The Microstructure and Properties of Ni-Si-La2O3 Coatings Deposited on 304 Stainless Steel by Microwave Cladding

In this investigation, microwave radiation was used alongside a combination of Ni powder, Si powder, and La2O3 (Lanthanum oxide) powder to create surface cladding on SS-304 steel. To complete the microwave cladding process, 900 W at 2.45 GHz was used for 120 s. “Response surface methodology (RSM)” was utilized to attain the optimal combination of microwave cladding process parameters. The surface hardness of the cladding samples was taken as a response. The optimal combination of microwave cladding process parameters was found to be Si (wt.%) of 19.28, a skin depth of 4.57 µm, irradiation time of 118 s, and La2O3 (wt.%) of 11 to achieve a surface hardness of 287.25 HV. Experimental surface hardness at the corresponding microwave-cladding-process parameters was found to be 279 HV. The hardness of SS-304 was improved by about 32.85% at the optimum combination of microwave cladding process parameters. The SEM and optical microscopic images showed the presence of Si, Ni, and La2O3 particles. SEM images of the “cladding layer and surface” showed the “uniform cladding layer” with “fewer dark pixels” (yielding higher homogeneity). Higher homogeneity reduced the dimensional deviation in the developed cladding surface. XRD of the cladded surface showed the presence of FeNi, Ni2Si, FeNi3, NiSi2, Ni3C, NiC, and La2O3 phases. The “wear rate and coefficient of friction” of the developed cladded surface with 69.72% Ni, 19.28% Si, and 11% La2O3 particles were found to be 0.00367 mm3/m and 0.312, respectively. “Few dark spots” were observed on the “corroded surface”. These “dark spots” displayed “some corrosion (corrosion weight loss 0.49 mg)” in a “3.5 wt.% NaCl environment”.


Introduction
Steel is a widely used material on Earth. Further, steel offers diverse properties to meet a "wide range of applications". Steel is used in various applications, such as electrical equipment (3%), domestic appliances (3%), metal products (11%), the automotive industry (12%), mechanical equipment, (15%), buildings and infrastructure (51%), and other forms of transport (5%). Steel is also used in buildings in addition to structural applications for heating ventilation and air conditioning systems, as well as items such as shelving, rails, The basic metal used in this investigation was SS-304. Standard stainless steel 304 is often used. It has a nickel content of 8% to 10.5% and a chromium content of 18% to 20%. Austenitic stainless steel describes this material. When compared to carbon steel, it is a far less conductive substance both "thermally and electrically". Nevertheless, SS-304 has a basic magnetic property that is lesser than that of steel. It resists corrosion far better than regular steel. Its malleability means it can be shaped for a broad range of purposes. However, corrosion in pits and crevices can develop in chloride-rich conditions. Above 60 • C, stress corrosion cracking might begin to appear. At temperatures of 870 • C in intermittent duty and 925 • C in continuous service, stainless steel 304 exhibits excellent oxidation resistance [22]. If corrosion resistance in water is a need, however, sustained exposure to temperatures between 425 and 860 • C is not suggested. Table 1 displays the observable properties of SS-304 up to 160 mm in diameter/thickness.

Primary Cladding Particle
Nickel in powdered form, with an "average particle size" of roughly 10 µm, is considered potential "cladding material". Nickel is a transition metal that is both hard and ductile. In order to optimize the reactive surface area, nickel powder's high chemical activity is highly beneficial [12]. However, nickel's ability to passivate steel's surface after coating it with a protective barrier also makes it resistant to surface corrosion. Because larger Ni pieces take longer to "react with air" under "ordinary circumstances", an "oxide layer" is not formed on the surface, stopping any further "corrosion". Only three other elements, "iron, cobalt, and gadolinium", are magnetic at or near "room temperature", making it one of the rarest of the rare. Above its "Curie temperature of 355 • C" (671 • F), "bulk nickel is no longer magnetic". Ni, in comparison to other transition metals, has high thermal and electrical conductivity [23]. In order to determine the purity of the particles, powder XRD was performed on Ni powder used for this investigation. Figure 1 depicts the XRD pattern of Ni powder. When X-ray powder diffraction was performed on Ni powder, almost 99.9% pure Ni was detected. However, Fe phases may also be seen in the Ni powder that was chosen to be the principal cladding particles with SS-304. the XRD pattern of Ni powder. When X-ray powder diffraction was performed on Ni powder, almost 99.9% pure Ni was detected. However, Fe phases may also be seen in the Ni powder that was chosen to be the principal cladding particles with SS-304.

Secondary Cladding Particle
Lanthanum oxide (28 μm of particle size) was used along with Ni. It is often used as a component of optical materials in some ferroelectric materials. It is also often used as feedstock for certain catalysts. La2O3 has an A-M2O3 hexagonal crystal structure at low temperatures [24]. Powder XRD of La2O3 particles used in the present study is shown in Figure 2. "Powder XRD" of "La2O3 powder" shows the "presence of La2O3 phases".

Secondary Cladding Particle
Lanthanum oxide (28 µm of particle size) was used along with Ni. It is often used as a component of optical materials in some ferroelectric materials. It is also often used as feedstock for certain catalysts. La 2 O 3 has an A-M 2 O 3 hexagonal crystal structure at low temperatures [24]. Powder XRD of La 2 O 3 particles used in the present study is shown in Figure 2. "Powder XRD" of "La 2 O 3 powder" shows the "presence of La 2 O 3 phases".

Tertiary Cladding Particle
Silicon powder (Si) was taken as a tertiary cladding particle with an average particle size of 25 μm. It is a semiconductor and a tetravalent metalloid with a blue-grey metallic luster. It is a brittle crystalline that is solid and hard. Its melting temperature is 1414 °C.

Tertiary Cladding Particle
Silicon powder (Si) was taken as a tertiary cladding particle with an average particle size of 25 µm. It is a semiconductor and a tetravalent metalloid with a blue-grey metallic luster. It is a brittle crystalline that is solid and hard. Its melting temperature is 1414 • C. Silicon powder is inactive at normal temperatures, similar to carbon, but when heated, it reacts dynamically with the halogens (iodine, bromine, chlorine, and fluorine) to form halides and with certain metals to form silicides. Figure 3 shows the "powder XRD" of "Si powder". "Powder XRD" shows the "presence of Si with a little amount of C".

Tertiary Cladding Particle
Silicon powder (Si) was taken as a tertiary cladding particle with an average particle size of 25 μm. It is a semiconductor and a tetravalent metalloid with a blue-grey metallic luster. It is a brittle crystalline that is solid and hard. Its melting temperature is 1414 °C. Silicon powder is inactive at normal temperatures, similar to carbon, but when heated, it reacts dynamically with the halogens (iodine, bromine, chlorine, and fluorine) to form halides and with certain metals to form silicides. Figure 3 shows the "powder XRD" of "Si powder". "Powder XRD" shows the "presence of Si with a little amount of C".

Development of Cladding
In this study, the "substrate (SS-304) was cleaned" with the help of "alcohol in an ultrasonic bath before deposition". The mixture of Ni, Si, and La 2 O 3 particles was preheated at 100 • C for 24 h in a "muffle furnace". "Preheating of the mixture" of Ni, Si, and La 2 O 3 particles was carried out to remove the "moisture content of the powder". The preheated powder was uniformly distributed and preplaced on the "SS-304 substrate" with an "approximately uniform thickness". However, the "interaction of microwaves" is a highly "material-dependent phenomenon". In order to overcome the problem of the "microwave being reflected by the mixture of Ni, Si, and La 2 O 3 particles", "clads" were developed using "charcoal" as the "susceptor material through microwave hybrid heating (MHH)" [25,26]. The schematic of MHH is shown in Figure 4. MHH was carried out in a "multimode microwave applicator" at 900 W using a "2.45 GHz frequency" [27,28]. In this study, the "substrate (SS-304) was cleaned" with the help of "alcohol in an ultrasonic bath before deposition". The mixture of Ni, Si, and La2O3 particles was preheated at 100 0 C for 24 h in a "muffle furnace". "Preheating of the mixture" of Ni, Si, and La2O3 particles was carried out to remove the "moisture content of the powder". The preheated powder was uniformly distributed and preplaced on the "SS-304 substrate" with an "approximately uniform thickness". However, the "interaction of microwaves" is a highly "material-dependent phenomenon". In order to overcome the problem of the "microwave being reflected by the mixture of Ni, Si, and La2O3 particles", "clads" were developed using "charcoal" as the "susceptor material through microwave hybrid heating (MHH)" [25,26]. The schematic of MHH is shown in Figure 4. MHH was carried out in a "multimode microwave applicator" at 900 W using a "2.45 GHz frequency" [27,28].

Response Surface Methodology (RSM)
RSM was used to identify the optimum combination of microwave cladding process parameters [29][30][31]. In the present study, the central composite design (CCD) in DOE was employed for experimental work [32][33][34]. The weight percent of Si, skin depth, and irradia-

Response Surface Methodology (RSM)
RSM was used to identify the optimum combination of microwave cladding process parameters [29][30][31]. In the present study, the central composite design (CCD) in DOE was employed for experimental work [32][33][34]. The weight percent of Si, skin depth, and irradiation time and La 2 O 3 (wt.%) were obvious based on the "pilot-run investigation". In the "pilot run", the arbitrary weight percent of Si was selected as 5% for the microwave cladding process with Ni and La 2 O 3 . It was found that cladding surface hardness was not improved significantly. The weight percent of Si at 15% was found to be satisfactory. However, surface hardness significantly improved by taking 20 wt.% of SiC, along with Ni and La 2 O 3 . Further beyond the Si wt.% of 25, the surface hardness of the cladding layer began to decrease. "Keeping these facts in the mind", the Si (wt.%) range was kept between 15-25%. Skin depth, irradiation time, and La 2 O 3 (wt.%) ranges were decided in the same manner. Table 2 shows the "variable process parameters" of "microwave cladding with their ranges". Table 3 shows the "design matrix table" used to conduct the experiment for surface hardness as response. Standard order (Table 3) shows the non-random sequence of the experimental runs for the fractional factorial design of the experiment in the present study. Table 2. Variable process parameters with their ranges.

Materials Testing Procedure
Microstructures of the clad samples were identified by taking an SEM image. Carbon tape was fixed on two sides of the clad samples, and the UHMWPE powder was sprinkled onto the surface. A light platinum, gold, or carbon coating was used (≈100 Å), and the clad samples were examined in an SEM chamber. A small diamond pyramid was used indenter, loaded with a small force of 100 gf for the Vickers hardness test of the clad samples [35,36]. X-ray diffraction (XRD) is the nondestructive instrument used to examine different types of substances, ranging from crystals to powders and fluids. Atoms scatter X-ray waves, first and foremost via the atoms' electrons. XRD is used to observe the percentage of crystallinity, distinguish between crystalline and amorphous materials, detect a variety of polymorphic forms, and recognize crystalline material. A corrosion test was performed in the presence of 3.5 wt. percent NaCl over 120 h. Table 4 shows the ANOVA table used to obtain the "optimal combination of microwave cladding process parameters" for "surface hardness as a response". In this case, Si (wt.%), skin depth, irradiation time,

Analysis of Variance for the Surface Hardness as a Response
(1) Table 4. ANOVA Table. "Source" "Sum of Squares" "DF" "Mean Square" "F Value" "Prob > F" The studentized residuals graph and the experimental predicted graph can be seen in Figure 5a,b, respectively. Through these graphs, it is known that the experiment that was conducted is correct through the design matrix table. The present study results show that both graphs appear to be plotted in a straight line of about 45 degrees.

Influence of "Silicon Powder Weight" Percent on Cladding Surface Hardness
The influence of "silicon powder weight percentage" on "surface hardness" can be seen in Figure 6a-c. A steady increase in surface hardness was observed when the weight percent of Si powder was taken up to the middle of the selected range. However, when the weight precept was further increased, surface hardness began to decrease. The reason for this may be that the increase in the weight percentage of Si caused some defects to arise during the "formation of the cladding layer", due to which a "decrease in surface hardness" was observed [36][37][38]. The influence of "silicon powder weight percentage" on "surface hardness" can be seen in Figure 6a-c. A steady increase in surface hardness was observed when the weight percent of Si powder was taken up to the middle of the selected range. However, when the weight precept was further increased, surface hardness began to decrease. The reason for this may be that the increase in the weight percentage of Si caused some defects to arise during the "formation of the cladding layer", due to which a "decrease in surface hardness" was observed [36][37][38].

Effect of Skin Depth of the Major Constituent on Cladding Surface Hardness
The effect of skin depth of the major constituent on surface hardness can be observed in Figure 6a,d,e. The value of surface hardness came out best when the "skin depth of the major constituent" was placed approximately between the selected process parameters (4 μm to 5 μm). Having a higher "skin depth of the major constituent" increases the chances of cracking of the substrate during the "cladding process", resulting in a decrease in the "hardness of the surface" [39][40][41]. Therefore, during the cladding process, it is kept in mind that the "skin depth of the major constituent" should neither be too high nor too low. Keeping the "skin depth of the major constituent" low, sometimes proper cladding does not occur, due to which the required increase in surface hardness is not achieved.

Effect of Skin Depth of the Major Constituent on Cladding Surface Hardness
The effect of skin depth of the major constituent on surface hardness can be observed in Figure 6a,d,e. The value of surface hardness came out best when the "skin depth of the major constituent" was placed approximately between the selected process parameters (4 µm to 5 µm). Having a higher "skin depth of the major constituent" increases the chances of cracking of the substrate during the "cladding process", resulting in a decrease in the "hardness of the surface" [39][40][41]. Therefore, during the cladding process, it is kept in mind that the "skin depth of the major constituent" should neither be too high nor too low. Keeping the "skin depth of the major constituent" low, sometimes proper cladding does not occur, due to which the required increase in surface hardness is not achieved.

Effect of Irradiation Time on Cladding Surface Hardness
The influence of irradiation time on "surface hardness" is displayed in Figure 6b,d,f. It is visible from Figure 6b,d,f that surface hardness also increases by increasing irradiation time. Microwave irradiation gives more time for cladding particles to bond with the surface, due to which the cladding surface is properly formed [42][43][44].

Effect of La 2 O 3 Powder Weight Percent on Cladding Surface Hardness
It can be seen from Figure 6c,e,f that surface hardness continuously increases when the weight percentage of La 2 O 3 increases. The reason for this is that La 2 O 3 itself is a very hard particle and when its weight percent increases, it tries to increase the hardness of the substrate very well [45][46][47]. Figure 7 shows the "ramp function graph" for the "microwave cladding input parameters". The "ramp function graph results" exhibit that if the values of Si (wt.%), skin depth of the major constituent, irradiation time, and La 2 O 3 (wt.%) are about 19.28, 4.57 µm, 118 s, and 11, respectively, then the value of cladding surface hardness should be 287.25 HV with a desirability of 1. The prominence of the "microwave cladding parameters" can be ranked based on their F ratio as exhibited in Table 5 (ANOVA table). It can be inferred that La 2 O 3 (wt.%) contributes the most, followed by Si (wt.%), irradiation time, and skin depth of the major constituent, as shown in Figure 8. The influence of irradiation time on "surface hardness" is displayed in Figure 6b,d,f. It is visible from Figure 6b,d,f that surface hardness also increases by increasing irradiation time. Microwave irradiation gives more time for cladding particles to bond with the surface, due to which the cladding surface is properly formed [42][43][44].

Effect of La2O3 Powder Weight Percent on Cladding Surface Hardness
It can be seen from Figure 6c,e,f that surface hardness continuously increases when the weight percentage of La2O3 increases. The reason for this is that La2O3 itself is a very hard particle and when its weight percent increases, it tries to increase the hardness of the substrate very well [45][46][47]. Figure 7 shows the "ramp function graph" for the "microwave cladding input parameters". The "ramp function graph results" exhibit that if the values of Si (wt.%), skin depth of the major constituent, irradiation time, and La2O3 (wt.%) are about 19.28, 4.57 μm, 118 s, and 11, respectively, then the value of cladding surface hardness should be 287.25 HV with a desirability of 1. The prominence of the "microwave cladding parameters" can be ranked based on their F ratio as exhibited in Table 5 (ANOVA table). It can be inferred that La2O3 (wt.%) contributes the most, followed by Si (wt.%), irradiation time, and skin depth of the major constituent, as shown in Figure 8.

Metallurgical and Tribo-Corrosion Behaviour at Optimum Microwave Process Parameters
Microwave cladding of SS-304 was carried out at optimum microwave cladding process parameters (Si (wt.%) of 19.28, skin depth of 4.57 μm, and irradiation time of 118 s and La2O3 (wt.%) of 11). Figure 9 shows the photograph of the "microwave clad samples" developed at "optimum microwave process parameters". Surface hardness, microstructure investigation, XRD behavior, wear behavior, and corrosion behavior of developed samples at optimum microwave process parameters (Si (wt.%) of 19.28, skin depth of 4.57 μm, irradiation time of 118 s, and La2O3 (wt.%) of 11) have been discussed as shown below.

Surface Hardness
The experimental surface hardness (average for five test samples) corresponding to the microwave cladding process parameters (Si (wt.%) of 19.28, skin depth of 4.57 μm, Irradiation time of 118 s, and La2O3 (wt.%) of 11) was found to be 279 HV. The ramp function graph shows that the theoretical value of surface hardness at the optimum microwave cladding process parameters is 287.25 HV. The results indicate that there is only a 2.96%

Metallurgical and Tribo-Corrosion Behaviour at Optimum Microwave Process Parameters
Microwave cladding of SS-304 was carried out at optimum microwave cladding process parameters (Si (wt.%) of 19.28, skin depth of 4.57 µm, and irradiation time of 118 s and La 2 O 3 (wt.%) of 11). Figure 9 shows the photograph of the "microwave clad samples" developed at "optimum microwave process parameters". Surface hardness, microstructure investigation, XRD behavior, wear behavior, and corrosion behavior of developed samples at optimum microwave process parameters (Si (wt.%) of 19.28, skin depth of 4.57 µm, irradiation time of 118 s, and La 2 O 3 (wt.%) of 11) have been discussed as shown below.

Metallurgical and Tribo-Corrosion Behaviour at Optimum Microwave Process Parameters
Microwave cladding of SS-304 was carried out at optimum microwave cladding process parameters (Si (wt.%) of 19.28, skin depth of 4.57 μm, and irradiation time of 118 s and La2O3 (wt.%) of 11). Figure 9 shows the photograph of the "microwave clad samples" developed at "optimum microwave process parameters". Surface hardness, microstructure investigation, XRD behavior, wear behavior, and corrosion behavior of developed samples at optimum microwave process parameters (Si (wt.%) of 19.28, skin depth of 4.57 μm, irradiation time of 118 s, and La2O3 (wt.%) of 11) have been discussed as shown below.

Surface Hardness
The experimental surface hardness (average for five test samples) corresponding to the microwave cladding process parameters (Si (wt.%) of 19.28, skin depth of 4.57 μm, Irradiation time of 118 s, and La2O3 (wt.%) of 11) was found to be 279 HV. The ramp function graph shows that the theoretical value of surface hardness at the optimum microwave cladding process parameters is 287.25 HV. The results indicate that there is only a 2.96%

Surface Hardness
The experimental surface hardness (average for five test samples) corresponding to the microwave cladding process parameters (Si (wt.%) of 19.28, skin depth of 4.57 µm, Irradiation time of 118 s, and La 2 O 3 (wt.%) of 11) was found to be 279 HV. The ramp function graph shows that the theoretical value of surface hardness at the optimum microwave cladding process parameters is 287.25 HV. The results indicate that there is only a 2.96% error in the experimental and mathematical model results. The average hardness of the SS-304 alloy was observed to be 210HV. The outcomes exhibit that there is about a 32.85% enhancement in the "hardness of SS-304 alloy" after the "microwave cladding of the mixture" of 69.72% Ni, 19.28% Si, and 11% La 2 O 3 particles on "SS-304 at optimum process parameters" [29][30][31]. In Figure 10a-d, the SEM image displays the "microwave clad samples" produced using a "mixture of 69.72% Ni, 19.28% Si, and 11% La 2 O 3 particles" on "SS-304" that was developed under optimal cladding parameters. The surface of the "SS-304" exhibits a uniform distribution of Ni, Si, and La 2 O 3 particles. Additionally, the presence of La 2 O 3 powder is visible on the steel surface. As demonstrated in Figure 11a-d, the use of Ni and Si powder as a coating material is effective in enhancing the surface properties of steel. The numerous "hard and carbide phases" developed after "microwave cladding", such as the Ni 3 C, NiC, and La 2 O 3 phases (Figure 12a-c), were accountable for ornamental hardness [48][49][50].      -c). SEM image of "cladding layer and cladding surface" of the "microwave clad samples" developed using a "mixture of 69.72% Ni, 19.28% Si, and 11% La2O3 particles" on "SS-304 developed at optimum cladding parameters".

XRD Behavior
XRD is a prevailing nondestructive method intended to distinguish crystalline materials. It gives information of crystal defects, strain, crystallinity, average grain size, texture, phases, and structures [57][58][59]. Figure 13 shows the XRD of the "microwave clad samples" developed using a "mixture of 69.72% Ni, 19.28% Si, and 11% La2O3 particles" on "SS-304 developed at optimum cladding parameters". XRD of cladded surface shows the presence of FeNi, Ni2Si, FeNi3, NiSi2, Ni3C, NiC, and La2O3 phases. The "formation of hard and carbide phases", such as the Ni3C, NiC, and La2O3 phases, were accountable for ornamental "hardness of SS-304 alloy" after the "cladding of the mixture of 69.72% Ni, 19.28% Si, and 11% La2O3 particles" [32][33][34]. Figure 13. XRD of the "microwave clad samples" developed using a "mixture of 69.72% Ni, 19.28% Si, and 11% La2O3 particles" on "SS-304 developed at optimum cladding parameters".  Figure 10a-d shows the SEM image of the "microwave clad samples" developed using the "mixture of 69.72% Ni, 19.28% Si, and 11% La 2 O 3 particles" on "SS-304 developed at optimum cladding parameters". "Uniform distribution of Ni, Si, and La 2 O 3 particles" can be observed on the "surface of SS-304". The presence of La 2 O 3 powder can be observed on the surface of the steel. "Ni and Si powder" itself is a "good coating material" that enhances the "surface property of steel" (Figure 11a-d). Figure 12a-c shows the "SEM image of the cladding layer and cladding surface". Figure 12a,b show the "uniform cladding layer" with "fewer dark pixels" (yielding higher homogeneity). The uniform cladding layer and cladding surface were obtained by maintaining the optimum microwave parameters (Si (wt.%) of 19.28, skin depth of 4.57 µm, and Irradiation time of 118 s, and La 2 O 3 (wt.%) of 11). By retaining the best microwave settings, a uniform cladding layer and surface were produced. The created cladding surface's dimensional deviation was minimized with increased "cladding layer and cladding surface homogeneity" [30,31]. The hardness of the cladding surface is better distributed when there is less variation in its dimensions. The wear resistance and average hardness of the produced surface are both improved by uniform hardness distribution over the cladding surface. Some fissures between the cladding layer and substrate are seen in Figure 12c. Inconsistent variations in powder and microwave settings may have led to the development of the fracture [51][52][53]. Because of fissures that formed amid the "cladding layer and the substrate", wear resistance was reduced. On the other hand, formed fissures between the cladding layer and substrate may also reduce hardness [54][55][56].

Wear Behavior
For the wear test, a "pin-on-disc machine" with a "sliding speed of 2 m/s, a sliding distance of 1000 m, and an axial load of 5 N" was used. The "wear rate and coefficient of friction" of the developed "cladded surface" with "69.72% Ni, 19.28% Si, and 11% La 2 O 3 particles" were observed to be 0.00367 mm 3 /m and 0.312, respectively, which is appropriate to be utilized anywhere. Nevertheless, the foremost purpose for "good wear resistance" is the "use of La 2 O 3 with Ni and Si powder" in the development of the "cladding surface" [60][61][62]. The development of "hard phases such as Ni 3 C, NiC, and La 2 O 3 phases" (Figure 12) on the "surface of SS-304" with "microwave cladding of the mixture of 69.72% Ni, 19.28% Si, and 11% La 2 O 3 particles" was responsible for increased "wear resistance". However, "La 2 O 3 is a hard particle" whose presence always promotes "wear resistance of the material". Wear behavior of the cladding surface of steel depends on many factors, such as cladding thickness, adhesion of cladding to the substrate, layers form after cladding, microstructure (number and size of defects, phases, and grain sizes), thermal properties of cladding and substrate, mechanical properties of cladding and substrate (fatigue strength, tensile strength, Young's modulus, and hardness), and surface roughness.

Corrosion Behavior
In the "existence of 3.5 wt. percent NaCl" over 120 h, the "corrosion test of SS-304" with "microwave cladding" of a "mixture of 69.72% Ni, 19.28% Si, and 11% La 2 O 3 particles" was conducted. "Corrosion weight loss of SS-304" with "microwave cladding" of a "mixture of 69.72% Ni, 19.28% Si, and 11% La 2 O 3 particles" was found to be 0.49 mg. Figure 14a,b shows the "SEM image of the corroded surface". "Few dark spots" may be observed on the "corroded surface". These "dark spots" indicate some "corrosion in 3.5 wt.% NaCl environment".
In the "existence of 3.5 wt. percent NaCl" over 120 h, the "corrosion test of SS-304" with "microwave cladding" of a "mixture of 69.72% Ni, 19.28% Si, and 11% La2O3 particles" was conducted. "Corrosion weight loss of SS-304" with "microwave cladding" of a "mixture of 69.72% Ni, 19.28% Si, and 11% La2O3 particles" was found to be 0.49 mg. Figure 14(a-b) shows the "SEM image of the corroded surface". "Few dark spots" may be observed on the "corroded surface". These "dark spots" indicate some "corrosion in 3.5 wt.% NaCl environment".

Conclusions
The subsequent points can be concluded from the current work: 1. The "mixture of 69.72% Ni, 19.28% Si, and 11% La2O3 particles" can be utilized on "SS-304 alloy for microwave cladding via microwave energy".

Conclusions
The subsequent points can be concluded from the current work: