Carbon-containing-titania coated stainless steel prepared by high voltage powder spray coating and its adhesion phenomena

2020 ◽  
Vol 147 ◽  
pp. 105782
Author(s):  
Farah Syuhada Abdul Halim ◽  
Sheela Chandren ◽  
Hadi Nur
Keyword(s):  
Stainless Steel ◽  
High Voltage ◽  
Spray Coating

scholarly journals High voltage powder spray coating as a new method for the preparation of carbon-titania coated stainless steel

2017 ◽  
Vol 13 (4) ◽  
pp. 812-816
Author(s):  
Farah Syuhada Abdul Halim ◽  
Sheela Chandren ◽  
Madzlan Aziz ◽  
Leaw Wai Loon ◽  
Hadi Nur
Keyword(s):  
Stainless Steel ◽  
High Voltage ◽  
Simple Technique ◽  
Spray Coating ◽  
Nitrogen Atmosphere ◽  
Adhesion Test ◽  
Tio2 Sample ◽  
Polymer Powder ◽  
No Weight Loss ◽  
Peel Adhesion

High voltage powder spray coating (HVPSC) is one of the methods used for coating substrate with polymer powder in industries. This study utilizes HVPSC as a new deposition method of carbon-based powdered materials on stainless steel. Carbon-titania (C/TiO2) coated stainless steel was successfully prepared from the mixture of epoxide and titania powder, sprayed onto stainless steel plate using HVPSC, followed by pyrolysis at 300 °C under nitrogen atmosphere. The functional group of C/TiO2 was confirmed by Fourier transform infrared (FTIR) spectroscopy, where the FTIR spectrum showed the presence of C─H sp3, C═O, C─O, and Ti─O peaks. The morphology of the C/TiO2 sample studied using field emission scanning electron microscopy (FESEM) clearly shows that the particles of TiO2 were coated with carbon on their surface.  The coating performance was evaluated through the abrasion test and showed no weight loss. Adhesion of C/TiO2 coating was also tested in the peel adhesion test and the result showed that the attachment of C/TiO2 on the stainless steel is very strong. It has been proven that the HVPSC method is not only a simple technique to coat materials but also a very durable one

Hybrid elevated-temperature, low/high-voltage plasma immersion ion implantation of AISI304 stainless steel

2001 ◽  
Vol 135 (2-3) ◽  
pp. 178-183 ◽  
Author(s):  
X.B. Tian ◽  
Y.X. Leng ◽  
T.K. Kwok ◽  
L.P. Wang ◽  
B.Y. Tang ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Elevated Temperature ◽  
Ion Implantation ◽  
High Voltage ◽  
Plasma Immersion Ion Implantation

Cyclone Maintenance Improvement via Special Refractory Anchor Pin Studs

2004 ◽  
Author(s):  
Stephen R. Swartz
Keyword(s):  
Stainless Steel ◽  
High Temperature ◽  
Thermal Cycling ◽  
Thermal Spray ◽  
Effective Means ◽  
Protective Layer ◽  
Spray Coating ◽  
Cycle Performance ◽  
Alloy 625 ◽  
430 Stainless Steel

Since the inception of the cyclone style boiler, industry has become accustomed to performing routine maintenance during every scheduled shutdown occurring 12 months to 18 months between cycles. These maintenance cycles are influenced by service factor, loading and the type design. The same problems exist in both the standard and super critical cyclones; severe deterioration of refractory and the anchoring pin studs. This paper focuses on one type of refractory failure mechanism caused by the anchoring pin studs. Most operators have found that the most effective means of applying refractory in this type situation is to “ram” the refractory in and around the anchoring pin studs thus creating a dense lining with maximum integrity. Coupled with proper application of anchoring pin studs and a special designed coating, typical volumetric expansion of the pin studs from corrosion attack and oxidation is eliminated thus extending the life of the refractory. This mechanism is discussed along with the results of the coating performance as it relates to extreme heat oxidation and thermal cycling in laboratory tests. A protective coating was developed using a nano-cored thermal spray wire technology that produces a uniform, adherent protective layer against high temperature corrosion and oxidation. The coating yields similar thermal conductivity as a bare stud thus experiencing excellent thermal cycle performance. This specially designed thermal spray coating is applied to standard 430 stainless steel pin studs thus providing the necessary barrier against aggressive high temperature environments while maintaining excellent heat conductivity. The coating has a high amount of tungsten (40+%) in a nickel matrix with greatly reduced oxides at the substrate and throughout the coating. With these attributes for the anchoring pin studs in mind, a newly designed stud was evaluated in heat oxidation tests up to 2000°F and thermal cycling test and compared to 430 stainless steel, chromized and Alloy 625. The new stud out-performed all others even in the as-welded condition. Further corrosion testing in ferric chloride (ASTM G48) showed them to be superior to Alloy 72 and Alloy 625 in the thermal spray and welded condition. Proper welding equipment and welding techniques are also discussed since weld continuity impacts overall performance of anchoring pin studs with refractory linings. A major test site will be examined in the spring of 2004 for it’s full effectiveness in service and will be documented in order that all data retrieved would be available to the entire industry.

scholarly journals Electrospray characteristics of aqueous KCl solutions with various electrical conductivities

2018 ◽  
Author(s):  
Sahand Faraji ◽  
Behnam Sadri ◽  
Babak Vajdi Hokmabad ◽  
Esmaeil Esmaeilzadeh ◽  
Navid Jadidoleslam
Keyword(s):  
Electrical Conductivity ◽  
Experimental Study ◽  
Stainless Steel ◽  
High Voltage ◽  
Room Temperature ◽  
High Voltage Electrode ◽  
Flow Rates ◽  
Conductivity Variation ◽  
Electrical Conductivities ◽  
Stainless Steel Ring

In the present experimental study, the effects of electrical conductivity on electrospraying procedure are investigated.A metallic nozzle with 600 m ID as high voltage electrode and a stainless steel ring as a groundelectrode were employed. Experiments were carried out in still room temperature. Four different aqueous KClsolutions were sprayed in various high voltages and flow rates. Results confirm that spraying modes changeswith conductivity variation. For forming a cone shape, emerging from the nozzle, required applied electric fielddecreases with conductivity increasing. Results also revealed that conductivity of dispersed solution acts a mainrole on forming and elongation of the cones in electrospraying procedure. The size and velocity of emanateddroplets are also investigated in order to gaining some insight to the electrospraying phenomenon.

Tantalum Based High-Pressure Cold Spray Coatings on Stainless Steel Substrate

2019 ◽  
Vol 813 ◽  
pp. 429-434
Author(s):  
Jagannadh V.S.N. Sripada ◽  
Megil F. Gallant ◽  
Gobinda C. Saha ◽  
Reeti Singh ◽  
Jan Kondas
Keyword(s):  
High Pressure ◽  
Stainless Steel ◽  
Cold Spray ◽  
Stainless Steel Substrate ◽  
Steel Substrate ◽  
Transition Element ◽  
Spray Coating ◽  
Deposition Efficiency ◽  
High Heat ◽  
Inlet Temperature

Tantalum as a transition element possesses good corrosion resistant properties, along with ductility and hardness. It is also one of the best heat-resistant material (melting point 2996°C) and is known for its high heat and electrical conductivity. In this research, Tantalum is deposited on stainless steel substrate using high-pressure cold spray (HPCS) method. Cold spray coating technology enables the deposition of powder feedstock without melting. Feedstock particles are propelled through a nozzle at supersonic velocities and they deform plastically on impact, resulting in good bonding strength to the substrate. The low temperature and solid-state deposition associated with cold spray allows refractory materials such as Ta, Mo, and W to be deposited without high temperature requirements. The objective of this work is to achieve a dense and nonporous coating microstructure with a high deposition efficiency. The hardness of as-received tantalum particles is found to be 279 HV0.3 and the microstructure is very dense. Tensile testing carried on the sample coated at a stagnation gas pressure of 50 bar and gas inlet temperature of 900°C exhibited an ultimate tensile strength of 442 MPa and adhesion strength of 77 MPa. Further mechanical properties of the coating in terms of hardness is carried out by nanoindentation. These results will be correlated with microstructural imaging and elemental analysis including morphology and composition using scanning electron microscopy and X-ray diffraction techniques.

Radiation Damage Study of Type 304 Austenitic Stainless Steel by High Voltage Electron Microscopy

1972 ◽  
Vol 30 ◽  
pp. 678-679 ◽  
Author(s):  
Gopal Das ◽  
Terence E. Mitchell
Keyword(s):  
Electron Microscopy ◽  
Stainless Steel ◽  
High Voltage ◽  
304 Stainless Steel ◽  
Irradiation Damage ◽  
Widespread Application ◽  
High Voltage Electron Microscopy ◽  
Voltage Electron ◽  
High Voltage Electron ◽  
Type 304

In recent years high voltage electron microscopy has found widespread application to simulate the kind of damage produced by neutrons in potential nuclear reactor materials and to study ‘in-situ’ the nucleation and growth of defect clusters, such as dislocation loops and voids.In this investigation AISI Type 304 stainless steel has been used as a prototype to study electron irradiation damage as a function of accelerating voltage, irradiation time and temperature. A preliminary result on such studies will be reported here. 0.4 mm thick discs were cut from as-received 3 mm rods. They were sand-ground to 0.2 mm and most of them were encapsulated in a quartz tube under a vacuum of 10−5 torr and subsequently annealed at 1100°C for 7 hours. Electron transparent foils were made from annealed and as-received discs by a two-step process of jet dimpling and electropolishing.

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