Susceptor Material Research Articles

Influence of process parameters on microwave joining of the similar/dissimilar materials: A review

Conventional joining techniques like soldering, welding, and brazing are used by various fabrication industries but these processes have some limitations like more power consumption, higher processing time, and greater heat-affected zone. The need of the hour is to find alternate welding techniques that can be more environment-friendly, cost-effective, and enhance the properties of the fabricated product. Microwave welding is one such joining technique that overcome all the limitations allied with conventional joining techniques. Microwaves are generally electromagnetic waves having a wavelength range from 1 mm to 1 m and a frequency range from 0.3 to 300 GHz. Due to volumetric heating in microwave joining, the rapid joining of specimens occurred. Limited studies are available regarding the use of microwaves in joining. Various parameters that influence the microwave joining of materials are the type of interface material, exposure time, susceptor material, and power output. The present study critically reviews and summarizes the available literature on the effect of above said parameters on the microwave joining of materials. Research gaps reported in the literature have also been discussed in an attempt to create a single-valued source of knowledge that will help and guide researchers working in the area of microwave joining of materials.

Material Selection Methodology for an Induction Welding Magnetic Susceptor Based on Hysteresis Losses

Induction welding is a fusion bonding process relying on the application of an alternating magnetic field to generate heat at the joining interface. Herein, magnetic hysteresis losses heating elements, called susceptors, which are made of magnetic particles dispersed in a thermoplastic polymer, are investigated. A methodology to identify the parameters influencing the heating rate of the susceptors and to select suitable magnetic particles for their fabrication is proposed. The applied magnetic field amplitude is modeled based on the induction coil geometry and the alternating electrical current introduced to it. Then, properties of the evaluated susceptor particles are obtained through measurements of their magnetic hysteresis. A case study is presented to validate the suitability of the proposed methodology. Particles of iron (Fe), nickel (Ni), and magnetite (Fe3O4) are evaluated as susceptor materials in polypropylene (PP) and polyetheretherketone (PEEK) matrices. Heating rates are predicted using the proposed method, and samples are produced and heated by induction to experimentally verify the results. Good agreement with the predictions is obtained. Ni is the most suitable susceptor material for a PP matrix, while Fe3O4is preferable for PEEK.

Microwave Heating Capabilities of Different Susceptor Material: Experimental and Simulation Study

Microwave Heating Capabilities of Different Susceptor Material: Experimental and Simulation Study

Microwave-assisted preparation of carbon coating layer on raspberry-shaped iron oxide particles for lithium-ion battery anodes

• Raspberry-shaped iron oxide nanostructure(RSIN) shows super-paramagnetic properties. • The RSIN generates heat via microwave irradiation to carbonize polydopamine coating. • The resulting conformal carbon coating has intimate contact with the RSINs. • The capacity retention of resulting material is 87.5% after 1000 cycles at 2 A g −1 . Carbon coating is one of the important methods to suppress volumetric changes of iron oxide particle when it is used as an anode for lithium-ion batteries. Herein, we report a rapid and facile preparation of carbon coating on raspberry-shaped iron oxide nanostructure (RSIN) via microwave irradiation. The RSIN is a hollow secondary particle, which is consisted of superparamagnetic iron oxide nanoparticles. For this reason, the RSIN is used as an effective microwave initiator and generates heat to carbonize polydopamine coating on its surface. As a result, the RSIN plays a dual role as a microwave susceptor and anode material. When microwave irradiated pRSIN (MW-pRSIN) was tested as an anode material for lithium-ion batteries, a high initial reversible capacity of 893 mAh g −1 at 0.1 A g −1 is delivered. The MW-pRSIN exhibits stable capacity retention of 87.5% after 1000 cycles at 2.0 A g −1 . Furthermore, the MW-pRSIN showed a reversible capacity of 415 mAh g −1 at the first step of 8.0 A g −1 in rate performance. The outstanding electrochemical performance is attributed to an effective carbon coating, which is a result of localized heating of microwave irradiation.

Exergy transfer principles of microwavable materials under electromagnetic effects

Microwave technology is gaining an essential relevance for heating processes at an industrial level due to its improvements in energy savings and product quality. Nevertheless, the microwave system design and material selection during the applications are key points that play an essential role in the successful performance of the process, its implementation, and its operation. The proper function of the microwave highly depends on the design and a good selection of the materials. There are different kinds of materials for microwave applications such as transparent (not able to be heated), semi-transparent (low absorption of microwaves), and susceptor (materials with high capacity to absorb microwaves and transform them into thermal energy). This investigation shows the way each of these materials converts microwaves into heat. Both heat transfer and exergy transfer analyses are presented, focused on those materials with high interactions with microwaves (susceptors). The heat transfer studies demonstrated the way microwaves are transformed into heat, and the exergy analysis shows the quality of those transformations. Exergy transfer analysis of microwave heating systems sheds light on the efficiency of the energy transformation taking place during microwave processing. Consequently, by combining studies of microwavable materials with exergy transfer analysis, conclusions for new microwave designs can be reached, improving this promising technology's final performance. In this sense, this work provides an easy method to determine different materials' behavior under microwave effects.

A Study on the Dewaxing Behavior of Carbon-Black-Modified LDPE–Paraffin Wax Composites for Investment Casting Applications

Dewaxing is an intermediate step in investment casting which can determine the properties of final metallic product and is strongly dependent on the properties of pattern wax. Processing of pattern wax composites with the conventionally available heating processes is energy intensive and requires high processing time, thus resulting in the lower processing rate at larger scale. Use of microwave technology for the dewaxing study is highly attractive alternative owing to the advantage of energy-efficient processing. The processing time of pattern wax composite of paraffin wax, bitumen, polyethylene and EVA in microwaves oven as a function of susceptor has been investigated. Carbon black was used as microwave susceptor in wax composites at several weight percentages. The efficient processing and melting behavior of pattern wax composite utilizing microwave dewaxing, thanks to the creation of heat sensitive sites within the pattern wax composite by the susceptor material, were analyzed in this study. FTIR-ATR, rheometer, TGA, DSC, UTM, SEM and OM were used to study the behavior of the wax composite. With the increase in the susceptor (CB) loading from 0.15 to 0.75%, an increase in the thermal stability of 6.86% was observed as depicted by the increase in the on-set temperature of the specimens. 71.9% decrease in the melt flow time of pattern wax composite was observed with the incorporation of 1.5% of CB as compared to reference specimen which manifested an inverse relationship between susceptor loading and processing time in the presence of microwave.

Experimental study on microwave Ex-situ casting of AA 6061

Abstract Microwave processing of a metallic material melting and casting is a newly developed method. The irradiation of metallic specimen takes place inside the cavity of microwave applicator and it’s heated and melted due to microwave hybrid heating. In the present work, melting of AA 6061 established inside a commercial grade microwave oven with 1 kW power and 2.45 GHz frequency in ambient environmental condition. In this process pouring and solidification carried outside the applicator. The casket design and susceptor material properties influence on the microwave heating of specimen and hence melting of the charge. The interaction of microwave with specimen and its effect of heating and melting was observed in the present study. The developed specimen was characterized to check the cast quality. Microstructure study shows the homogenous grain structure with average grain diameter 3.25 µm. The average micro indentation hardness of the casts was found 89 HV.

Challenges in joining of metallic pipes using microwave hybrid heating

Microwave hybrid heating (MHH) is a distinct and emerging alternative joining technique used to join metallic materials compared to available conventional joining processes such as FW, TIG, MIG, etc. MHH shows significant characteristics such as selective and volumetric heating, lower processing time, eco-friendly processing against conventional joining. This paper aims to investigate the joining of 316L stainless steel pipes by incorporating micrometric size (45μm) of 316L stainless steel powder in between the faying surfaces of the candidate material. Charcoal as a susceptor material was placed at the joint zone and exposed to microwave energy at 2.45 GHz inside the domestic microwave applicator at 900 W power levels. The challenges and principles involved in joining SS 316 L pipes using MHH have been discussed and initial experimental observations have been analyzed.

Bio-inspired deposition of electrochemically exfoliated graphene layers for electrical resistance heating applications

Electrochemically exfoliated graphene (eeG) layers possess a variety of potential applications, e.g. as susceptor material for contactless induction heating in dynamic electro-magnetic fields, and as flexible and transparent electrode or resistivity heating elements. Spray coating of eeG dispersions was investigated in detail as a simple and fast method to deposit both, thin conducting layers and ring structures on polycarbonate substrates. The spray coating process was examined by systematic variation of dispersion concentration and volume applied to heated substrates. Properties of the obtained layers were characterized by UV-VIS spectroscopy, SEM and Confocal Scanning Microscopy. Electrical conductivity of eeG ring structures was measured using micro-four-point measurements. Modification of eeG with poly(dopamine) and post-thermal treatment yields in the reduction of the oxidized graphene proportion, an increase in electrical conductivity, and mechanical stabilization of the deposited thin layers. The chemical composition of modified eeG layer was analyzed via x-ray photoelectron spectroscopy pointing to the reductive behavior of poly(dopamine). Application oriented experiments demonstrate the direct electric current heating (Joule-Heating) effect of spray-coated eeG layers.

Experimental and numerical analysis of the complex permittivity of open-cell ceramic foams

Open-cell ceramic foams are promising materials in the field of microwave heating. They can be manufactured from susceptor materials and can, therefore, be used as selective heating elements. In this study, the complex permittivities of ceramic foam materials, including silicon-infiltrated silicon carbide (SiSiC), pressureless sintered silicon carbide (SSiC), silicate-bonded silicon carbide (SBSiC), and cordierite were determined. The dielectric properties of the foams were determined by the cavity perturbation technique using a TE104 WR340 waveguide resonator at 2.45 GHz. Samples were preheated in a tubular furnace, enabling temperature-dependent permittivity measurements up to 200 °C. The effective dielectric constant and effective loss factor were found to depend on the porosity and material composition of the foam. The SiSiC material had a higher effective dielectric constant than the SSiC and SBSiC ceramics. The effective dielectric constant of the foams showed a trend of gradual increase with increasing temperature. Some selected dielectric mixing relations were then applied to describe the effective permittivity of the foams and compare them with predictions from finite element simulations performed using the CST Studio Suite. The foam morphologies and simple block inclusions were used in the simulations.

MoSi2-based cylindrical susceptor for rapid high-temperature induction heating in air

Conductive susceptors are necessary for heating non-conductive materials in induction heating systems. Susceptor materials should have sufficient electrical conductivity and thermal/chemical stability under a range of environmental conditions. However, many susceptor materials oxidize in high-temperature environments, resulting in degradation and poor durability. Here, we used intermetallic MoSi2 ceramics as a susceptor material and designed a cylindrical susceptor to apply to rapid high-temperature induction heating in an oxidizing environment. MoSi2 was prepared by self-propagating high-temperature synthesis (SHS), and then used to fabricate cylindrical susceptors by slip casting. The optimal thickness of the susceptor was controlled by modelling. A MoSi2-based cylindrical susceptor with SiO2 protective layer showed higher heating rate (4.2–26.8 °C/s at 0.5–2.5 kW) than a commercial rod-type susceptor (7.7–13.6 °C/s at 1.0–2.5 kW) of the same material. In addition, our susceptor endured high temperatures below 1700 °C and severe thermal cycle (700–1600 °C, heating for 2min and cooling for 1min) during 36 cycles. In general, these results demonstrate that the MoSi2-based susceptor can be applied to a rapid induction heating furnace that can be used in air at a high temperature of 1600 °C (equal to the available temperature of a commercial graphite susceptor in H2).

Effect of Process Parameters on Hardness of AA-6063 In-Situ Microwave Casting by Using Taguchi Method

In-situ microwave casting is one of the recently developed advanced metal casting techniques in which the bulk metal and mould assembly are exposed to microwave radiations at 2.45 GHz. In in-situ microwave casting, the exposure and self-pouring is done inside the microwave. The cast quality that has been casted through the microwave casting process is directly dependent on the process parameters that are selected during the process. This paper explores the effect of process parameters on hardness of AA-6063 by using microwave hybrid heating technique. Apply Taguchi L9 orthogonal array to conduct the experimentations. Here consider three process parameters: solidification environment, susceptor material and microwave power.

The Experiment of Thickness Relationship on Ceramic Fiberboard and Silicon Carbide to Temperature Rise in Microwave Oven for Sintering Hydroxyapatite

Commercial microwave oven 800 W for sintering hydroxyapatite is being developed. The required temperature for sintering hydroxyapatite is 1200°C. A temperature 1200°C can be achieved if commercial microwave combined with susceptor and insulators material. This research is aiming to study about the effect configuration of SiC and Ceramic Fiberboard thickness to temperature rise. The results show that the presence of SiC with a thickness of the thinnest affect significantly temperature rise. The presence of CFb, as a second insulator, decrease the temperature rise and more the CFb thickness increases, more the temperature decreases.

Experimental study on effect of susceptor and separator materials on microwave melting of lead metal

Microwave melting of bulk metals is an innovative technique which works on the principle of hybrid heating. The dynamics of the process and melting time of metal are considerably influenced by the materials used in microwave processing. In the present work role of susceptor and separator materials on melting time of lead is experimented. Electromagnetic physics of the process in the view of materials which are used for tooling design and time is studied and discussed. The non-ferrous bulk metallic materials such as lead in fixed quantity was used as candidate material. Power capacity of 1100 W altered light duty commercial microwave oven, operating at 2.45 GHz is used for the study. The metallic piece was melted using susceptors-Activated charcoal and silicon carbide. The bulk pieces were preplaced inside graphite and alumina crucibles which work as a separators. The whole set up is covered with casket of refractory bricks. The temperature time characteristics of different assembly materials were examined. The result shows the considerable effect on melting temperature of lead metal with different combinations. Average temperature of above 500 °C has been observed for both crucibles with charcoal powder and below 400 °C for with silicon carbide as susceptors material with 4 min cycle time and same power level.

Microwave joining of similar/dissimilar metals and its characterizations: A review

The application of microwave radiation for the processing of different materials is increasing frequently. Initially, microwaves were used for communication purpose but, due to its thermal ability currently, it is used for sintering, cladding, casting, and joining processes. Microwave joining of the materials is an emerging field of research that previously shown some encouraging outcomes. Although microwave processing of metals is a challenging task, still researchers have developed the method of heating the metals using susceptor material. This process of heating the metals is termed as microwave hybrid heating (MHH). In this review paper, the use of microwave energy for the joining of similar/dissimilar metals is studied briefly. From the review, there are several critical parameters that are discussed for successful microwave joining. The parameters included in this study are a specimen, interface powder, susceptor material, separator sheet, and insulated bricks. The importance of the characterization is studied and explained using previous results. It is concluded that there are several metals that are not being processed using microwave energy and some of the mechanical characteristics which are not used until now.

The casting of materials using microwave energy: A review

Knowing the advantages of microwave processing on different materials, it has established a good base for the sintering process. Although it has similar advantages for other processes, still other fields are not much established for industrial use. Microwave casting is one of the emerging fields which are yet to be studied in detail. In this paper, a literature review is carried out for the microwave casting of different materials such as metals, metal matrix composites (MCC), etc. Microwave casting is processed under an apparatus that involves microwave hybrid heating (MHH) where heat is transferred to charge using susceptor material. Further depending upon the designed apparatus, microwave casting is divided as in-situ and ex-situ casting processes. If molten material is allowed to solidify inside the microwave cavity is termed as “in-situ” casting while if molten material is allowed to solidify outside the microwave cavity it is termed as “ex-situ” casting. From the review, it can be concluded that the microwave casted materials produce better properties as compared to conventional casting processes in terms of homogeneity and mechanical properties. But most of the research is reported for low melting point materials like Aluminum and their alloys. With the implementation of a new design setup, microwave casting can be used for the materials that are having a melting point above 1000 °C.

Characterization of AlN-based ceramic composites for use as millimeter-wave susceptor materials at high temperature: Dielectric properties of AlN:Mo with 0.25 vol% to 4.0 vol% Mo from 25 to 550 \xb0C

Microstructural analysis and bulk dielectric property analysis (real and imaginary permittivity at 95 GHz) were performed at temperatures ranging from 25 to 550 °C for ceramic composites comprising a hot-pressed aluminum nitride matrix (containing yttria and trace carbon as sintering additives) with molybdenum powder as a millimeter-wave radiation-absorbing additive. Loading percentages in the range of 0.25 vol% to 4.0 vol% Mo were characterized. For the temperature regime evaluated, the temperature-related changes in real and imaginary components of permittivity were found to be relatively modest compared with those driven by Mo loading. Energy-dispersive X-ray spectroscopic analysis of Mo grains and surrounding regions showed the presence of a mixed-phase layer, containing Mo2C, at the AlN–Mo interface. The Mo2C-containing mixed-phase layer, typically a few micrometers thick, surrounded the Mo grains. Further characterization of this mixed-phase layer is required to determine its contribution to the dielectric properties of the composite.

A study on microwave susceptor material for hybrid heating

Efficient use of available resources at controlled and potential manner required a systematic approach for the technological advancement and creating product solutions. The proper choice of susceptor material for the desired heating rate is a prime concern for the effective utilization of microwave radiation and lower down the energy requirement. The present paper presents a comparative analysis of three different susceptor materials namely graphite boat, charcoal, and silicon carbide for the use in microwave hybrid heating (MHH). These susceptor materials are tested experimentally with 900W and 2.45GHz electromagnetic frequency to highlight the key role of a hybrid mode during microwave processing. The results claimed that the maximum temperature achieved in case of graphite boat is 350 0C with 70 minutes of exposure. However, in the case of charcoal and silicon carbide, the maximum achieved temperature is 410 0C and 255 0C respectively at duration of 10 minutes.

Characterization of AlN-based Ceramic Composites for Use as Millimeter Wave Susceptor Materials at High Temperature: High Temperature Thermal Properties of AlN:Mo with 0.25% to 4.0% Mo by Volume

In order to begin to evaluate and model the suitability of high temperature ceramic composites, such as AlN:Mo, as susceptor materials for power beaming applications, the electromagnetic, thermal, and mechanical properties of the material must be known at elevated temperatures. Work reported here focuses on the development of thermal property datasets for AlN:Mo composites ranging from 0.25% to 4.0% Mo by volume. To calculate thermal conductivity of the AlN:Mo composite series, specific heat capacity, thermal diffusivity, and density data were acquired. The calculated specific heat capacity, Cp, of the set of AlN:Mo composites was, on average, found to be approximately 803 J/kgK at 100 °C and to increase to approximately 1133 J/kgK at 1000 °C, with all values to be within +/- 32 J/kgK of the average at a given temperature. These calculated specific heat capacity values matched values derived from DSC measurements to within the expected error of the measurements. Measured thermal diffusivity, α, of the set of AlN:Mo composites was, on average, found to be approximately 3.93 × 10-1 cm2/s at 100 °C and to increase to approximately 9.80 × 10-2 cm2/s at 1000 °C, with all values within +/- 1.84 × 10-2 cm2/s of the average at a given temperature. Thermal conductivity, k, for the set of AlN:Mo composites was found to be approximately 108 W/mK at 100 °C and to decrease to approximately 38 W/mK at 1000 °C, with all values within +/- 5.3 W/mK of the average at a given temperature. Data trends show that increasing Mo content correlates to lower values of of Cp, α, and k at a given temperature.

Effect of Different Amount of Silicon Carbide on SAC Solder-Cu Joint Performance by Using Microwave Hybrid Heating Method

Microwave hybrid heating (MHH) has been recognized for the soldering process especially with lead-free solder alloy. This study seeks to investigate the effect of the different amount of susceptor on the Sn-3.0Ag-0.5Cu-Copper (SAC305-Cu) joint performance by using the MHH method. The susceptor material that was used to facilitate microwave heating in this study was Silicone Carbide (SiC). Different amount of SiC was used to compare its effect on the intermetallic compound (IMC) formed and shear strength at the solder joint. Domestic microwave with operating frequency 2.45GHz and 800W was used to join the solder and Cu substrate for 5, 6 and 7 minutes. Characterization of the samples was carried out using an optical microscope, image analyzer, and lap shear test. The microstructural study showed that scallop type structure of Cu6Sn5 was found at the SAC305/Cu interface after soldering with MHH technique. Thinnest Cu6Sn5 IMC (14.909 mm) were obtained by soldering with 6 g of SiC for 6 minutes while highest shear strength was observed when 4 g of SiC was used for soldering for 7 minutes (26.71 MPa).