Through suitable modification of the physicochemical properties of zeolite A, it can be used in different and diverge applications. These modifications are possible with the incorporation of specific cation, which causes changes in their various properties following pore size and geometry. The changes improve their activity and enable them to act as a special additive with the replacement of native cations to some exotic metal ions. Exotic metal, silver for example, can provide broad spectrum antibacterial activity at very low concentrations, satisfactory safety in usages and inherent stability through the controlled release. Silver can be incorporated within zeolite A through ion exchange process followed by the incorporation of this zeolite into the resin system for the application of antimicrobial powder coating surfaces. Powder coated surface are normally required to be cured at 200 o C for 10 minutes. During this curing process ionic silver (Ag + ) is reduced to metallic silver (Ag o ), which makes the surface inactive against microorganisms. To overcome this problem some researchers incorporated copper into the additive with silver by ion exchange process and found to be effective . The redox potential of these cations plays the main role to keep the silver ions in their original state.
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protection (Misev 1991). In summary, the popular “four E’s” were introduced: ecology, economy, energy and excellence of finish (Bosschi 1986). Based on these advantages, powder coating has already been applied to coat appliances, furniture, architectural and building materials and the underhood parts and primer coats in the automotive industry. In these markets, powder coating has fully or partially replaced traditional liquid coating. Currently, powder coatings account for roughly 10% of the industrial paint market, and have experienced an annual growth rate between 10 and 13% over the last 20 years (Richart 2001). The most prominent uses of powder coating are lawn and garden equipment, architectural uses and general metal finishing (Richart 2001). The automobile industry is also an increasing market for powder coating, even though most consumption is limited mainly to underhood components. For instance, clear coats made by powder coating have been successfully applied in BMW’s 5 and 7 series vehicles (Biller 2006). Another potential market of powder coating lies in pharmacy industries, like the coatings on pharmaceutical dosage to control drug release rate (Sastry et al. 2000; Daniher and Zhu 2008).
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Shah et al. (2006) deals with comparison of electrostatic fine powder coating and coarse powder coating by numerical simulations. The air flow rate is one of the variable parameters that can affect on the First Pass Transfer Efficiency (FPTE). Airflow by means of the aerodynamic force plays a very important role in transporting particles from spray gun to the region near the coated part. Once the particles are in the region near the coated part, the electrostatic force will plays key role in depositing the particles onto the coating target surface. From the experiment, the FPTE initially increases and then decreases when the airflow rate increases. The airflow rate initially helps the particles to reach the coating part to increase the transfer efficiency. But further increase in the airflow rate eventually decreases the FPTE because the increased turbulence makes the particles more dispersed near the region of the coated part and missed the coating part. It leading to reduced FPTE for a definite coating part. The transporting air must be strong enough to direct the particles in the direction of the spray, but the particles will lose their momentum when reaching near the target surface where the electrostatic force should be dominant for higher deposition rate.
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This paper proposes a theoretical design of a detailed assembly to automate the powder coating process. Most hospital furniture manufacturing industries employ workers to powder coat various parts of the furniture. Manual operations require a lot of time, money, manpower, apart from health hazards on the side of worker. In order to enhance existing process so as to improve productivity and save working capital, it becomes crucial to automate the mechanical operations using mechanism to move the mechanical tool and control the motion using controllers. This paper gives emphasis on the design of the mechanism for the powder coating which incorporates two lead screws for horizontal and vertical motion of powder gun. In this research, design and modelling is obtained using Creo for lead screws.
7) Shah et al. (2006) this paper carried out on the study of the coarse powder and air flow. It about the particle flow behavior in the powder coating booth & its coating quality under certain conditions. The parameters powder charging, powder flowing space are main variable in which the charged powder accelerated from gun to the substrate under the effect of aerodynamic, electrostatic and gravity forces and powder deposition to the work pieces. The important parameters that affect the powder travelling are air flow rate, powder spray rate and applied voltage.
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In order to understand the mechanism of EMI shielding, the X-ray diﬀraction (XRD) of the coatings and the electrical conductivity of the powders were measured. Figure 6 shows XRDs of the Sn-20Al-2L coating and Sn-40Al-2L coating. The results show that the microstructure of the Sn-20Al-2L coating is similar to that of the Sn-40Al-2L. The solid solution limit of Al was low in Sn matrix, and the Sn-Al precipitated phase not only aﬀected the brittleness of the powders, but also induced a variation in an electric conductivity. These are 2 reasons why the Al content was closely related to the mechanism of EMI shielding.
Resins or binders are the main component of a coating formulation. The curing properties, adhesion to the substrate and mechanical characters are related to them. For magnet or transformer applications, the coating for electrical insulation should have properties including: high dielectric strength to avoid electrical shorts; uniformity, as measured by a minimum number of faults or defects; good mechanical strength (toughness) and/or structural integrity (hardness); flexibility to permit working of the coated wire; and good heat resistance to prevent decomposition and/or melting from exposure to elevated temperatures and temperature cycling during, for example, ballast production and/or end use applications (current flow). Good mechanical strength is especially important in connection with magnet wires that are wound repeatedly around a mandrel. It is also important that such wires be non-tacky and smooth and that they possess good slip qualities to improve handling during winding operations .
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Methods to overcome the Faraday Cage effect for corona charge spraying is always desired. In industrial applications, the Faraday Cage effect can largely influences the production rate since touch-ups by the extra manual spraying processes are always required. It does not just increase the cost and time but it also causes non-uniform thicknesses of the coatings. Many efforts have been made to reduce the Faraday Cage effect for corona charge spraying. One typical example is the development of the internal charging corona spray gun [8-9]. The internal corona spray gun has the corona electrode enclosed by a grounded cylinder. When coating process starts, the generated electrostatic field converges to the grounded cylinder instead of the coating surface; therefore, the Faraday Cage effect could be reduced. However, large amount of powder particles accumulate on the cylinder surface during spraying. As a result, a reverse discharge, which was caused by severe back ionization due to the over accumulation of the charged particles, could easily occur. It is dangerous since spark from the reverse discharge can ignite the powder coating. On the other hand, the internal charging design reduces the intensity of the ionization since the gun electrode is enclosed inside a limited space and the free electrons always tended to attach to the grounded cylinder surface. Therefore, the charging of the particle is poor. So far, there has been no success with the design of the internal corona spray gun.
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The friction tests of the boro-nitrided coating were carried out using a CSM ball-on-disk tribometer in an ambient environment (20-25 °C, 45 – 60% RH). Dry sliding against AISI 52100 steel balls (6 mm in diameter) was performed. The applied normal load was selected to be 10 N, creating a maximum Hertzian stress of 1.5 GPa. This configuration and the applied pressure was intended to emulate the stress conditions for various automotive applications such as pump shafts  or tubing systems in oil production . The frictional plot against sliding distance could be recorded continuously at a sliding velocity of 0.02 m s -1 .
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Electrical Discharge Coating (EDC) as known as Electrical Discharge Alloying (EDA). It is the new trend of technology which used the Electrical Discharge Machine Die Sinker to deposit a layer of coating on the workpiece surface (Funatani et al. , 2004). Based on the previous study, this technology still in a research stage and not yet being widely used in industry. EDC or EDA is a new process that can deposit the material on the surface of workpiece in a short period with a high current electrical pulse and the present of dielectric fluid (Funatani et al. , 2004). Figure 2.5 shows the basic schematic diagram of an electrical discharge coating process.
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When HAp is deposited onto Ti-6AI-4V, a chemical reaction with titanium dioxide (the surface layer of the titanium alloy) at 1000°C forms CaTiOa and tricalciumphosphate. 18 The CaTiOs, a compound formed from the substrate and the Hap coating, acts as a bond layer. The formation of an interfacial compound is not unique to the plasmaspraying process since this also occurs with electrophoretic coatings.46 Thus, the adhesion of HAp to Ti alloys is much stronger (- 60 MPa) than bonding mechanisms, which rely on only mechanical interlocking. It is important to point out that the plasma spraying process can be carried out under either ambient or low pressure condition 14 .
characteristic in the powder (powder A: ﬁne and inhomoge- neous grains, powder B: coarse and homogeneous grains) on the coating properties, hardness, electrical and thermal conductivities of super-sonic ﬂow deposited Cu coating layer. The super-sonic ﬂow deposited coating layer using small and homogeneous distributed particles appears to have a low surface roughness and low porosity content. Small powder particles can have a higher impact velocity in the spraying process and thus result in dense and less fault microstructure by strong plastic deformation of a particle. In addition, the porosity content of the super-sonic ﬂow deposited coating continuously decreases with annealing heat treatment. Microstructure of the A coating layer was found to consist of relatively irregular and ﬁne grains compared with those in the B coating layer. It could be reasonably related with the extraordinary increase of hard- ness in the A coating layer. It was also found that an annealing heat treatment led to the evident recovery, recrystallization, and grain growth of the deformed grains. The variation of hardness of super-sonic ﬂow deposited coating layer through annealing heat treatment could be consistent with that of the microstructure. The abrupt decrease of hardness appears exactly at the starting temper- ature of recrystallization. Electrical and thermal conductiv- ities of the B coating layer represented higher value than that of the A coating layer in all of the as-sprayed and annealed conditions. Furthermore, conductivities of the B coating layer are more signiﬁcantly improved by an annealing heat treatment than those of A coating layer. It can be explained by considering the low porosity content of the B coating layer, mainly caused by the characteristic of the small and homogeneously distributed B powder particle. The annealed B coating layer represented similar electrical conductivity and slightly lower thermal conductivity than those of Cu bulk material, implying outstanding results considering those conductivities of other thermal spraying methods.
A small chamber is used to create supersonic velocity of exhaust. The focused exhaust stream receives the powder material at a velocity that the resultant impact forges adequate bonding. In fact, the impact from the kinetic energy is so great that most of the porosity is eliminated. As such, the less porous coating provides the best wear resistance and densest coatings available. The HVOF thermal spray process uses the combustion gases such as propane, propylene hydrogen or a liquid fuel such as a kerosene fuel and oxygen.,,,
The FTIR spectra for curcumin and its formulations were showed in Figure 2-5. The prominent spectrum of curcumin are as follows; 3512, 1627, 1508, 1429, 1281, 1206, 1153, 1026, 963, 856 and 814 cm -1 . Generally, the stretching region of hydroxyl group, O-H was showed at the band range of 3200- 3600 cm -1 . The band at 3510 cm -1 indicates the presence of hydroxyl group in the curcumin; sharp peak was noticed for carbonyl in curcumin. The band of alkanes (C-H) is shown at 1350-1512 cm -1 . Stretching bands at 1000-1260 cm -1 indicated the presence of ether group (C-O). The results obtained from FTIR, revealed presence of all characteristics peaks of curcumin in formulations which confirm no drug excipient interactions. Curcumin constructive peak points out that Curcumin has almost entirely converted from crystalline to the amorphous state. This transition is due to Curcumin solubilization in the liquid vehicle that was absorbed into the carrier such as avicel and adsorbed on to the coating material such as aerosil.
The trait T 0, without addition of feldspar powder, showed the lowest value of tensile strength. According to the ANOVA statistical analysis, the T 20 trait was the one that obtained the highest variance showing that this substitution percentage presents a significant increase in the tensile strength of the mortar coating compared to the reference trace T 0. The flexural tensile strength test was performed after the diametral compression tensile test. Three prismatic specimens aged 28 days were used. The results of this assay are described in Figure 8. The test of Tensile Strength in Flexion showed that the higher the percentage of substitution, the higher the Tensile Strength Limit. The T 30 trait obtained the highest mean result being approximately 147% greater than the reference trait T 0, followed by the T 20 trace that presented a value approximately 144% higher. Again the trait T 0 obtained the lowest result. According to ANOVA statistical analysis the trait T 30 was the trait that presented a greater statistical variance showing that this percentage of substitution is the most significant for the increase of tensile strength. Comparing the results of the T 20 trace with the T 30 one can say no to a statistically significant variance between the two results. Comparing the results obtained in the test with the results of Pedro (2016) it was observed that there was a significant increase in tensile strength in flexion with the use of additive to fix the water / cement factor (a/c), with the trace T 30 obtained the most significant increase, about 65%, and the T 20 trait obtained an increase of about 17% improving the traction combat in the mortar coating. For the test of determination of the Resistance to Axial Compression were used the test specimen halves of the tensile test in flexion respecting the age of 28 days. Figure 9 shows the results of this assay.
The coating material used in this coating process is Aluminium which has following properties,Aluminium is a soft, lightweight metal normally with a dull gray appearance caused by a thin layer of oxidation that forms quickly when the metal is exposed to air. Aluminium oxide has a higher melting point than pure aluminium. Aluminium is nontoxic (as the metal), nonmagnetic, and non sparking. It has a tensile strength of about 49MPa in a pure state and 400MPa as an alloy.
lower half hilt overlap to fasten the pin as shown in Figure 3b. Control the tractor to pull the latch from the latch disc. When the latch is pulled from the disc and the coating is not destroyed on the sample surface, the result is the traction that reflects the adhesion strength of the coating with metal substrate.
Copper base alloys such as bronze, lead bronze and phosphor bronze have excellent sliding properties. These materials contain small amounts of lead because of the excellent self-lubricating properties of the lead. However, the standard amount of lead in drinking water was limited to less than 0.01 mg/L by the WHO in 1992, because the intake of lead is harmful to the human body. 1) Furthermore, in order to obtain the certiﬁcation of ISO14000 series, enterprise must consider environmental safety manufacturing. Due to these factors, a lead-free material with the same sliding properties as lead was produced. This material consisted of a Cu alloy spray coating in which the solid lubricant was dispersed in the composite material. Generally, graphite is commonly used as a solid lubricant. However, the composite thermal spraying of graphite powder and Cu alloy powder is diﬃcult because the density of the graphite is much smaller than that of the Cu alloy. In this study, calcium ﬂuoride (CaF 2 ) was
and anode current efficiency(%) (calculated by Eqs. (1)–(3)) of zinc sacrificial anodes in the self- discharge test were summarized in Table1. The OCP of all the anode samples were stable enough, between - 0.9000 V with - 0.9900 V. The results showed that Ocp(A)<Ocp(B)<Ocp(C). The OCP became positive when the surface of anode was coated with agar, also coated with powder of barnacles and oysters. It could be concluded that the attached macro-foulings inhibited the transportation of corrosive media (special Cl - and O 2 ), which causing protective effect in early stage, so the average
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The formulation ingredients containing drug, porous carrier, effervescent agent and matrix carrier for a batch 300 tablets were weighed accurately and passed through # 100 mesh sieve and the powder was uniformly blended in a cube mixer. The powder blends of CC1 to CC4 and CT1 to CT3 were wet granulated with water and starch paste (15% w/w) as binder to produce wet mass. The wet mass was passed through mesh # 16, dried in an oven at 40°C for 4 - 5 h, and again passed through mesh # 20. Later, talc and magnesium stearate as required were incorporated and blended. Later for formulations T1 to T3 the powder blends of ingredients were wet granulated with (1.5% w/w) each of guar gum, xanthan gum and HPMC K4M as binder in water to produce wet mass. The wet mass of respective coat formulations was then passed through mesh # 14, dried in an oven at 40 ° C /30 % RH for 4 h. Later dried coat granules were passed through mesh # 16. Later, talc and magnesium stearate were incorporated as glidant, lubricant and blended thoroughly. The granules were studied for their rheological parameters and used for compression coating over esomeprazole core tablets. [9, 10]
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