC) clad of Ni + 10% WC8Co + Cr 3 C 2 on SS-316 L and claimed the microhardness of 550 6 35 HV.…”

“…The stress-strain curve Figure 12(c) showed a zig-zag profile because every composition percentage of powders materials interacts uniquely with the microwave during coupling. The low skin depth, improper mixing due to difference in density 7.9 g/cm 3 for SS316, and 8.9 g/cm 3 for EWAC (Ni-based), and also a difference in melting point 1371°C-1400°C for SS316 and 1455°C for EWAC(Ni-based), 22 of each powder the some of the nickel particles might be in semi-molten stage, which contributed for weakness in strength and pulled out at some points during flexural strength testing, while on the other hand, the properly melted nickel particles improve the flexural strength. Different responses of semi-molten and molten nickel particles in SS316+15EWAC gave a zig-zag trend, as shown in Figure 12(c).…”

“…13 used an electric stir casting furnace to prepare AA6061-T6 AMC with 15%-20% of Si 3 N 4 . The wettability increased by the addition of 2% of Mg in the charge, the hardness of 98VHN and 91BHN was observed, and the UTM increased from 159.82 MPa 22 49.12 MPa with 20% Si 3 N 4 . 14 Pakdel et al used spark plasma sintering (SPS) to develop AMMC with 1-10% WC micro, nano, and bimodal particles, the densification 99.8% and 94.4% obtained in microcomposites at 1 wt%WC and 10 wt.% nanocomposites respectively, but the nano-composites revealed largest microhardness value.…”

“…The complete mechanism of MHH has already been explained by Pal et al and other researchers. [22][23][24][25][26] A few minutes of exposure time, low cost, homogeneous and volumetric heating with a lesser thermal gradient in the processed materials are the significant features of MHH. Also, grain growth, improved morphology, lesser pores, and enhanced microhardness make it a more competitive manufacturing process than the abovementioned processes.…”

Development of iron-based composite materials through electromagnetic radiations in a domestic microwave oven

“…The literature shows that various parameters like preheating time and temperature of raw powders, microwave power, microwave processing time, and susceptor and particle size significantly contributed to the preparation of MMCs during processing. 2,56,67 The effective parameters used in this research to investigate SS316 and MMCs using MHH are given in Table 3.…”